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Zenta
01-22-2008, 06:23 AM
Hi!

For almost 9 months ago I started with a hexapod project called Phoenix. Each leg has 3 DOF. Almost all parts are custom made. The coxa design was inspired by micromagicsystems (http://www.micromagicsystems.com/) hexapod v4b.



Hardware:

12 x Hitec HS645 MG (http://www.hitecrcd.com/servos/show?name=HS-645MG) servo for the femur and tibia
6 x Hitec HS475 HB (http://www.hitecrcd.com/servos/show?name=HS-475HB) servo for the coxa (what's coxa, femur and tibia? take a look at this picture (http://en.wikipedia.org/wiki/Image:Scheme_ant_worker_anatomy-en.svg))
SSC-32 servo controller
BlueSMIRF (http://www.sparkfun.com/commerce/product_info.php?products_id=582) from SparkFun bluetooth interface
Software:

Visual Sequencer (SEQ (http://www.lynxmotion.com/Product.aspx?productID=443&CategoryID=15)) from Lynxmotion
Phoenix Excel Program (PEP), EDIT: see attached .rar file, also remember to activate macros when opening it in MS Excel
Here is a picture of Phoenix:

http://i214.photobucket.com/albums/cc6/ZentaOlbaid/Phoenix02.jpg

And some more:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenix04_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=105&c=)

http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenix03_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=104&c=)

At first I made Phoenix with an inline body, here is a picture of her old inline body together with the new ovale body and some other tibia parts I tried:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenix01_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=102&c=)

PEP is a MS Excel spreadsheet I've made, its a tool for making walk and movement sequences. The sequences are imported and export between PEP and SEQ. The PEP sheet take care of all IK (inverse kinematics (http://en.wikipedia.org/wiki/Inverse_kinematics)) calculations for all legs, body movements and rotation along all axis. It's also possible to define centrepoint of rotation and make different walking gaits.

A screen capture of the main sheet called Body&Coxa:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/body_coxa_hoved_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=107&c=3&userid=1535)

This the sheet where all sequences and steps are saved:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/ind_sekvenser_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=108&c=3&userid=1535)

With PEP I'm able to create some very unique moves, here is a youtube movie:


http://www.youtube.com/watch?v=IqWKGh4XLbk
PEP is made freeware, you can download it on my project page (http://www.lynxmotion.com/images/html/proj098.htm) at Lynxmotion.

Another movie while she (yes Phoenix is a she, lol :wink:) is playing with a box:


http://www.youtube.com/watch?v=a_QUk7pL5lw

And finaly when Phoenix is running all sequences:


http://www.youtube.com/watch?v=SdR0q-suw0c

Here is a movie while she write a message:


http://www.youtube.com/watch?v=P0pJ1RALDZ0

Update: phoenix and the box part II:


http://www.youtube.com/watch?v=NUMGpDTm59w

For the time I'm also working with an octopod robot called Oxyopus, I'll post more information about him later.
Oxyopus:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/oxyopus08_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=101&c=member&imageuser=1535)

-Zenta

DresnerRobotics
01-22-2008, 10:17 AM
Wooohoooo Zenta!

I cannot tell you how much I love this hexapod, by far the most advanced movements I have ever seen, and to think it's I.K. calculations were 100% custom built using Excel. That blows my mind man. You should post up a pic of what your PEP screen looks like, I didn't even know Excel could be used that way. I see you uploaded a lot more pics to your gallery too.

Can't wait to see more on your Oxyopus, and the gait you're talking about is going to be amazing.

Good luck!

Zenta
01-22-2008, 02:21 PM
You should post up a pic of what your PEP screen looks like, I didn't even know Excel could be used that way. I see you uploaded a lot more pics to your gallery too.

Hi Tyberius!
Thanks, I've edited the main post with some more pics and two screenshoots of PEP.

-Zenta

Alex
01-22-2008, 03:28 PM
Incredible work Zenta! You built all of this yourself? What did you use for designing and cutting the bracket system? Are those like aluminum t-blocks (no, I'm not a mechanical engineer:p) at the joints on the body? Nice work on the cable management too! How sturdy are those single brackets connecting the legs from the shoulders? Sorry I'm just loving this spider and have a ton of questions!

I would love to see a video of Phoenix just walking around. That is just sooo life-like. I had chills when I saw Phoenix move!

Definitely get your Oxyopus project up when you get a chance. Did you build that yourself too? You might want to wait till the next contest round for an official project entry (it'll start March 1st), except of course if you have other projects to enter!

EDIT: Almost forgot! I got you entered in the contest:)

Zenta
01-22-2008, 04:20 PM
Incredible work Zentra! You built all of this yourself? What did you use for designing and cutting the bracket system? Are those like aluminum t-blocks (no, I'm not a mechanical engineer:p) at the joints on the body? Nice work on the cable management too! How sturdy are those single brackets connecting the legs from the shoulders? Sorry I'm just loving this spider and have a ton of questions!
Hi Alex!
Thanks, Yes I've built them both all myself. The coxa brackets are milled of aluminium with a XYZ drilling machine:
http://forums.trossenrobotics.com/gallery/files/1/5/3/5/xyzdrillingmachine_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=109&c=3)
No "T-blocks", all custom made ;)
Those single brackets (femur and tibia joint) are a bit flexing and they do stress the joint, not healthy for the servo :rolleyes: (especially for the femur servo) I think. But that's the price for a more flexible and agile hexapod :p lol.



I would love to see a video of Phoenix just walking around. That is just sooo life-like. I had chills when I saw Phoenix move!
Sorry, I don't have any movies of only walking. Maybe later;)


Definitely get your Oxyopus project up when you get a chance. Did you build that yourself too? You might want to wait till the next contest round for an official project entry (it'll start March 1st), except of course if you have other projects to enter!

EDIT: Almost forgot! I got you entered in the contest:)
So, you suggest I should post Oxyopus for the next contest? That's OK for me. I'm still working with it and I don't have any other project to enter right now.

-Zenta (not Zentra :wink:)

Alex
01-23-2008, 09:45 AM
The coxa brackets are milled of aluminium with a XYZ drilling machineFun! I used milling machines quite a bit in plastic classes that I took back in the 90's. I always had a blast with them:D




Those single brackets (femur and tibia joint) are a bit flexing and they do stress the joint, not healthy for the servo :rolleyes: (especially for the femur servo) I think. But that's the price for a more flexible and agile hexapod :p lol.Heavy, bulky brackets are overrated anyway;) Unless you were planning on carrying things, on Phoenix's back, you don't need them anyway. Great work on this, it is incredibly flexible!



So, you suggest I should post Oxyopus for the next contest? That's OK for me. I'm still working with it and I don't have any other project to enter right now.For sure! Contestants cannot win two prizes in a single contest and Phoenix is an awesome project by itself.


-Zenta (not Zentra :wink:)

Haha! My bad, I edited my original post;)

Matt
01-23-2008, 10:48 AM
Major kudos on this robot. Like everyone else I'm blown away by her fluid motion. I thought of micromagicsystems hexapod v4b as soon as I saw the first video so you certainly nailed that goal of emulating their successful lifelike motion.

Are you planning to start modularizing the walking and movement routines so you can use them to build navigation behavior?

Let me see if I can explain what I mean:
1) Creating many modular routines for movements: walk strait ahead, turning left, turning right, raise body, lower body, etc. (Already done it looks like)
2) Then you can use path planning software to figure out movement around the room: results are something like forward 4 feet, left 25 degrees, forward 3 feet, right 45 degrees, etc
3) Then you use your modular walking functions to execute the navigating.

I'm not sure how the sequencer and excel work though. It might be hard to evolve into that stuff from what you have so far. Do you know any programming languages?

Looking forward to seeing more of this great project!

DresnerRobotics
01-23-2008, 11:26 AM
Not to steal Zenta's thunder here, but I'm pretty sure he already has the basic walking modules dialed in. Those are usually the first step with any hexapod, and if you watch the end of the 1st, and some of the 3rd video, you can see the hexapod walking around a bit.

