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Droid Works
06-24-2008, 08:28 PM
Is the Bioloid Assembled IMU (http://www.trossenrobotics.com/huv-robotics-bioloid-assembled-imu.aspx) plug and play? I couldn't find any detailed instructions so I am not sure what is involved in setting it up. There is info on installing it in the chest and the specs on it but no info on software setup. I just ordered one and should have it in a few days so any info would be appreciated.

JonHylands
06-24-2008, 09:07 PM
Is the Bioloid Assembled IMU (http://www.trossenrobotics.com/huv-robotics-bioloid-assembled-imu.aspx) plug and play? I couldn't find any detailed instructions so I am not sure what is involved in setting it up. There is info on installing it in the chest and the specs on it but no info on software setup. I just ordered one and should have it in a few days so any info would be appreciated.

Yes, it is plug and play. It, like my other Bioloid devices, plugs into the bus, and acts like any other device on the bus. The reason there is no info on software setup is because there isn't any :-)

I would strongly suggest you read the AX-12 manual carefully - there is a wealth of information in there that describes how to talk to bus devices, and the IMU works exactly the same way.

Please let me know if you have any other questions...

- Jon

tom_chang79
06-24-2008, 11:37 PM
Check out this video of StuartL on this thread:

http://robosavvy.com/forum/viewtopic.php?t=2645

Quite impressive use of Jon's IMU...

Droid Works
06-25-2008, 01:23 AM
Yes, it is plug and play. It, like my other Bioloid devices, plugs into the bus, and acts like any other device on the bus. The reason there is no info on software setup is because there isn't any :-)

I would strongly suggest you read the AX-12 manual carefully - there is a wealth of information in there that describes how to talk to bus devices, and the IMU works exactly the same way.

Please let me know if you have any other questions...

- Jon

Awesome! I was hoping that was the case. Happy happy joy joy!

Droid Works
06-25-2008, 01:26 AM
Check out this video of StuartL on this thread:

http://robosavvy.com/forum/viewtopic.php?t=2645

Quite impressive use of Jon's IMU...

Very cool the first video he had slow response and unstable behavior. But the second video was perfect. He seemed to get all the setting right. Very cool, cant wait to get mine in the mail.

Droid Works
06-27-2008, 01:45 PM
Is there a way I can see the real time data on the accelerometer so I can get it set exactly how I want it? Or can you tell me what your settings are or a screen shot. So I don't have to go threw the trial and error portion of setting the gyro.

JonHylands
06-27-2008, 01:53 PM
The internal control table registers on the IMU (all six sensors) are updated 100 times per second. You can retrieve the data from them as fast as you want, but it won't change any faster than 100 Hz.

Droid Works
06-27-2008, 11:03 PM
Basically what I want to do is set the knee, foot and ankle servos at different speeds and compensation levels. I found this method works best with my other humanoids. Is this possible with the IMU and how do you do it?

openmindedjjj
06-28-2008, 02:35 AM
thats a good qustion i just bought a boiloid robot and i was thinking about doin the same.
you could call trossen robotics if nobody can answer your qustion on here.
on the top of this page there is a contact button you can click on.
but you should get all the info when you get your imu.. when i gets delivered to your house there should be a book or some kind of instructional manual or something inside other than just the imu. by the way do you know if the imu is better than the krg-3 gyro.. i wana get a gyro but im not shure which is better... the imu or the krg-3 gyro

JonHylands
06-28-2008, 07:12 AM
Basically what I want to do is set the knee, foot and ankle servos at different speeds and compensation levels. I found this method works best with my other humanoids. Is this possible with the IMU and how do you do it?

Its not really possible to do that directly with this IMU as you do with the ones on your other humanoids, at least not directly. They use servos that are controlled with what amounts to an analog signal, and its very easy mechanically to convert a gyro's signal to a delta to mix with a servo signal.

You can do the same thing with the Bioloid IMU, but it will require some clever programming, and filtering.

