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ooops
07-15-2008, 05:02 PM
OK, as most of you know by now I am just getting started with bots. I really like the idea of the Mech Wars. It provides me with a goal and a dead line and an excuse to go across the country next June (like I don't do that a few times a year anyway).
So, I am looking at a couple of kits to get me started and although I plan to do a bit more research on my own, thought I would toss the question out there ... which kit is the better to start with?
I am looking at the Bioloid and the biped Scout. Have I missed anything?
I like the Scout and the servo erector set with the HS-5645 servos and am leaning that way.
Since time is critical I would like to start with a kit ... no time to re-invent the wheel.
Since weight is a critical issue ... I will need strong servos.
Since all the details are not nailed down ... flexibility in design will be critical.
All suggestions and opinions are appreciated!
Ed

lamont
07-16-2008, 04:27 PM
I have the bioloid kit, and I'm quite happy with it. The main feature that drove me to it was the ability to get feedback from the servos. Also, the daisy-chain wiring scheme will simplify the wiring greatly.

While I have not actually built a walker of any type, I have to imagine that trying to walk without position and torque feedback would be like climbing stairs numbed from the neck down. The HS-5645 don't appear to have any feedback at all.

DresnerRobotics
07-16-2008, 04:38 PM
Unfortunately if you're going with a Lynxmotion SES based system, the SES alone is pretty heavy. I believe the scout has a hard enough time walking with just a battery as payload using 5645's, let alone once you add a camera and weapons.

Any 'hitec type' servo based 5dof+ walker is probably going to have to be running 5990TGs to be effective.

ScuD
07-16-2008, 04:59 PM
I don't own any kits but my own made bots, but I can definately advise the Bioloid kit.
Seems to put a tick at every point on your list.

ooops
07-16-2008, 05:01 PM
Thank you guys ... just the info I needed!
Sounds like I am leaning toward the Bioloid kit.
All suggestions are welcomed! Keep them coming.

DresnerRobotics
07-16-2008, 05:15 PM
One thing to note with the Bioloid system is that you will most likely not be able to use the stock software for a competition like Mech Wars very effectively. It's possible, but will be pretty limited.

You can reflash the CM-5 though and/or program it directly in C, or look at different controllers entirely.

ooops
07-16-2008, 05:24 PM
Well, I am almost afraid to ask, is there a kit out there that would be "easy" to adapt.
I fully expect to make compromises on some issues, but with the learning curve being more vertical than steep, any time saved in one area is time gained for other areas. Ultimately, I would like to just be far enough along to know that my Mech isn't going to just stand still and be a target the first year and then see what works. Year 2 on the other hand I expect to dominate! As you can see I have a patient plan for world domination.

DresnerRobotics
07-16-2008, 05:40 PM
I would wager that more important than the kit, is a solid grasp of an applicable programming language. If I had to pick an 'easy kit' it would probably be a scout based on the Basic Atom, if only because that language is very easy to learn.

LoDebar
07-16-2008, 10:28 PM
I have only played with a couple bioloid servos so I don't have any direct experience with the kit so I can't really comment on them.

I have build two bi-peds using the Lynxmotion SES, the Lynx 209 and Bi-ped Pete robots (I am the one that did the original robots for them). I was able to get them to walk with the HS-5645 servos, and I would have to say they are the minimum that will need. I am going to try to get mine to work for this event so I can see how much payload I can get on them.

If you have a little extra money get the higher torque servos. When it is all said and done, the more power you have, the happier you will be.

The one thing I do know, teaching a robot to walk does take a lot of time. Kind of like teaching a baby how to walk. It doesn't happen overnight.

Another thing to look at is the RoboNova kit. It has a lot of built in walking routines, and I am pretty sure it can handle this event. I am going to see if mine can.

With enough motivation, I might show up with an army of robots to this event.

Pete

sam
07-17-2008, 02:31 PM
Ok, so I haven't tried the bioloid but I will tell you what I think about the lyxmotion SES.

I have only used low end-servos (that means no feedback wahtsoever :genmad: you pay for what you get :rolleyes: ) It was pretty easy to learn. But then again, I only had programed routines, nothing that can adjust itself whilst walking. So I didn't do any heavy programing to get it there. I think the biggest thing you are going to face for this event is the programing. And you're better off to learn to program than to pay someone to do it.

Even if it's simple routines with the lynxmotion Scout (you can put a Basic Atom and make routines so that when you put the analog stick on a PS2 controller the bot uses the command to go fowardand the 'X' is for shooting. I think you could get by with this.

Sam

Adrenalynn
07-17-2008, 03:09 PM
You'd need to come up with a plan to make that wireless...

sam
07-17-2008, 03:13 PM
Madcatz style wireless PS2 controller. There are a lot of Tutorails on the Lynxmotion site for wireless Ps2 controllers.

LoDebar
07-17-2008, 11:58 PM
Why do you need feedback from the servos? Model airplanes do a amazing things without servo feedback.

But then again, you can't beat the human eye for real time feedback control.

Thing to keep in mind about all these cheap wireless controllers. They are not designed to operate in an environment where there are a lot of other devices transmitting. The last thing you want to do is go to a tournament and findout that you can't control your robot like you did at home because of all of the frequency interference.

Pete

DresnerRobotics
07-18-2008, 12:04 AM
Thing to keep in mind about all these cheap wireless controllers. They are not designed to operate in an environment where there are a lot of other devices transmitting. The last thing you want to do is go to a tournament and findout that you can't control your robot like you did at home because of all of the frequency interference.