I'll let him explain the excel >> SEQ process and autonomy plans.

Dave
01-23-2008, 12:45 PM
Wicked cool. The mechanics look really nice. I'd like to see it walk around, as well.

I downloaded PEP and spent the past 20 minutes or so tinkering with it. Far out, man. I could mess around with this all day. This is the kind of stuff I was doing when I first started working for Trossen (well, the back-end math, anyway. I don't have the skills to make an interface like that in Excel). I'm going to have to learn some Norwegian so I can read your comments, though :)

kdwyer
01-23-2008, 02:13 PM
I don't know whether to squish it or eat it! VERY insect-like, very cool execution. I like the inverted servos on the leg ends, looks very good.
What's next, making it leap for your throat?

Zenta
01-23-2008, 02:58 PM
Major kudos on this robot. Like everyone else I'm blown away by her fluid motion. I thought of micromagicsystems hexapod v4b as soon as I saw the first video so you certainly nailed that goal of emulating their successful lifelike motion.
Hi Matt!
Thanks! The major difference between Phoenix and hexapod v4b is that v4b has onboard CPU doing all the math in realtime. While Phoenix is more like a marionette with all math precalculated. My goal is to have both. The advantage of using precalculated moves (done with PEP) is that you can make very creative moves, not only walking. A combination would be awesome!



Are you planning to start modularizing the walking and movement routines so you can use them to build navigation behavior?

Let me see if I can explain what I mean:
1) Creating many modular routines for movements: walk strait ahead, turning left, turning right, raise body, lower body, etc. (Already done it looks like)
2) Then you can use path planning software to figure out movement around the room: results are something like forward 4 feet, left 25 degrees, forward 3 feet, right 45 degrees, etc
3) Then you use your modular walking functions to execute the navigating.
Yes, you got it. I've been thinking of making many small sequences and run them with the GP-sequencer (all sequences stored on a EEPROM on SSC32).



I'm not sure how the sequencer and excel work though. It might be hard to evolve into that stuff from what you have so far. Do you know any programming languages?

Looking forward to seeing more of this great project!
I'm not sure if I understood you here :confused: . But you are able to create gaits with PEP... I know a little about basic and C.

-Zenta

Zenta
01-23-2008, 03:23 PM
Wicked cool. The mechanics look really nice. I'd like to see it walk around, as well.

I downloaded PEP and spent the past 20 minutes or so tinkering with it. Far out, man. I could mess around with this all day. This is the kind of stuff I was doing when I first started working for Trossen (well, the back-end math, anyway. I don't have the skills to make an interface like that in Excel). I'm going to have to learn some Norwegian so I can read your comments, though :)
Hi Dave!
It's not easy to try mind others thinking lol ;), especially with norwegian comments...
I think you can see some walking on my vids? For the time Phoenix is without the SSC32 servo controller, Oxyopus has it.. So I'm not able to make more walking right now, maybe later.

I've attached the latest version of PEP ver 1.04. It's packed with .rar not zip, so you have to rename it first then unrar it. EDIT: It's attached to the main post in this thread.
-Zenta

Alex
01-29-2008, 12:45 PM
Hey Zenta,

I just wanted to let you know that I added .rar for attachments choices. I tried doing it the other day, but ran into some problems. It should be working now, but if not, be sure to let me know:)

Zenta
02-05-2008, 04:20 PM
Hey Zenta,

I just wanted to let you know that I added .rar for attachments choices. I tried doing it the other day, but ran into some problems. It should be working now, but if not, be sure to let me know:)

That's great Alex! I've added a new PEP (same version but with a minor bug fix). I'll post a manual as soon as I'm finished with it. Btw I attached it to the main post in this thread.

-Zenta

Zenta
02-13-2008, 05:25 PM
Hi!

For some days ago I heard my Phoenix crying to get some attention... She has been very upset after I took her SSC32 controller board for Oxyopus :genmad:

And when she finaly caught my attention she whispered : "Give me a pen!"
A pen? I said, what do you need that for?

She got the pen, and this is what she did:


http://www.youtube.com/watch?v=P0pJ1RALDZ0


I have never seen a hexapod doing that before ! ;) Anyone?

(Sorry about the messy wires above the SSC32...)

This is more like a demonstration of the accuracy of her movements. The IK calcualtions has a resolution of 1 mm while writting. You might see that the letters are a bit uneven. That's caused by the unaccuracy of the MG geartrain in the servo.

This is probably not the most useful ability for a hexapod. Maybe she can write a message in the sand outside ;) Or tag an object ?

Anyway, it was a bit funny seeing her write though...

http://i214.photobucket.com/albums/cc6/ZentaOlbaid/HiTrossenRobotics.jpg

DresnerRobotics
02-13-2008, 05:30 PM
Haha! Excellent Zenta!

I wish I could wrap my mind around I.K. calculations as well as you have, truly amazing stuff.

Alex
02-13-2008, 09:59 PM
That is absolutely incredible Zenta! How on Earth did you do that?

Just 7 hours before your post here, you said that you got an idea (http://forums.trossenrobotics.com/showpost.php?p=6288&postcount=5) from PosterBot's thread. Kudos!

jrowe47
02-14-2008, 12:25 AM
Wow! Kudos, man, beautiful.

Dave
02-14-2008, 11:28 AM
Well, I'm speechless.

Also: In a brief, informal poll, we've determined that Phoenix has better penmanship than anyone in our office.

Matt
02-14-2008, 11:35 AM
WOW. Allow me a moment to pick my jaw up off the floor. I cannot believe that you are getting that kind of resolution out of hobby servos. Also, that you are getting it on the end of extensions that long. I was impressed before, but this is simply top shelf. When do we get to see him walk around and sneak into rooms to scare the hell out of girls?

Thanks for the post. Flattery will get you everywhere with us :)

MYKL
02-14-2008, 02:02 PM
Its innovations like this that make this 'hobby' so exciting.

I am encouraged beyond measure to find a person working on a GUI that is so robst yet simple at the same time.

I'd like to see a setup like that done for a Biped. Can your GUI be tweaked for one? This is looking closer and closer to the kind of interface animators use to create 3D animations. The IK/revIK based upon skeletal joints.

Beautiful.

^_^

Zenta
02-14-2008, 04:12 PM
HI!

Thank you all for your nice comments! It means alot for me.
My wife wasn't impressed at all :confused: . She simply said: "I supose she only do what you tell her to do?" .... Ehhh it's not that simple I tried to explain, but OK you are correct, I said. ;)
---
Alex: Yes I said I got an idea (http://forums.trossenrobotics.com/showpost.php?p=6288&postcount=5) from PosterBot's thread, but I wasn't that fast LOL. I began working with this idea last weekend.

The code for generating a letter is actually quite simple. And it's pretty easy to use. You only define the start position of the "pen leg". Then enter the letter you want to write (in the Write Sequences section) and then hit a button called "Generate letter". Here is a screenshoot of the main sheet of PEP ver 1.05:
http://i214.photobucket.com/albums/cc6/ZentaOlbaid/PEP105Write.jpg

In this example I entered the letter "R" in the comment field. Click the generate button and PEP starts to calculate all 20 steps it takes to make a "R". It takes about 320 steps to write "Hi Trossen Robotics!" I'm not finished with implementing all letters in the alphabet yet. But I'll release the PEP ver 1.05 when its done. (If someone would be interested).

Zenta
02-14-2008, 04:32 PM
Its innovations like this that make this 'hobby' so exciting.

I am encouraged beyond measure to find a person working on a GUI that is so robst yet simple at the same time.

I'd like to see a setup like that done for a Biped. Can your GUI be tweaked for one? This is looking closer and closer to the kind of interface animators use to create 3D animations. The IK/revIK based upon skeletal joints.

Beautiful.

^_^

Hi MYKL!