The IMU doesn't come with any paper documentation - the documentation is on the website referenced from the product pages. I don't explain how to use the IMU to help a humanoid balance in the documentation for the simple reason that I don't know.

Droid Works
06-28-2008, 02:14 PM
The IMU doesn't come with any paper documentation - the documentation is on the website referenced from the product pages. I don't explain how to use the IMU to help a humanoid balance in the documentation for the simple reason that I don't know.


Huhh?? I wish I knew that before I bought it. So we are pretty much on our own to figure out how and if it works. I have been messing with it for a day and a half now and I cant get it to do anything yet. Is there anyone out there that has some code or advice on getting this to work?

JonHylands
06-28-2008, 02:56 PM
What do you mean, you can't get it to do anything? Does the red light turn on for 1/2 second when you power it up? Have you tried getting values from it? I know you can retrieve values from it using the default Bioloid software, because I know a couple people who have done that. One of them, srobot, is a member of this community, and I'm sure he would be willing to help you out. If you need help getting in touch with him, let me know.

- Jon

Droid Works
06-28-2008, 03:00 PM
What do you mean, you can't get it to do anything? Does the red light turn on for 1/2 second when you power it up? Have you tried getting values from it? I know you can retrieve values from it using the default Bioloid software, because I know a couple people who have done that. One of them, srobot, is a member of this community, and I'm sure he would be willing to help you out. If you need help getting in touch with him, let me know.

- Jon

The light turns on, I can get the values but I can not find any way to make it work for balance.

JonHylands
06-28-2008, 06:04 PM
Well, its a non-trivial thing, for sure. StuartL has one, and he is using it successfully for balance, but he's doing his own motion code.

Did you buy it directly from me, or from Trossen? If you bought it from Trossen, see if they'll take it back. If they won't, I'll buy it from you for what you paid for it, if you're not satisfied with it...

- Jon

Droid Works
06-28-2008, 07:49 PM
I don't want to get rid of it I just want to get it working. I program in VB and have only a basic understanding of C. I just need the code or some detailed instruction on how to get it working.

srobot
06-28-2008, 09:52 PM
I don't want to get rid of it I just want to get it working. I program in VB and have only a basic understanding of C. I just need the code or some detailed instruction on how to get it working.

I don't think you can program the Bioloid in VB (Visual Basic). You could write a VB - C converter type software then send it to the robot. But you would still need C knowledge, but maybe if you ask nicely : )...

trey3670
06-28-2008, 10:50 PM
ok I am following,but getting lost here,I had considered buying a gyro for the bio also.
here is what I am getting,
that the gyro in question goes into the bioloid system just like another ax-12 and in order to use this you need to write your own bcp? like the balancing foot act,you need to incorporate the readings from this gyro into that? or do you need to get more involved into programing? basicly can you use it with the software provided by robotis? I have been meaning to ask these questions just havent got around to it. thanks guys

DrWass2
06-29-2008, 12:49 AM
Have you tried standing still and having somebody push you around with your feet stuck to the floor. There is a limit before you must use your arms for balance or have to move a foot before you fall over.
Maybe you can program in some arm balancing motion, as a means of moving the COG to keep it over the feet. I think you need to include more then just the ankles and knees. just an Idea from a newbee who just ordered a comprehensive kit....keep up the good work. I think this got on the wrong thread.....never mind!

Droid Works
06-29-2008, 01:28 AM
ok I am following,but getting lost here,I had considered buying a gyro for the bio also.
here is what I am getting,
that the gyro in question goes into the bioloid system just like another ax-12 and in order to use this you need to write your own bcp? Yes

like the balancing foot act,you need to incorporate the readings from this gyro into that? or do you need to get more involved into programing? Yes you have to write your own Program in C

basicly can you use it with the software provided by robotis? No

I have been meaning to ask these questions just havent got around to it. thanks guys

This is the problem I am having I dont know enough C to do it. I use VB but you cant use VB with it.

Adrenalynn
06-29-2008, 02:39 AM
If you prototyped something in VB, keeping an eye towards portability, I'm sure someone here would port it to C...

