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Society of Robots  Robot Forum
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Mathematical Model
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Topic: Mathematical Model (Read 758 times)
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saba_rish91
Jr. Member
Posts: 25
Helpful? 0
Mathematical Model
«
on:
January 21, 2013, 10:08:51 AM »
Hey,
I'm building a quadruped robot. I need to find its mathematical model. How do I start?
I did try to find few papers on that. But, it didn't help me.
Please help.
Thanks in advance.
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Gertlex
Supreme Robot
Posts: 757
Helpful? 23
Nuclear Engineer · Roboticist
Re: Mathematical Model
«
Reply #1 on:
January 21, 2013, 11:56:38 AM »
There's various aspects... You weren't clear on what you need.
Here's a forum thread where forces on the servos are discussed.
http://forums.trossenrobotics.com/showthread.php?53494DOFlegmechanicsandtorquerequirements
As for the actual walking gaits, there are a few different ones. The NUKE code implements and documents them.
http://code.google.com/p/arbotix/wiki/NukeTuning#Gaits_Included
Finally, there are a couple of .gif animations in this thread's first post, which demonstrate the movement being done. On a single leg, it's purely a geometry problem. Then with four legs, you just have to figure out how to offset the four legs' movements to get actual walking.
http://forums.trossenrobotics.com/showthread.php?4929My4DoFQuadMechNuma
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saba_rish91
Jr. Member
Posts: 25
Helpful? 0
Re: Mathematical Model
«
Reply #2 on:
January 22, 2013, 11:10:23 AM »
In the thesis (link below)
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.12.2818&rep=rep1&type=pdf
Page 41, in equation 3.6, the vector rBH is constant and hence the derivative must be zero. But, in the next equation (3.7), he has multiplied it with the rotation matrix. I don't understand how he arrived at this.
Please help.
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Mathematical Model
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