Thanks, I've been thinking about bipeds for a while and I think it might be possible to create a "PEP" sheet for a biped too. Doing IK calculations on more than 3 DOF is much harder, maybe a matrix setup or just doing 3DOF IK calculations combined with FK (forward kinematics) might be a solution. What I mean about the IK/FK combination? If you have a 4DOF leg you first do a FK on one joint and then do a 3DOF IK calculation based upon this. My math skills are limited so I think I've to study that part much more. LOL

Matt
02-14-2008, 04:52 PM
That's pretty funny about the wife. Nothing like having dozens of hours dismissed with, "Yeah, but will it help clean the house?" :tongue:

Zenta, have you had a chance to look at the concepts of the TRS (http://www.trossenrobotics.com/tutorials/trossenroboticssystem.aspx) yet? What you have going here is the basis for what we call the Algorithm Library (http://www.trossenrobotics.com/tutorials/TRS5.aspx). Lately we have been discussing converting the project into an open source one. We may post it up on site or over at google code or sourceforge and let the community start finishing it as a group effort. Who ever tackles the Algorithm Library should really interface with you on all this incredible work you've done. Like MYKL just mentioned, these same algorithms you have been working on can be converted for use by others with other robot formats.

I think maybe we should see if Chuck would want to help convert these into blackbox functions in .NET or Java? I'm soooooo tired of only multimillion dollar industrial robotics companies having access to advanced inverse kinematic functions. There should be some free functions out there in various languages that anyone can grab and use. Everyone keeps reinventing this wheel.

Zenta
02-14-2008, 05:12 PM
Hi Matt,
I've not studied the TRS part yet, but it looks VERY interesting. I'll try to look into it soon and give you a better answer. Right now I can't see how my Excel sheet can be used, but I think I got the picture of it.

Matt
02-14-2008, 06:58 PM
cool, let me know what you think.

The excel sheet itself wouldn't be used. The math inside it is where the value is. That can be used to create the same functionality in other languages.

darkback2
02-14-2008, 11:26 PM
Quick Question...How much weight can this platform carry? Only reason why I'm asking is because it would be really cool to mount a laser ranger finder on top so that the computer could map pathways for it to follow. I know...I'm not supposed to play with other peoples toys.

It is super sweet though.

Che

Alex
02-15-2008, 09:57 AM
Only reason why I'm asking is because it would be really cool to mount a laser ranger finder on top so that the computer could map pathways for it to follow.

That'd be awesome! I'd love to see this creepy crawly navigating on it's own all throughout a house.

Too bad laser range finders cost 2k or more though:(

Zenta
02-16-2008, 12:29 PM
Hi!

I just want to mention that Lynxmotion are going to offer Phoenix as a hexapod kit.
Here is a picture of the Lynxmotion version:
http://i214.photobucket.com/albums/cc6/ZentaOlbaid/phoenix1-1.jpg

If you want more information about the LM Phoenix kit, visit this thread (http://www.lynxmotion.net/viewtopic.php?t=2884).

Zenta
02-16-2008, 01:07 PM
Quick Question...How much weight can this platform carry? Only reason why I'm asking is because it would be really cool to mount a laser ranger finder on top so that the computer could map pathways for it to follow. I know...I'm not supposed to play with other peoples toys.

It is super sweet though.

Che
Hi,

The payload capacity depends a bit on wich type of gait method you want to use. The tripod gait is the most demanding since only one leg is holding the body one the one side.

But believe it or not: I did a payload test right now. And Phoenix was able to tripod walk with a payload of 2,5 kg! :robotsurprised: So a payload of 1 kg was no problem at all. Total weight of my Phoenix is 1,8 kg.

darkback2
02-16-2008, 01:10 PM
Ok...another idea would be a number of wireless cameras and vision software. Also you could mount pressure sensors on the bottom of each foot. That way phoenix could know if a foot is on the ground or not. laser range finders just look cooler.

Zenta
02-16-2008, 01:54 PM
Ok...another idea would be a number of wireless cameras and vision software. Also you could mount pressure sensors on the bottom of each foot. That way phoenix could know if a foot is on the ground or not. laser range finders just look cooler.

Yes, that sounds more useful;)

I think the battery began to worn out but I managed to get a video of her while rotating ripple walk with 2,5 kg on her back. But I would say that a payload of maximum 1,5 kg would be more realistic.

http://www.youtube.com/watch?v=fsAUTXNeUhA

knifedge
02-17-2008, 09:42 PM
Zenta, you're a genius for the imagination you demonstrated in Phoenix's behaviors.

I love the idea of your Oxyopus project. I would love to work on a 24 DoF bot. In the past, I've felt that six legs weren't enough to do what I want to do. With an 8 legged bot, you could do cool things like use 6 legs for walking, and 2 legs to manipulate the environment in interesting ways (like playing with a box or carrying something). If you get a chance, could you post the joint information for Oxyopus?

Zenta
02-19-2008, 11:28 AM
Hi Knifedge!

Thanks for your comments!
I didn't plan to reveal any details about Oxyopus, but since you are mention her too I've got a little video of her while doing some walking on six legs. It's just a smal demonstration for now... ;)


http://www.youtube.com/watch?v=Ug1ajSmjNAc

MYKL
02-19-2008, 12:15 PM
Hi MYKL!

Thanks, I've been thinking about bipeds for a while and I think it might be possible to create a "PEP" sheet for a biped too. Doing IK calculations on more than 3 DOF is much harder, maybe a matrix setup or just doing 3DOF IK calculations combined with FK (forward kinematics) might be a solution. What I mean about the IK/FK combination? If you have a 4DOF leg you first do a FK on one joint and then do a 3DOF IK calculation based upon this. My math skills are limited so I think I've to study that part much more. LOL

I wants that! Yesssss.... It would be my new preciousss.... Mmmm....

So it would be very much like animating in 3D with the IK/FK and the bones and the constraints and the oh my gawd?

Yessss...

^_^

knifedge
02-19-2008, 11:23 PM
That's an excellent teaser for Oxyopus. I'll let you surprise us with more on Oxyopus next month. :)

For now, just watching the Phoenix videos again, I'm struck by how much more elegant Phoenix looks compared to other hexabots (including the one I have next to me). Her long legged design allows a greater range of motion. By using the box, you've shown how she could easily rise above an obstacle. Also, her rocking behavior could be used to get different perspectives needed to classify or 3D map an object when using visual software. Again, great work!

Zenta
02-24-2008, 05:42 PM
Hi,

To day wasn't my luck day...:( I had some spare time and I wanted to make some new sequences for my Phoenix while she was playing with the box. So far so good, but suddenly my computer broke down and I had to reinstal OS and everything. After several ours we was up and running again. But after a few minutes Phoenix began to struggle and she could barely stand on her feets (read legs...). I was wondering; are you sick? are you drunk or something? ;)


http://www.youtube.com/watch?v=-0oyqgMVGDQ

I thought it was a bit funny to see her struggle with low on battery. LOL

Matt
02-24-2008, 09:07 PM
Looks like someone got into the liquor cabinet :robotsurprised:

Alex
02-25-2008, 11:05 AM
Wow! That was actually pretty life-like. Low energy definitely affects fleshies strangely.

SN96
02-25-2008, 05:26 PM
Zenta,

The life like movement is insane with your bot! It is so fluid like you forget that its using servo motors! It moves like it has muscles.

MYKL
02-26-2008, 04:02 PM
You can't be using LiPos on that then.

Right?

My 'bot just passes out when he can no longer weeze the juice.

^_^

Zenta
02-26-2008, 04:21 PM
You can't be using LiPos on that then.

Right?

My 'bot just passes out when he can not longer weeze the juice.

^_^

Hi,

For the time I'm using Ni-MH 2700 mAh 6v. But I'm actually waiting for two smaller BEC's 8-15 Ah, because I'll try to use LiPo's for Phoenix too.