Droid Works
06-29-2008, 06:25 AM
I think I am going to go to the book store today and get a book on C. I should have a better understanding of it anyways. When I get the IMU working I will post the code in the download section unless someone beats me to it...lol

JonHylands
06-29-2008, 07:24 AM
basicly can you use it with the software provided by robotis?

You can, but, like everything else, there are caveats. The software provided by robotis allows you to query arbitrary bus devices. It is very difficult to use the IMU with the standard walk sequences, because you can't incorporate feedback into them while they are moving. If you are running your own walk sequencer, then its certainly doable.

Droidworks (and anyone else that cares to comment):

Do you think that the product blurb for the IMU is misleading? Is there something I should add to make this kind of point clearer? I don't want people buying my products and then feeling like they have been misled, especially when they spend $250 on it.

- Jon

srobot
06-29-2008, 02:33 PM
Droidworks (and anyone else that cares to comment):

Do you think that the product blurb for the IMU is misleading? Is there something I should add to make this kind of point clearer? I don't want people buying my products and then feeling like they have been misled, especially when they spend $250 on it.

- Jon

It is what I thought it was going to come as.

[deleted by Alex, per Matt]



ok I am following,but getting lost here,I had considered buying a gyro for the bio also.
here is what I am getting,
that the gyro in question goes into the bioloid system just like another ax-12 and in order to use this you need to write your own bcp? like the balancing foot act,you need to incorporate the readings from this gyro into that? or do you need to get more involved into programing? basicly can you use it with the software provided by robotis? I have been meaning to ask these questions just havent got around to it. thanks guys

As far as I know, the only humanoid robot to have plug 'n play gyros (in line with the servos) is the KHR-1.

For the cartwheel code (which took me over 40 hours to write) I used the BCP (Behavior Control Programmer) what I did was call up pages from the Motion Editor, and at a few spots check if the cartwheel was still on track using the values from the IMU. If the robot was falling to the left he'd shift his weight to the right a little by calling up the page I made if that were to happen.

I hope that makes sense.

Cheers,
--Scotty

tom_chang79
06-29-2008, 05:44 PM
I am interested in programming the Bioloid in C as well. I've looked around on Jon's Bioloid Wiki and the tutorial section at Robosavvy, but still quite puzzled at the how to program it in C in particular with the Bioloid setup.

I believe from what I've read so far, you need to use GNU GCC and a library that supports the Atmega 128 MCU... Also, I believe there are libraries specifically written for the CM-5, AX-12+, and etc...

Is there a complete "howto" document anywhere that have full support of links to source codes and the flashing aspect?

tom_chang79
06-29-2008, 05:46 PM
Is there a complete "howto" document anywhere that have full support of links to source codes and the flashing aspect?

I'm trying to bring it back... :tongue:

Adrenalynn
06-29-2008, 05:50 PM
And doing a darned good job of it.

I do a lot of stuff on the AVR chips, and use AVR-GCC all the time. The bestest site on the 'Net for AVR help is http://www.avrfreaks.net. I haven't played with Jon's board, but if one wants to learn C from an old-skool ground-up sorta perspective, there's worse places to start than the AVR processors and AVR-GCC!

http://www.avrfreaks.net/index.php?module=FreaksTools&func=viewItem&item_id=376

It's not free, but there is a pretty decent looking BASIC compiler for the AVR, btw. It's called FastAVR.

Droid Works
06-29-2008, 06:51 PM
You can, but, like everything else, there are caveats. The software provided by robotis allows you to query arbitrary bus devices. It is very difficult to use the IMU with the standard walk sequences, because you can't incorporate feedback into them while they are moving. If you are running your own walk sequencer, then its certainly doable.

Droidworks (and anyone else that cares to comment):

Do you think that the product blurb for the IMU is misleading? Is there something I should add to make this kind of point clearer? I don't want people buying my products and then feeling like they have been misled, especially when they spend $250 on it.

