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Help with Biped Design and Implementation... Need Advice...

Discussions regarding building a walking robot at home. Most of the robots participating at Robo-One competitions are custom fabricated.
19 postsPage 2 of 21, 2
19 postsPage 2 of 21, 2

Post by Joe » Tue Dec 12, 2006 9:58 pm

Post by Joe
Tue Dec 12, 2006 9:58 pm

Personally, I don't see much point in building my own servo controller. I can control 8 servos for $20 (using Pololu's micro serial servo controller) or 32 servos for $40 (using Lynxmotions SSC-32). That's a couple bucks per servo — a lot less than you're going to spend on the servos themselves, to say nothing of the brackets.

I do see some value in making your own brackets and other parts, at least in some cases. Sometimes what you really need isn't available, or sometimes it is but it's too expensive. Still, starting with Lynxmotion or Bioloid and adding your own parts on an as-needed basis isn't a bad way to go. (That's what I did on my 4-servo biped, for example.

HTH,
— Joe
Personally, I don't see much point in building my own servo controller. I can control 8 servos for $20 (using Pololu's micro serial servo controller) or 32 servos for $40 (using Lynxmotions SSC-32). That's a couple bucks per servo — a lot less than you're going to spend on the servos themselves, to say nothing of the brackets.

I do see some value in making your own brackets and other parts, at least in some cases. Sometimes what you really need isn't available, or sometimes it is but it's too expensive. Still, starting with Lynxmotion or Bioloid and adding your own parts on an as-needed basis isn't a bad way to go. (That's what I did on my 4-servo biped, for example.

HTH,
— Joe
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Post by NullARC » Tue Dec 12, 2006 11:22 pm

Post by NullARC
Tue Dec 12, 2006 11:22 pm

Once you have purchased a controller, how then do you program each servo position for whatever motion you are attempting? For instance simply walking, or say standing up. When you have a pre-designed kit, you are given a programming environment, many times a GUI. Obviously you would have to program in whichever programming language your controller understands.

This is the biggest part that I think I would have trouble with.
I have the least experience in programming of all of the skills you would need to complete the project.
Once you have purchased a controller, how then do you program each servo position for whatever motion you are attempting? For instance simply walking, or say standing up. When you have a pre-designed kit, you are given a programming environment, many times a GUI. Obviously you would have to program in whichever programming language your controller understands.

This is the biggest part that I think I would have trouble with.
I have the least experience in programming of all of the skills you would need to complete the project.
"She'll make point five past lightspeed. She may not look like much, but she's got it where it counts, kid. I've made a lot of special modifications myself."
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Post by Joe » Wed Dec 13, 2006 12:49 am

Post by Joe
Wed Dec 13, 2006 12:49 am

NullARC wrote:Once you have purchased a controller, how then do you program each servo position for whatever motion you are attempting?

You don't program the servo controller itself; it just responds to commands by immediately doing whatever you've told it (i.e., to go to a certain position at a certain speed).

Those commands come from some other device, that you have to program with motion sequences (or whatever other approach to movement you want to take). Pick your favorite controller for that — it could be a BASIC stamp, or an ARM board, or a Zigbee connection to a desktop PC, or whatever. (Or, like in my 4S-1 robot, you have your controller connected to a desktop or laptop computer with a USB cable.)

NullARC wrote:This is the biggest part that I think I would have trouble with.
I have the least experience in programming of all of the skills you would need to complete the project.

Then I agree, writing your own sequencing software is likely to be a challenge. You should therefore consider choosing something that has software already available for it, like the SSC-32 (there's a Windows app for that that can spit out BASIC code) or the Bioloid controller.

Best,
— Joe
NullARC wrote:Once you have purchased a controller, how then do you program each servo position for whatever motion you are attempting?

You don't program the servo controller itself; it just responds to commands by immediately doing whatever you've told it (i.e., to go to a certain position at a certain speed).

Those commands come from some other device, that you have to program with motion sequences (or whatever other approach to movement you want to take). Pick your favorite controller for that — it could be a BASIC stamp, or an ARM board, or a Zigbee connection to a desktop PC, or whatever. (Or, like in my 4S-1 robot, you have your controller connected to a desktop or laptop computer with a USB cable.)

NullARC wrote:This is the biggest part that I think I would have trouble with.
I have the least experience in programming of all of the skills you would need to complete the project.

Then I agree, writing your own sequencing software is likely to be a challenge. You should therefore consider choosing something that has software already available for it, like the SSC-32 (there's a Windows app for that that can spit out BASIC code) or the Bioloid controller.

Best,
— Joe
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Post by srobot » Wed Dec 13, 2006 9:14 pm

Post by srobot
Wed Dec 13, 2006 9:14 pm

Hi,
:D :D :D :D :D :D I just got my book "build your own humanoid robots" a few minets ago I have not look at it yet thow!!!!!!!!
I have to go read now!!!!!!!!! :D :D :D :D :D :D :D :D :D :D
:D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D

bye
--srobot
Hi,
:D :D :D :D :D :D I just got my book "build your own humanoid robots" a few minets ago I have not look at it yet thow!!!!!!!!
I have to go read now!!!!!!!!! :D :D :D :D :D :D :D :D :D :D
:D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D

bye
--srobot
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