Do you use separate battery for the electronics? I use a 9v battery for the SSC32 controller, I think that's the reason for why she act so funny when going low on servo-juice ;). The servos get very low power but the electronics get stable power.

MYKL
02-26-2008, 04:46 PM
With six to eight legs to tote around whateveryouwill that is a very wise thing to do. Most valued R/C vehicles have the same kind of setup. Your machine is state of the art my friend. Only IMHO because you are one intelligent and enterprising fella.

mdenton
03-07-2008, 05:02 AM
Hi Matt!
Thanks! The major difference between Phoenix and hexapod v4b is that v4b has on board CPU doing all the math in real time. While Phoenix is more like a marionette with all math precalculated. My goal is to have both. The advantage of using precalculated moves (done with PEP) is that you can make very creative moves, not only walking. A combination would be awesome!


Hi Zenta,

I disagree with your theory of precalculated moves being more creative? With my real time engine, you can walk in any direction, and rotate and translate the body in any direction in real time. If needed it would also be possible to record this and play the moves back.. so there are no limitations. :)

This video show my V4b hexapod walking, and then stopping before doing some body rotate. The only reason it does not rotate the body while on the move, is due to the way I configured the control system for this video. I only had one joystick, and so I used a joystick button to switch between walking and body rotate/translate.


http://www.youtube.com/watch?v=5hbAMFAnui4

Matt
www.micromagicsystems.com (http://www.micromagicsystems.com)

Zenta
03-07-2008, 12:05 PM
Hi Zenta,

I disagree with your theory of precalculated moves being more creative? With my real time engine, you can walk in any direction, and rotate and translate the body in any direction in real time. If needed it would also be possible to record this and play the moves back.. so there are no limitations. :)

This video show my V4b hexapod walking, and then stopping before doing some body rotate. The only reason it does not rotate the body while on the move, is due to the way I configured the control system for this video. I only had one joystick, and so I used a joystick button to switch between walking and body rotate/translate.

Matt
www.micromagicsystems.com (http://www.micromagicsystems.com)

Hi Matt

What I mean by creative moves is like this one:

http://www.youtube.com/watch?v=IqWKGh4XLbk

Or like this one:

http://www.youtube.com/watch?v=P0pJ1RALDZ0

OK?

SN96
03-07-2008, 05:10 PM
OMG! I did not know Phoenix actually wrote that, I thought you pre wrote it and then took the picture. Impressive!

jdolecki
03-07-2008, 06:04 PM
Have you ever thought of putting a body on it?

I bet you could scare the heck out of people with a spider that size.

Like the Pleo from UGOBE.

I rather have a freaky looking spider than some green thing.

Droid Works
03-07-2008, 08:03 PM
Terrific job! This is what robotics is all about.

Zenta
03-09-2008, 07:59 AM
Have you ever thought of putting a body on it?

I bet you could scare the heck out of people with a spider that size.

Like the Pleo from UGOBE.

I rather have a freaky looking spider than some green thing.
Hi!

No, I have not considered that, but it would be cool!
I know Matt Denton has done that with one of his hexapods. It looked like a six legged turtle, I think.

Zenta
03-09-2008, 08:00 AM
Terrific job! This is what robotics is all about.

Thanks!

Dave
03-10-2008, 02:13 PM
Seconding this:


Have you ever thought of putting a body on it?

I bet you could scare the heck out of people with a spider that size.

Like the Pleo from UGOBE.

I rather have a freaky looking spider than some green thing.

I've met some tarantulas with quite a bit of personality. A robotic arthropod with a Pleo-esque personality seems perfectly reasonable to me. People will inevitably argue that it's not "cute" enough, but of course I disagree. How could you not love a face like this:

Zenta
03-10-2008, 04:47 PM
Hi!

I've been working with a sequence project lately demonstrating Phoenix playing with the box again. It took me 3 late evenings to tweak and adjust the moves to make it right. But it was a bit fun though....:D

Enjoy!


http://www.youtube.com/watch?v=NUMGpDTm59w

drattino
03-10-2008, 06:08 PM
Looks like a head crab from Half-life, just putting that out there.

Alex
03-10-2008, 06:58 PM
Looks like a head crab from Half-life

ha! totally:D

MYKL
03-11-2008, 11:47 AM
Unbelieveably cool.

How about a sequence where the 'bot walks over the box without changing altitude. It lifts its main body high enough to clear the obsticle then walk right over it while the legs make up for the varied hight in terrain.

Then mount a can of silly string to approximate spinnerettes and have it unload on the box...

Dirty spider.

Zenta
03-11-2008, 12:23 PM
Unbelieveably cool.
Thanks!



How about a sequence where the 'bot walks over the box without changing altitude. It lifts its main body high enough to clear the obsticle then walk right over it while the legs make up for the varied hight in terrain.

That should not be a problem. Maybe I'll try that next time.



Then mount a can of silly string to approximate spinnerettes and have it unload on the box...
Ehm:( Pardon my bad english but I'm not sure what you mean with "silly string" and "spinneretters"?

kdwyer
03-12-2008, 03:07 AM
Oh, c'mon now, every technological society knows about Silly String, that spray can of love and joy.

I just haven't seen any cans sized just right for this bot though. See, gotta hand-build everything.

Spiders spin their webs from spinner-ettes, ie. small spinners.

Pardon my slow typing.

Zenta
03-12-2008, 03:58 AM
Oh, c'mon now, every technological society knows about Silly String, that spray can of love and joy.

I just haven't seen any cans sized just right for this bot though. See, gotta hand-build everything.

Spiders spin their webs from spinner-ettes, ie. small spinners.

Pardon my slow typing.

Ah!:o LOL Of course, I know what you mean. Yeah that would be fun! Have to see if I can find a small can one day.

Matt
03-12-2008, 11:52 PM
Then mount a can of silly string to approximate spinnerettes and have it unload on the box...


OMG thats a great idea!

Silly string was originally an attempt at making a new packing material BTW :p

Zenta
04-01-2008, 02:46 PM
Hi,
I'm finaly done with my documentation (manual, how to) for PEP, hopefully some of you in the robotic community can use this PEP sheet for your own hexapod projects. I've also added some extra functions: true rotation along all axis (not only the simplified Pitch and Roll function) and the writing function (I've not defined all letters yet..). But a cool part is that its also possible to define centre point of rotation in all dimensions also in height (Y) not only X and Z. (ehm, yes I managed to mix up the Y and Z axis LOL.

The documentation .pdf file was too large to be uploaded here. But you can get the files from Lynxmotion Phoenix project page (http://www.lynxmotion.com/images/html/proj098.htm).
Here is a screenshoot of PEP ver 1.06:
http://i214.photobucket.com/albums/cc6/ZentaOlbaid/Body-Coxa-hoved.jpg

LinuxGuy
04-06-2008, 11:57 PM
Have you ever thought of putting a body on it?

I bet you could scare the heck out of people with a spider that size.
Phoenix is an insect. Spiders have eight legs. :happy:

8-Dale

Adrenalynn
04-10-2008, 02:15 PM
Wow! Her motions are so fluid, so lifelike, so believable! That is TREMENDOUS kinematics!

I'm blown away!

Adrenalynn
04-10-2008, 02:23 PM
Phoenix is an insect. Spiders have eight legs. :happy:

8-Dale


Phoenix is an insect. Spiders have eight legs. :happy:

8-Dale

She also doesn't have two distinct body sections - cephalothorax and abdomen
Spiders also have seven leg segments - from the ground: claw, tarsus, metatarsus, tibia, patella, femur, coxa. Spiders have either two or three claws, depending upon the family...

Sorry - I'm a spider-nut...