- Jon

I would put a blurb on it explaining that it is not like most humanoid gyro kits. For example on the kondo robots I just plug in the gyro and adjust it with the provided software and my bot it up and balancing in 5 min. For the IMU you have to write your own C code. Dont get me wrong, this is a great product but there is ALLOT involved in getting it to work.

srobot
06-29-2008, 08:24 PM
I would put a blurb on it explaining that it is not like most humanoid gyro kits. For example on the kondo robots I just plug in the gyro and adjust it with the provided software and my bot it up and balancing in 5 min. For the IMU you have to write your own C code. Dont get me wrong, this is a great product but there is ALLOT involved in getting it to work.

To use the IMU you do not have to program in "C", I explaned earlyer in this post one way to do it with the BCP (ask me any questions you may have about it).

You have a KHR-1, correct? From what I remember Lem saying way back, this is the only humanoid (that is sold big time) that does not need code to use a gyro. With that kit you simply use a R/C gyro in line with the leg servos, but from what I remember the RN-1, KHR-2, and KHR-1HV all need to use the gyro as a sensor in the code, just like an ultrasonic sensor.

An IMU is not exactly a gyro, a gyro senses 2 or 3 axis, but a IMU senses 6 axis.

I just don't think the description should include information that is incorrect is all.

I find it more fun writing my own programs, over using other people's code.

Well, back to programming!

Droid Works
06-29-2008, 08:30 PM
There is no coding needed for the kondo bots its all done in the gui.You do have to write in C to get the IMU to work as a balance gyro. If you know of a way to get arround that we are all ears.

Alex
06-29-2008, 08:34 PM
I'd love to see any code that people are working on to get this working. I love looking through C code (great way for me to learn it) and need to add one of these IMU's to our Bioloid for Chibotica:D

srobot
06-29-2008, 09:20 PM
There is no coding needed for the kondo bots its all done in the gui.You do have to write in C to get the IMU to work as a balance gyro. If you know of a way to get arround that we are all ears.

What are you referring to as "the gui"?

I can not show people (except my sponsors) my full code in BCP and ME and what is does until after Fall Chibotica 2008 (oops! did I say what I'm doing for chibotica?! :o).

So check back on the forums after the event (October 18 & 19 2008) or come to the event and I will give you all/most of my code and show you what it does.



I'd love to see any code that people are working on to get this working. I love looking through C code (great way for me to learn it) and need to add one of these IMU's to our Bioloid for Chibotica:D

You wish... little cheaters... :cool:

But yeah, I love to learn that way too. In fact, most of what I know I got that way.

--Scotty

srobot
06-29-2008, 09:23 PM
"In the basic CD, the Behavior Control Programmer, Motion Editor, and Robot Terminal are provided; the expansion CD provides a GCC compiler for C programs, a development environment, and a library, as well as various Window libraries and example sources are provided for users to control Dynamixel and Bioloid robots via PC." ~ Bioloid Expert Manuel

Alex can you sell me the expansion CD-ROM? If so, please PM me.

srobot
06-29-2008, 09:50 PM
Droid how's the programming coming?

Alex
06-29-2008, 10:29 PM
You wish... little cheaters... :cool:

But yeah, I love to learn that way too. In fact, most of what I know I got that way. haha, allright, you caught me:p

I hope that I'll get some time between now and Chibotica to mod out my Bioloid.

Seriously though, Droid, keep us posted with your work:D

tom_chang79
06-29-2008, 11:31 PM
Well, I believe that the IMU really isn't a plug-and-play kind of device for the Bioloid strictly because of the architecture of the way Dynamixels are...

Dynamixels uses packet communication via 1 wire serial (2 if you count common/gnd). Therefore, the servo motions aren't control through PWM, which can be mixed real easily.

"Mixing" of the IMU's data and the actuator control would have to be done somewhat in the software domain. You'd have to alter the servo position (0 to 1023) via logic.