This is excellent advice. Robogames has a lot of things going on, your best bet is to use secured channels such as wifi IP devices, zigbees, etc. Who knows what channel those 2.4ghz wireless PS2 controllers use, but I can almost guarantee you'll run into interference with them.

Personally I'm using the private wifi network I'll have established for the wifi IP cameras and PCs there.

ooops
07-18-2008, 07:51 AM
Bioloid on it's way!
Gotta start somewhere - the deep end is as good a place as any!

sam
07-18-2008, 08:18 AM
Hehehe. You'll tell us waht you think abut it! :happy:

For the contoller It's true that I will probably loose my connectin in an invirement like this one.

It depends on how much time I gave t prepare fr the games but I might just try autonmous.

tom_chang79
07-22-2008, 02:57 PM
Another Bioloid owner! Hooray! :D

The Bioloid kit is the best value of all the kit bots out there... You get smart actuators, with gobs of torque (200+ oz-in) and a bracket-based system that allows you to place two DOFs on the same axis (hip and ankle for example)...

Pics, pics, pics!!!

ooops
07-22-2008, 10:21 PM
Another Bioloid owner! Hooray! :D
Got it today! With much glee and anticipation we (my 12yo and I) commenced building the Gerwalk, seemed a quick and easy build. We had it assembled in just a couple of hours. Truly a great system! All was great with the world until we realized that the laptop designated to robot work doesn't have a RS232 port:(
So tomorrow I will be ordering the USB adapter, a JIS screwdriver set, and maybe a couple other goodies.
Pics taken ... try and post tomorrow.

sam
07-23-2008, 09:59 AM
That's my problem with all my computers taht try to connect robots. And my USB to Serail converters work for only some time and then stops working... It's really a bummer. I didn't know that the bioloid work with a serial port.

Adrenalynn
07-23-2008, 10:54 AM
Did you see my link awhile back to both PCMCIA and PCi *real* serial port cards?

sam
07-23-2008, 03:54 PM
Nope. Didn't see that.

I will do a search for it right away :D

Adrenalynn
07-23-2008, 04:44 PM
Save you some trouble - I've ordered from these guys before, they're pretty good in my experience:

PCI Card
http://www.microbarn.com/details.aspx?rid=100216

Less expensive source I'm not familiar with personally: http://tekgems.com/Products/tg-lava-dual-serial-pci.htm

Here's a PCMCIA/PCCARD/CARDBUS/WHATEVER THEY CALL IT TODAY: http://www.allserial.com/pcmcia_mg-2scb_serial_adapter.htm

ooops
07-23-2008, 05:27 PM
Save you some trouble - I've ordered from these guys before, they're pretty good in my experience:



You are the greatest ... what is really frustrating is that I would bet the $70 or so that I have cases of these here somewhere.

sam
07-23-2008, 05:37 PM
Hum, that looks nice! I was actualy thinking of adding that to my computer but itès old and I will probably change it very soon, so I donèt want to have Vista then I canèt use the USB to serial thing in my next computer. I will retry my USB to serial converter with another computer to see if it works.

Adrenalynn
07-23-2008, 06:07 PM
Just sooo many things you can't do with a USB->Serial dongle... Try a real UART - All the kids are doing it. :)

ScuD
07-24-2008, 01:47 AM
Try a real UART - All the kids are doing it. :)

Sounds like one of those "join the army" posters from the 40's :happy:

But you're right, even though I do use a USB-to-UART for practical reasons only (simple to plug in to the front of my desktop and does what it needs to) I still couldn't do without a real UART.
Even though I don't do a lot of pc-based programming, the programs I do write usually use serial commands and/or just a pin in need of driving.
Try driving pin TxD high with a USB to serial converter :wink:

Adrenalynn
07-24-2008, 02:38 AM
Sure, or twiddling CTS/RTS, or strobing DSR. And the worst thing where robotics is concerned is that they frequently can't be coerced into driving a programmer - especially where PICs are concerned. The Atmel programmers are smarter, they have all the bit twiddling onboard, but most PIC programmers (especially the affordable ones) don't.

I put an 8 port PCI 16C950 card in my robotics lab machine. Overkill, but you just never know. I wasn't lacking for a port when I decided to drop my old Davis weather station in the lab. ;) And they're so dirt cheap. A little two port can be had for less than ten dollars...

ooops
07-24-2008, 10:56 AM
Ok here is the Mini-Moody-Gerwalk all ready to go.
http://forums.trossenrobotics.com/gallery/files/1/7/7/8/gerwalk-1.gif

I didn't spend any time cleaning up the wires.
I can't wait to get "it" walking, hopefully tonight.
Will keep this updated.

sam
07-24-2008, 11:04 AM
Looks nice! I love the head it makes it looks really funny and gives it a pupet look to it.

ooops
07-24-2008, 11:26 AM
I hope it and I are still smiling after the walking starts.

ScuD
07-24-2008, 03:27 PM
Mwuhahaha...

Looks like an evil assimilated sock puppet that creeps out of the kids closet at night..

I thought about building that one when i got my bioloid kit too, but I decided to go directly for the humanoid instead...

Looks cool! we want vids!!

ooops
07-24-2008, 06:37 PM
we want vids!!


Video will have to wait a day. My much needed parts were delayed "due to weather" in Philly.
So, until tomorrow it is still just a static evil assimilated sock puppet:(
If I knew I had the extra day, I might have went ahead with the Humanoid, but in my haste to bring "life" to a bot, I went for quick over big.

ScuD
07-25-2008, 02:20 AM
I understand completely.

In my case I just figured, if I build another bot, once I upload the standard example program, I'll probably just take it apart and build the humanoid, so that'd take me another evening of building.