That said, the vast majority of people won't be counting legs or body segments (let alone leg segments) if that thing is comin' at 'em in a dark room. :P (Me, I'd wanna pick her up and play with her. If she likes to off 'squeeters, she can stay upstairs. If she's overly venomous, she needs to stay downstairs with all the black widows I relocate there... ;)

Semicton
04-10-2008, 04:22 PM
wow this is incredible. Seeing all these types of projects sometimes makes me feel i am in over my head and will never be able to compete in any of the contests. I'm feeling a little envious right now cause this is a really kick ass robot. We need a noob contest too! For the people who can't afford a full blown custom shop and thousands of dollars to compete :)

Cool though, so you wrote the entire app from scratch for this? Man, I wish I could spend about 90 days just looking over your shoulder and asking you a lot of questions. :)

Zenta
04-20-2008, 01:49 AM
Hi!

Since I have problem to upload files as an attachment for an unknown reason (Thanks to Alex who tried to help me), I have just uploaded the PEP manual and the spreadsheet to the TRC "Downloads Library". I was a bit unsure where to place the PEP sheet but you find it in the "Kinematics / Algorithm" section.

Alex
04-20-2008, 02:36 PM
Awesome Zenta, so is everything working for you now with uploading?


wow this is incredible. Seeing all these types of projects sometimes makes me feel i am in over my head and will never be able to compete in any of the contests. I'm feeling a little envious right now cause this is a really kick ass robot. We need a noob contest too! For the people who can't afford a full blown custom shop and thousands of dollars to competeHusko! Man, our discussion the other night (or was it last night?) in the TRC Chat about the controls you wanna build could easily get you in the front runnings of one of our contests. Obviously I can't say you'd win or loose, but provided you give some great documentation in your entry thread, it'll definitely boost your rankings when we vote. Remember, entries don't have to be an actual robot, it can very well be some sort of tool (or in your case, a set of tools) that people can use:D I don't want to hijack this thread or anything so if you or anyone else has questions about this, either contact me or post your questions in the Questions sticky (http://forums.trossenrobotics.com/showthread.php?t=1136) in the Project Showcase forum.

Zenta
04-20-2008, 03:41 PM
Awesome Zenta, so is everything working for you now with uploading?


Hi Alex,
I still get the same upload error when I'm trying to upload an attachment to this or other threads. But uploading files to the Gallery or the Downloads library works fine.

Alex
04-20-2008, 03:57 PM
k, I'll look into this more tomorrow when I get to work.

Zenta
06-04-2008, 01:31 PM
Hi!
For a long time I've been puzzled of how Matt Denton (micomagicsystems) managed to program the balance gesture engine (http://www.micromagicsystems.com/#/balancegesture/4517267257). Who hasn't been fascinated when watching his hexapod walking so smooth and elegant. For example, pay extra attention to the very first second of this video of the ic hexapod (as soon as you see the hexapod of course :wink: ), then you can see that the whole body of the hexapod is trying to balance towards the lifted legs. I'm pretty sure that this is caused by Matt Denton's excellent balance gesture.
Anyway, I think I've solved the balance gesture thing.. :D For know I've just added it to 2D (X and Y axis). I've posted a video of Phoenix doing some simple balancing on youtube:


http://www.youtube.com/watch?v=Yzi6C7-LcVQ

This is only a demonstration where Phoenix is balancing her body while one leg is moving around.
Of course this ability is not useful on an excel sheet (PEP) but it would be great to have on an onboard brain. Especially for terrain adaption, this should be a very useful ability.

Adrenalynn
06-04-2008, 02:14 PM
So smoooth and organic! Nice kinematics! Very impressive absolutely beautiful!

pladoh
06-11-2008, 09:02 PM
seroiusly if that was an inch wide i would squash it immediately if i didnt know it was a robot,
it is so...
real?

pladoh
06-11-2008, 09:03 PM
is that programmed planned move ment or is it anautomous?

Zenta
06-16-2008, 03:20 PM
Hi!

For information I've started a little blog about building and Tuning the Lynxmotion Phoenix hexapod (http://forums.trossenrobotics.com/blog.php?b=105).

http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenixlm014_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=375&c=newimages)

Zenta
07-13-2008, 05:28 PM
Hi!

Here is a little video of me (only my hands.. http://www.lynxmotion.net/phpbb/images/smiles/icon_wink.gif ) playing with my Lynxmotion Phoenix remote controlled with PS2, running Xan's (from the Lynxmotion forum) code!

Next step is start playing with the GP sequencer + Xan's code.


http://www.youtube.com/watch?v=NcsRiO4buOE

Xan are still working with the code, but it seem to work pretty well so far.

-Zenta

A-Bot
07-13-2008, 10:12 PM
Xan are still working with the code, but it seem to work pretty well so far.


Yeah I'd say it's working pretty well. I like the red. I need to get me one of those!

LinuxGuy
07-16-2008, 10:13 PM
Here is a little video of me (only my hands.. http://www.lynxmotion.net/phpbb/images/smiles/icon_wink.gif ) playing with my Lynxmotion Phoenix remote controlled with PS2, running Xan's (from the Lynxmotion forum) code!
Very nice, Zenta! You are one of the most awesome robot creators I have ever seen. :veryhappy:

8-Dale

Zenta
08-03-2008, 04:34 PM
Hi,

I've modified Xan's code and added a GP player and two different gaits. In this test video I'm controlling Phoenix with a PS2 remote. But I'm struggling with some bugs with the remote and its very hard to make a precise move. You can see some glitches of some legs moving in a bit off path. With a RC remote this was much easier, so that will be the next step.

Sorry for the long movie. http://www.lynxmotion.net/phpbb/images/smiles/icon_redface.gif


http://www.youtube.com/watch?v=IXes65v-pV8


It is just a test, and to demonstrate the power of combining live control and precalculated sequences. http://www.lynxmotion.net/phpbb/images/smiles/icon_biggrin.gif

BTW, the gait I'm using here is a 6 steps tripod gait and a spesial 9 steps ripple (I'm calling it quadripple) gait.

-Zenta

4mem8
08-04-2008, 12:36 AM
Very nice Zenta, I would love to have you programming skills, This is holding me up big time in my robotics. Keep up the good work.

crabfu
08-04-2008, 12:39 AM
that is just absolutely beautiful... man.... wow :)

-Crabfu

Zenta
08-04-2008, 01:41 AM
Thanks!

Crabfu, I'm thinking of buying a Spectrum DX6i (cheaper than the DX7) to control Phoenix with. My father have the DX7. My old Graupner FM 4014 Transmitter with receiver worked well too, but I want the small recievers (and small antenna + legal ground control) from Spectrum. But before I buy one I need to check how the Spectrum receivers send the pwm pulses on each channels. My old receiver send them in a "puls train" meaning that within 20 ms it first send a puls (about 1.2 - 1.8 ms pulse) on CH1 then CH2 then CH3 and so on. That is very timesaving when doing a pulsin (from the Basic Atom Pro) on CH1, CH3 and CH5 then do a pulsin on CH2, CH4 and CH6, meaning that you can read all channels within about 25 ms. But if Spectrum's receivers send pulses on all channels at once (not in a train/serial) I've a problem, because reading of all six channel will take about 110 ms.

So I'm gonna connect my fathers Spectrum on to a oscilloscop to check taht before I buy one.
Does anyone know something about this.

crabfu
08-04-2008, 02:16 AM
Wow cool... I don't know anything about that mumbo jumbo, sorry! But would be cool to have a nice transmitter for that critter. I'd love to learn all this stuff one of these days, that just looks way too cool, I'm still in awe :)

-Crabfu

Xan
08-04-2008, 05:05 AM
Hi Zenta,

I just placed a reaction on the LM site to but once again: COOL! I love what you did with the combination of real time calculations and sequences!

Xan

Zenta
08-04-2008, 06:55 AM
Hi Zenta,

I just placed a reaction on the LM site to but once again: COOL! I love what you did with the combination of real time calculations and sequences!

Xan

Hi Xan,

Nice to see you here at TRC too!
Thanks to you and your work with the code I think the "Phoenix consept" are going to be pretty cool. I'm planning to modify a RC transmitter adding about 10 switches/function to one RC channel used as input buttons to command Phoenix for different PEP made sequences. I'm planning to make several funny sequences of Phoenix playing, kicking, walking over ++ the box.