I think (correct me if I'm wrong, Bioloid owners), that the offsets are stored in page 0 of the motion control. If there was a way to alter the values on page 0 in realtime, perhaps other motion pages do not have to be altered, since the offset page/trim would be added/subtracted from the values of actuators on other pages... Altering these values in software based on the readings from the IMU, hmmm would probably get you as close to a "kondo gyro in a kondo bot" type of hook-up...

Just a thought...

Adrenalynn
06-29-2008, 11:33 PM
If you need a "pretty good" C programmer to help you out Alex, I suddenly find myself interested. Where "pretty good" is defined as "I still have my First Edition K&R C Programmers Reference autographed/dated for me by both Kernighan and Ritchey in 1979"... ;)

Adrenalynn
06-30-2008, 12:05 AM
[edit] Think I'll reserve this one for Droid' or Alex...

tom_chang79
06-30-2008, 12:36 AM
This is one of my favorite reference book on C:

Amazon.com: The Waite Group's New C Primer Plus (The Waite Group): Mitchell Waite, Stephen Prata: Books

http://ecx.images-amazon.com/images/I/719V7YMSF9L._SL500_AA240_.gif

I couldn't believe they still sell this book (even though used). It starts at $0.01, can't go wrong with that :tongue:

I'm not as veteran as Adrenalynn here, but I have been programming in C since 1989, because of this, I consider C++ to be an "overglorified C" :P

Droid Works
06-30-2008, 01:34 AM
What are you referring to as "the gui"? Graphical user interface/ H2H Software

I can not show people (except my sponsors) my full code in BCP and ME and what is does until after Fall Chibotica 2008 (oops! did I say what I'm doing for chibotica?! :o). OK?

So check back on the forums after the event (October 18 & 19 2008) or come to the event and I will give you all/most of my code and show you what it does.



You wish... little cheaters... :cool:

But yeah, I love to learn that way too. In fact, most of what I know I got that way.

--Scotty
Anyways, Its going to be a while but I will start studying C and work on the code. So if anyone else is working on it I will be more than happy to share info. I am going to try to make a program in VB after I finish the code to install the C code and give you a GUI to adjust your leg settings much like in H2H.The exe file will take some time to make but I will share the C code as soon as its done with anyone who wants it. I will be in the trossen downloads section when I am done.

JonHylands
06-30-2008, 07:31 AM
I think (correct me if I'm wrong, Bioloid owners), that the offsets are stored in page 0 of the motion control. If there was a way to alter the values on page 0 in realtime, perhaps other motion pages do not have to be altered, since the offset page/trim would be added/subtracted from the values of actuators on other pages... Altering these values in software based on the readings from the IMU, hmmm would probably get you as close to a "kondo gyro in a kondo bot" type of hook-up...

Just a thought...

Tom,

Nice idea, but unfortunately this would affect all of the servos, and not just the ankle/hip ones you want to adjust...

- Jon

tom_chang79
06-30-2008, 09:30 AM
Well, what I was implying was just to alter the servos of interest for balancing, perhaps just the servos that effects the legs, possibly the arms for counter balancing... The trim of other servos that are independent of the balancing should be left as is... Just a thought...

Alex
06-30-2008, 09:50 AM
[edit] Think I'll reserve this one for Droid' or Alex...

?


This is one of my favorite reference book on C:

http://www.amazon.com/Waite-Groups-P...4804129&sr=8-2 (http://www.amazon.com/Waite-Groups-Primer-Plus-Group/dp/0672303191/ref=sr_1_2?ie=UTF8&s=books&qid=1214804129&sr=8-2)

Thanks for the book recommendation Tom! I'll have to check that out. In the meantime, I started a C Programming Recommendations thread (http://forums.trossenrobotics.com/showthread.php?t=1957) for this conversation to continue:D

Alex
06-30-2008, 10:47 AM
per Matt, I'm deleting all of the posts that involved the fighting.

Adrenalynn
07-01-2008, 03:40 AM
And if you do, you'll likely talk to Alex who posted right above you... :)

Droid Works
07-14-2008, 09:06 PM
Ok, I learned C and I spent many hours trying to get the IMU to work like a gyro in any other bot and its a no go. The only thing you can do is get it to work while the robot is standing still. You cant get it to work while running a motion like walking. The bioloid servos are networked and cant run 2 codes at once thus no gyro while walking. I see no way possible to make this work for walking stabilization. If anyone can prove me wrong I would be very happy, but I don't think that will happen. I guess I will try to find another use for it.

DresnerRobotics
07-15-2008, 12:15 AM
Ok, I learned C and I spent many hours trying to get the IMU to work like a gyro in any other bot and its a no go. The only thing you can do is get it to work while the robot is standing still. You cant get it to work while running a motion like walking. The bioloid servos are networked and cant run 2 codes at once thus no gyro while walking. I see no way possible to make this work for walking stabilization. If anyone can prove me wrong I would be very happy, but I don't think that will happen. I guess I will try to find another use for it.

I think you're going about it wrong... did you write your own walking gait in C?

In order to make it work while walking, you'll need to essentially write your own walking gait/control interface in C that reacts dynamically based upon the input from the IMU. I'm vastly over simplifying it, but I haven't worked it out entirely myself.

tom_chang79
07-15-2008, 02:28 AM
Didn't StuartL at robosavvy used it successfully to implement an IK-driven stabilization scheme for his Bioloid? Might be worthwhile to shoot him a PM or something there and ask for his help...

Tyberius is right, I think you'll need to make some dynamic walking algorithm (IK-based) and wrap the code with some interrupts to make it work like you'd want it to do... With the Bioloid, you're essentially "mixing" the position (PWM for regular servos) in software, so you probably have to have an interrupt-driven "mixing" function in there somehow. Of course, this sounds easy at the high level, implementation is another matter... ;P

A-Bot
07-15-2008, 07:45 AM
I think it would be better to describe the IMU as an AX-12+ Network IMU instead of a Bioloid IMU. I'm going to buy the IMU when I get further along with my project, but I'm not using the CM-5, and I fully understand that what it does is provide digital readings of the 6 parameters.

JonHylands
07-15-2008, 08:21 AM
Its called the Bioloid IMU because it runs off of the Bioloid bus. It really has nothing to do with the AX-12, other than being a Bioloid bus device (like an AX-12 is). You can use it to modify values that you send to an AX-12, but that's certainly not required.

A-Bot
07-15-2008, 08:33 AM
Its called the Bioloid IMU because it runs off of the Bioloid bus. It really has nothing to do with the AX-12, other than being a Bioloid bus device (like an AX-12 is). You can use it to modify values that you send to an AX-12, but that's certainly not required.

I understand that, I just think in different terminology.

PS. My IO board is in the mail. :D

ScuD
07-15-2008, 09:05 AM
Regarding the IMU, what's the advantage of the Gyro in combination with the accelerometers as opposed to just accelerometers? Does the gyro have faster/more accurate readings?
Or are the accelerometers used in conjunction with the gyro as a kind of "calibration" to interpret the gyro signals when used under a certain angle?

Haven't ever used any of these items so I'm a bit in the dark here..

JonHylands
07-15-2008, 09:22 AM
A gyro measures the rate of rotation of the sensor. An accelerometer measures linear acceleration. Accelerometers can be used to measure tilt (if the sensor isn't moving), since gravity is a force of acceleration.

Typically, in an IMU, you use the gyros to measure rotation (i.e., falling), but gyros drift very quickly, so you need to periodically (or continuously) calibrate them using the accelerometers. An extended Kalman filter does this automatically.

Go to google and type in:

gyro drift kalman

to get more information than you can shake a really big stick at.

Droid Works
07-15-2008, 10:31 AM
Didn't StuartL at robosavvy used it successfully to implement an IK-driven stabilization scheme for his Bioloid? Might be worthwhile to shoot him a PM or something there and ask for his help...