-Zenta

Zenta
08-28-2008, 03:50 PM
Hi,
I've spent some more time studying kinematics lately. I've worked more with Xan's code. If you study the subroutine BodyIK you can see that it takes care of Y-rotation and the pitch and roll rotation. I'm guessing Xan used the formulas I used in the PEP sheet for the roll and pitch calculation.
To be honest I've never been pleased with these simplified rotations (pitch and roll), because they are not real body rotation. They only uses FTAN to adjust the BodyIKPosY value.
If you compare these body rotations with the rotations Matt Denton demonstrates on his videos you'll understand what I mean...
Anyway, I've rewrote the BodyIK subroutine:

BodyIK [PosX, PosZ, PosY, BodyOffsetX, BodyOffsetZ, RotationY]
;Calculating totals from center of the body to the feet
TotalZ = BodyOffsetZ+PosZ
TotalX = BodyOffsetX+PosX
;PosY are equal to a "TotalY"

;Successive global rotation matrix:
;Math shorts for rotation: Alfa (A) = Xrotate, Beta (B) = Zrotate, Gamma (G) = Yrotate
;Sinus Alfa = sinA, cosinus Alfa = cosA. and so on...

;First calculate sinus and cosinus for each rotation:
gosub GetSinCos [TOFLOAT(BodyRotX)]
sinG = sinA
cosG = cosA
gosub GetSinCos [TOFLOAT(BodyRotZ)]
sinB = sinA
cosB = cosA
gosub GetSinCos [TOFLOAT(BodyRotY+RotationY)]

;Calcualtion of rotation matrix:
BodyIKPosX = TotalX-TOINT(TOFLOAT(TotalX)*cosA*cosB - TOFLOAT(TotalZ)*cosB*sinA + TOFLOAT(PosY)*sinB)
BodyIKPosZ = TotalZ-TOINT(TOFLOAT(TotalX)*cosG*sinA + TOFLOAT(TotalX)*cosA*sinB*sinG +TOFLOAT(TotalZ)*cosA*cosG-TOFLOAT(TotalZ)*sinA*sinB*sinG-TOFLOAT(PosY)*cosB*sinG)
BodyIKPosY = PosY - TOINT(TOFLOAT(TotalX)*sinA*sinG - TOFLOAT(TotalX)*cosA*cosG*sinB + TOFLOAT(TotalZ)*cosA*sinG + TOFLOAT(TotalZ)*cosG*sinA*sinB + TOFLOAT(PosY)*cosB*cosG)
return

I've also modified other parts of the code.
BTW, I've just bought a Futaba 7C 2,4 GHz (http://2.4gigahertz.com/systems/futk7000.html) RC remote control. This gives me much better control. I'm also going to modify the 7C. Posting more info about that later.
Here is a little video demonstration:


http://www.youtube.com/watch?v=_2Jc44GLTcU

My wife are holding the cell phone camera :wink: , she was actually impressed this time! :D Sorry for the bad quality. When I find time for it I'll get my Sony video camera and make a real video/film.

Zenta
09-22-2008, 02:49 PM
Hi,
I'm now very proud to present Balancing Phoenix!
Here are two pictures of Phoenix balancing her body while lifting one leg on top of some 5645 Hitec boxes :D

http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenixlm026_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=722&c=member&imageuser=1535)

Another angle of view:

http://forums.trossenrobotics.com/gallery/files/1/5/3/5/phoenixlm027_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=723&c=member&imageuser=1535)

I've modified Xan's code alot lately and I've implemented a Balance Mode that take care of balancing the body in all dimensions (XZY), translate and rotate. This is similar to Matt Denton's balance gesture (http://www.micromagicsystems.com/#/balancegesture/4517267257).
The pictures show Phoenix RC controlled when I remotely move her leg on top of the boxes.
Now Phoenix can walk with three different gaits (tripod, quadripple and wave). I can anytime switch between normal walking and balance walking.

I think that the balance ability is a major improvement and a key feature when it comes to terrain adaption. So far I've been impressed of what is possible with the Basic Atom Pro, but I think terrain adaption might be too hard for it. But we have to try! :p

And here is a little demonstration video:

http://www.youtube.com/watch?v=72MY5GuHSpA

-Zenta

Adrenalynn
09-22-2008, 03:03 PM
Very organic looking - that's amazing!

Zenta
09-23-2008, 02:15 PM
Very organic looking - that's amazing!

Thanks Adrenalynn!

Maybe I should call the balance mode for "organic mode" ;)

Adrenalynn
09-23-2008, 05:28 PM
That's not a bad idea if you think about it. When you were changing gaits in balance-mode, I was reminded of watching insects and the way they alter their gate when climbing twigs and rocks and scurrying along - "organic" is probably more coined than "biomimetic" - but it's a heck of a lot easier to type/say/think. :)

4mem8
09-24-2008, 12:55 AM
Zenta: Simply amazing, You have my FULL attention with this setup, You are a true roboticist at heart. Maybe one day I will have a go at this.

Zenta
09-24-2008, 04:42 PM
Zenta: Simply amazing, You have my FULL attention with this setup, You are a true roboticist at heart. Maybe one day I will have a go at this.

Thanks 4mem8! Just have to say that Matt Denton's work have inspired me alot.

Adrenalynn: biom.. what? ;)

Adrenalynn
09-24-2008, 08:56 PM
Exactly.

Zenta
10-18-2008, 03:39 AM
Hi,

I've been in the video editing mode lately. Here is a little video for demonstrating a little precalculted sequence I'm using to make Phoenix place her legs in a new pose.


http://www.youtube.com/watch?v=SYRehpTxbik

-Zenta

4mem8
10-18-2008, 04:58 AM
Oh so cool Zenta, Just amazing, Great work. Love the black dome as well. I admire your work.

Migs
10-25-2008, 06:34 AM
So Zenta:

Two things:

1. Tell us more about yourself. I mean, what you do in real life, and all. I think all of us would like to know a little more about the human behind the hexapod. What made you do it? What does your family think (we all know what the Mrs. thinks). I inadvertently try to compare myself to you (of course I am several decades behind in my robotic achievements), but it will be cool to know how you got to where you are.

2. After your success with Phoenix, did you get any sponsorship or help (aside from winning some prize money)? I noticed on this thread that you took an SSC-32 off Phoenix for another robot. I don't know how you are financially, but I'll mail you another if you really miss it. (God knows you will make it sing!)

Keep up the great work, your achievement is an inspiration to us all. -Migs

Zenta
10-27-2008, 11:30 AM
1. Tell us more about yourself. I mean, what you do in real life, and all. I think all of us would like to know a little more about the human behind the hexapod. What made you do it? What does your family think (we all know what the Mrs. thinks). I inadvertently try to compare myself to you (of course I am several decades behind in my robotic achievements), but it will be cool to know how you got to where you are.

Hi,

Well I told a bit of myself at the first page in the "Introduce yourself!" (http://forums.trossenrobotics.com/showthread.php?t=1394) thread. I look at myself as an ordinary family father. And as for many others I have limited amount of time to offer into my hobbies, the time issue are often solved by not watch TV..;). Since I was a little boy I've always been inspired by robots. But I started more seriously with hexapods in 2006. My kids loves the robots and my wife have started to accept my intens interest. Actually she did ask me about my next project! LOL.



2. After your success with Phoenix, did you get any sponsorship or help (aside from winning some prize money)? I noticed on this thread that you took an SSC-32 off Phoenix for another robot. I don't know how you are financially, but I'll mail you another if you really miss it. (God knows you will make it sing!)

Keep up the great work, your achievement is an inspiration to us all. -Migs

Thanks!

I don't have any official sponsorship, but Lynxmotion has provided me with "some free parts".....;). Don't worry about the SSC32's..