Tyberius is right, I think you'll need to make some dynamic walking algorithm (IK-based) and wrap the code with some interrupts to make it work like you'd want it to do... With the Bioloid, you're essentially "mixing" the position (PWM for regular servos) in software, so you probably have to have an interrupt-driven "mixing" function in there somehow. Of course, this sounds easy at the high level, implementation is another matter... ;P

Yes I have seen his video and read some of his code. It is just lean forward and back. I have tried approaching it from every angle new walking gait ect and it just isn't possible. If anyone can make it work while a it is walking I would love to see it. There is no way that I can see to get control over the knee, ankle and leg servos while running any kind of gait that I can see. In order for it to work as a stabilization gyro you have to have control over those servos while running the gait. I hope I am wrong and would love to see someone get it to work, but it is either beyond me or not possible.

DresnerRobotics
07-15-2008, 11:01 AM
Yes I have seen his video and read some of his code. It is just lean forward and back. I have tried approaching it from every angle new walking gait ect and it just isn't possible. If anyone can make it work while a it is walking I would love to see it. There is no way that I can see to get control over the knee, ankle and leg servos while running any kind of gait that I can see. In order for it to work as a stabilization gyro you have to have control over those servos while running the gait. I hope I am wrong and would love to see someone get it to work, but it is either beyond me or not possible.


Again, I think you're looking at the problem incorrectly. The problem isnt that you need to modify the existing gaits using the IMU... you need to build a walking gait from the ground up using the IMU to dynamically adjust the COG. Integration with the IMU input should be implemented from the get go, not as an after thought.

Did you write your own gait in C? That's where you need to start. Once you have a solid grasp of how to write a walking gait from scratch, look back at integrating the input from the IMU into it and start over.

JonHylands
07-15-2008, 11:18 AM
When you build your own gait, you have full control over all the servos all the time. So, you can take the value of the ankle servo from the walk sequence, and adjust what you're passing to the servo by a small amount as dictated from the IMU.

ScuD
07-15-2008, 12:00 PM
concerning building walking gaits in C, do you use lookup tables, IK or another method?

JonHylands
07-15-2008, 12:03 PM
I use pre-built sequences, made by interpolating between static poses.

ScuD
07-15-2008, 12:10 PM
Basically you move the servo's from one position to the next, and have the bot interpolate a path between those two positions? Is the interpolation done by the hammer or an off-board pc?

/edit; should've read better, missed the pre-built part

JonHylands
07-15-2008, 12:23 PM
Yes, the interpolation is done by my PC. The code running on the Hammer (which is the same code as I run on my PC) can do the interpolation as well, but its too slow to do it in real time.

Droid Works
07-15-2008, 05:16 PM
Again, I think you're looking at the problem incorrectly. The problem isnt that you need to modify the existing gaits using the IMU... you need to build a walking gait from the ground up using the IMU to dynamically adjust the COG. Integration with the IMU input should be implemented from the get go, not as an after thought.

Did you write your own gait in C? That's where you need to start. Once you have a solid grasp of how to write a walking gait from scratch, look back at integrating the input from the IMU into it and start over.
I know exactly what you are saying, I don't think I am expressing my self fully. Yes I did write a gait from scratch and it is not possible, and even if it were that is a HUGE task to write every motion and gait from scratch just to get it to work. Like I said I don't see any reasonable way to get this to work. If any one else can more power to you but I put enough unfruitful hours into this thing and I gave it my best shot with no success. So please if any of you would like to continue working on it be my guest. I would love to see this thing work but I don't have months to put into this thing and thats what it will take.

JonHylands
07-15-2008, 06:40 PM
Well, like I said DroidWorks, I will offer you full money-back if you want to return it...

Droid Works
07-15-2008, 08:07 PM
Well, like I said DroidWorks, I will offer you full money-back if you want to return it... Thank you that is very nice of you. I should have researched it allot better than I did. Not that it isn't a great product but it is just I'm not sure I have the time or skill to get it to work. Send me a pm with the shipping info to send it back. Thanks again:)