No0bert
11-19-2008, 07:03 PM
This is so realistic and lifelike, I love it. I have made many robots recently, most are PIC or ATMega based, and I thought I was willing to get into hexapods. I google "hexapods" and get this heavenly page in the search results. I thought this was a plausible project I could do. So I ask the question, would you be willing to share the schematics/blueprints for the brackets, mounts, and legs?

And why use seperate servos for the body and legs, is it harmful to use servos that can be an "overkill". IE: a servo rated at a very high torque carrying something very light, or is it just for monetary reasons?

Obscene
11-19-2008, 07:28 PM
I'm astounded. The different balance techniques and walking gaits are amazing. I would love to be able to do this.

DresnerRobotics
11-19-2008, 08:23 PM
FYI- Trossen Robotics now carries the Phoenix Comprehensive Kit (http://www.trossenrobotics.com/lynxmotion-phoenix-hexapod.aspx) that contains everything needed to build your very own Wireless PS2 controlled Phoenix walker!

No0bert
11-20-2008, 05:22 AM
Ugh, but I am the typical Robot Hobbyist, and those guys dont have $1,000 ready to be shelled out :/, So I was getting at me doing it on my own

Zenta
11-20-2008, 09:57 AM
This is so realistic and lifelike, I love it. I have made many robots recently, most are PIC or ATMega based, and I thought I was willing to get into hexapods. I google "hexapods" and get this heavenly page in the search results. I thought this was a plausible project I could do. So I ask the question, would you be willing to share the schematics/blueprints for the brackets, mounts, and legs?

And why use seperate servos for the body and legs, is it harmful to use servos that can be an "overkill". IE: a servo rated at a very high torque carrying something very light, or is it just for monetary reasons?

Thanks!
I'm willing to share my drawings, but I've to warn you that its just hand drawn sketches. And there is already many people who has copied my Phoenix design, and thats ok. But I'm thinking, why not try to make your own unique design? Parts of Phoenix was inspired by one of Matt Dentons (micromagicsystems) hexapods.

I'm not sure if I understand what you mean about the servos, what kind of servos are thinking of? Its better to use overrated than underrated servos.

-Zenta

4mem8
11-20-2008, 10:44 AM
Exactly Zenta, If it's one thing I have learned in robotics you always seem to underestimate the servos and what load they can take with ease without destroying them, Not that I have destroyed any as they can be expensive. But get the best you can with your budget even if it stretches you a bit.

Xan
11-21-2008, 04:58 AM
Hi Tyberius!


FYI- Trossen Robotics now carries the Phoenix Comprehensive Kit (http://www.trossenrobotics.com/lynxmotion-phoenix-hexapod.aspx) that contains everything needed to build your very own Wireless PS2 controlled Phoenix walker!

Congratulations with your new stock kit! I was wondering why the number of hits per day on youtube increased about 15x. But I think I’ve found the reason ;)

Thanks for the credit on the trossen robotics website! (http://blog.trossenrobotics.com/index.php/2008/11/20/the-phoenix-hexapod-comprehensive-kit-is-here/) But as far as I know, I’m from the Netherlands though ;)

Xan

No0bert
11-21-2008, 02:55 PM
You said you could send me the schematics for your project, I would be so giddy if you were to, I would love to make something as sophisticated as this. If possible, could you PM me the blueprints for the parts? Or make it freely available to everyone?

Zenta
11-21-2008, 04:11 PM
You said you could send me the schematics for your project, I would be so giddy if you were to, I would love to make something as sophisticated as this. If possible, could you PM me the blueprints for the parts? Or make it freely available to everyone?

Hi,

I just uploaded my original hand drawings of my Phoenix's body and tibia part. You'll find it in the Data Center section under CAD files (http://forums.trossenrobotics.com/downloads.php?do=file&id=135). Yeah I know its not a CAD file, LOL. I'm pretty lowtech when it comes to drawings.

-Zenta

CyPrD
12-13-2008, 12:12 PM
Hi,

I have just registered here. I am stunned with Zenta's design. I've also seen the hexapod on the Mico Magic Systems site and I just love Phoenix and the way she behaves. Awsome job.
I have a book about robotics introduction, so I will have to open it again because I want to build this one (don't have that extra $1k to buy the kit :-( )
Guess that I will have hard time getting those parts done....

I'll stay tuned to this forum

Just found out that Micro Magic does the MSR-H01 Hexapod Robot Kit. Will that be a good start to make a replica of Phoenix?

One more thing, is Phoenix and the product from Micro Magic roughly the same size?

Zenta
12-13-2008, 02:22 PM
One more thing, is Phoenix and the product from Micro Magic roughly the same size?

Hi,
thanks for your credit in your previous post!

When I began with hexapods my second hexapod was inspired by Matt Dentons work (Micromagicsystems), especially the coxa design. You can see some equality from his v4b hexapod.

Lynxmotion contacted me and asked if they could make a Phoenix hexapod kit based upon my original Phoenix design.

I believe Phoenix and MSR-H01 (http://www.trossenrobotics.com/Hexapod-Robot-Kits.aspx) are not far from eachother in size. But they do look very different and one major difference is the tibia length. Both with their con and pros. I'll not go into that discussion ;)

CyPrD
12-14-2008, 06:20 AM
Zenta,

one more thing, I didn't read the specs for electronics in both kits, but do they allow you to connect other input devices? Like preasure sensors, more than one distance measuring device, light sensitive sensors etc. and do some programming with their signals?
Thanks

-= Edit =-
I can't wait to put my hands on one of those kits and start playing around :-)

DresnerRobotics
12-14-2008, 10:20 AM
The Comprehensive Phoenix Kit (http://www.trossenrobotics.com/lynxmotion-phoenix-hexapod.aspx) that we carry comes with a Basic Atom Pro and a Bot Board II, which has digital and analog I/O.

The Micromagic Hexapod Kits (http://www.trossenrobotics.com/micromagic-systems-hexapods.aspx) that we sell only include the HexEngine, which is essentially a gait generator. You would have to add a microcontroller to this bot to gain I/O capability.

CyPrD
12-18-2008, 12:52 PM
The Comprehensive Phoenix Kit (http://www.trossenrobotics.com/lynxmotion-phoenix-hexapod.aspx) that we carry comes with a Basic Atom Pro and a Bot Board II, which has digital and analog I/O.

The Micromagic Hexapod Kits (http://www.trossenrobotics.com/micromagic-systems-hexapods.aspx) that we sell only include the HexEngine, which is essentially a gait generator. You would have to add a microcontroller to this bot to gain I/O capability.

Hi,

I will most likely buy the logic that is in Phoenix Kit and build the chasis myself. My intensions are to add some autonomous behaveiour to the robot.
I am just confused with the gait process, I mean, the Micromagic has a hexengine with all the needed stuff and you have the stamp that does the logic and executes the prgoram.
If I have basic atom, where is the gait sequence stored? In the Basic Atom? How much space does it actually take?
Thanks and sorry for stupid questions (if they are) :confused:

J.

Resilient
12-18-2008, 02:56 PM
So whats actually happening when it's in balance mode? Are there gyros trying to keep the body still? Or is it trying to keep the weight distribution among all the legs on the ground even? Or something else? It looks very cool, but I am not very clear as to what is actually happening.

Zenta
12-18-2008, 03:05 PM
Hi,

I will most likely buy the logic that is in Phoenix Kit and build the chasis myself. My intensions are to add some autonomous behaveiour to the robot.
I am just confused with the gait process, I mean, the Micromagic has a hexengine with all the needed stuff and you have the stamp that does the logic and executes the prgoram.
If I have basic atom, where is the gait sequence stored? In the Basic Atom? How much space does it actually take?
Thanks and sorry for stupid questions (if they are) :confused:

J.

We are using a Basic Atom Pro. The program take some memory, but there is plenty left so don't worry. (I can't remember how much it takes). I believe Matt's hexengine are more accurate (proven by his CNC hexapod) and much much faster. Another major difference is that Xan's code are free and developed mostly by him (I and others in the community added some functions and improvements) and everyone can alter and change every bits in the code.

So again thanks to Xan and his work with the Phoenix BAP code!

sunithaya
12-19-2008, 08:51 AM
Zenta, beautiful work! and you have a very nice touch and control of the critter. I love the final goodbye! LOL!
It would be great to see a choreographed dance to music, you think you could be able to record your movement for playback?:-)
Biomimetics (or biomimicry) refers to the study and applications of methods that nature uses (through evolution of course) to solve problems like locomotion, climbing, balancing etc. Sort of reverse engineering, hehe, why reinvent the wheel, right? (I would say because it is fun and maybe we hit on another even better solution)
Keep up your great work!

LinuxGuy
12-20-2008, 04:23 AM
But get the best you can with your budget even if it stretches you a bit.
I would modify this slightly to say "But get the best for your application, even if it stretches you a bit."

People make a really big mistake by choosing servos by price alone, even if they do have specifications that match a given application. There is a lot of truth in the saying "you get what you pay for" with respect to electronic components and devices. From now on, for projects I plan to keep together, my base line servo is going to be the Hitec HS-645MG because it has a good torque, as well as a metal gear train. Yes, these are a stretch for me to get in any quantity due to the higher price, so I will be getting them 6 or 12 at a time, as I can get the money together for them, because I know they will be used in projects I build. I already need a few more of these for the new arm on W.A.L.T.E.R.

In fact, the HS-645MG (analog) servo is almost identical to the HS-5645MG (digital) servo. The only difference is the electronics board!

8-Dale

DresnerRobotics
12-20-2008, 10:44 AM
I'll chime in here even though its off-topic a bit...

The AX-12 is hands down the best bang for buck of any servo on the market. Double the torque of an HS-645 and its only $45. Fully digital, serial daisy chained, and every type of feedback you could want (positional, current load, temperatures, etc). The communication protocol is obviously more complex, but once you've learned it you'll never look back at standard hobby servos. Each individual servo comes with two brackets, but you can also buy 100+ brackets for about $100, which are stronger than the aluminum Lynxmotion SES, and about 1/10th of the cost. For a controller if you don't want to build your own, a CM-5 runs around $70ish and is fully programmable in C. If you want to build your own its a simple matter of plugging in the TX/RX of a UART from an AVR into the serial bus, and programing away.

Just something to consider, you don't have to make that $870 investment of a Bioloid Comprehensive Kit to get started using these servos, they really are a fantastic piece of technology.


I would modify this slightly to say "But get the best for your application, even if it stretches you a bit."

People make a really big mistake by choosing servos by price alone, even if they do have specifications that match a given application. There is a lot of truth in the saying "you get what you pay for" with respect to electronic components and devices. From now on, for projects I plan to keep together, my base line servo is going to be the Hitec HS-645MG because it has a good torque, as well as a metal gear train. Yes, these are a stretch for me to get in any quantity due to the higher price, so I will be getting them 6 or 12 at a time, as I can get the money together for them, because I know they will be used in projects I build. I already need a few more of these for the new arm on W.A.L.T.E.R.

In fact, the HS-645MG (analog) servo is almost identical to the HS-5645MG (digital) servo. The only difference is the electronics board!

8-Dale

Adrenalynn
12-20-2008, 01:15 PM
I'll also note that not _all_ the HS-645MG's gears are metal. Some are metalicized plastic.

LinuxGuy
12-20-2008, 02:30 PM
I'll chime in here even though its off-topic a bit...

The AX-12 is hands down the best bang for buck of any servo on the market. Double the torque of an HS-645 and its only $45. Fully digital, serial daisy chained, and every type of feedback you could want (positional, current load, temperatures, etc). The communication protocol is obviously more complex, but once you've learned it you'll never look back at standard hobby servos.
Oh, I haven't forgotten about the AX-12. In fact, these are on my list of things I really want to tinker with at some point. I wish there were SES compatible brackets to allow attaching other SES components to. These brackets would not be difficult to design. Maybe I will get into the drawings and see what I can come up with. Unfortunately, I don't have any means to fabricate my designs. I definitely have places I could use the AX-12, especially in heavy lifting joints of arms and legs.

I'm heavily into software development mode right now, and am writing libraries for the Arduino. Perhaps the AX-12 could be used on a Phoenix style hexapod for the hip vertical joint where it has to lift the whole leg and support the entire robot.

8-Dale

DresnerRobotics
12-20-2008, 05:47 PM
Well personally I wouldnt want a mixed servo robot, either all AX-12s, or all PWM servos. Don't really need to fab your own brackets with as strong as the stock bioloid ones are, and there is enough variety there to fill just about ever niche.


Oh, I haven't forgotten about the AX-12. In fact, these are on my list of things I really want to tinker with at some point. I wish there were SES compatible brackets to allow attaching other SES components to. These brackets would not be difficult to design. Maybe I will get into the drawings and see what I can come up with. Unfortunately, I don't have any means to fabricate my designs. I definitely have places I could use the AX-12, especially in heavy lifting joints of arms and legs.

I'm heavily into software development mode right now, and am writing libraries for the Arduino. Perhaps the AX-12 could be used on a Phoenix style hexapod for the hip vertical joint where it has to lift the whole leg and support the entire robot.

8-Dale

Zenta
12-21-2008, 12:22 AM
The AX-12 is hands down the best bang for buck of any servo on the market. Double the torque of an HS-645 and its only $45.
If you are thinking of holding torque, I agree that AX-12 are much better than HS-645MG. But when it comes to running/load torque I can't agree that the AX-12 are better at all. I postet my findings in the ultimate bioloid thread (http://forums.trossenrobotics.com/showthread.php?t=1437&page=17). I'm not saying this because I'm against using the AX-12 but I think everyone should be aware of the big difference in hold vs. load torque.

DresnerRobotics
12-21-2008, 12:50 AM
Yes, I was referring to holding torque, as that is what most servos are measured at by the manufacturer. Did you ever test out the 645s and 5645s on their moving torque? I'd be curious to see how they come out.

Zenta
12-22-2008, 06:41 AM
Yes, I was referring to holding torque, as that is what most servos are measured at by the manufacturer. Did you ever test out the 645s and 5645s on their moving torque? I'd be curious to see how they come out.
Yes I did some tests on the 645 and if I remember correctly it was about 8 kg moving torque. A more thorough test should be taken to verify my findings about the 645 though.. I didn't test the 5645.

CyPrD
12-25-2008, 03:43 PM
Hi guys,

hope ya'll have (had) great Xmas and all the best to upcoming year :-)
J.

Zenta
01-14-2009, 02:53 PM
Hi,

For information I've just uploaded a little tutorial of how I did the hardware modifications on the Futaba T7C 2,4 GHz RC transmitter for controlling Phoenix. You'll find it in the Data Center section (http://forums.trossenrobotics.com/downloads.php?do=file&id=137).

-Zenta

MA_BLACK
12-22-2010, 06:34 PM
Hello, I am working with PEP of Zenta, and I am understanding and controlling the formulas for IK legs, but I do not understand how to calculate page 1 (Body & Coxa), where are the formulas, where I can see, for able to walk the hexapod and enable it to rotate. I want to know how to calculate the IK.

Thanks
Greetings

MA_BLACK
12-24-2010, 02:51 AM
I need help with motion sequences, the following code for the microcontroller, as defined by the movement, these numbers are loaded into the variables?

if (GaitType == 0){ //Ripple Gait 6 steps
LRGaitLegNr = 1;
RFGaitLegNr = 2;
LMGaitLegNr = 3;
RRGaitLegNr = 4;
LFGaitLegNr = 5;
RMGaitLegNr = 6;

NrLiftedPos = 1;
TLDivFactor = 4;
StepsInGait = 6;
NomGaitSpeed = 150;
}

What I'm trying to do is change the code to control a robot with 4 legs, someone can lend a hand, or know if you can.

Thanks