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Inverse Kinematics with Dynamics

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Hi developers! I'm trying to write an algorithm that performs IK with dynamics. Remember that IK is the problem to set robot articulations for reaching a goal. Well, in this time, is needed to set the articulations of a robot builded on a physics engine (ODE). I've do some, but it doesn't work fine. On ODE, motor controllers behave so lazy. Please watch my demo at: http://www.usuarios.lycos.es/tripticon/Robotica.zip Camera controls: arrow keys, A,W,S,D. Goal target controls: <DEL>,<END>,<HOME>,<INSERT>,<NEXT>,<PRIOR> Activate effector: <SPACE> Do you have any suggestion to do IK with dynamics?

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I assume by lazy you mean weak and slow? Try lowering the mass of your arm sections, and increasing the torque of the motor. Your robot looks really weak, but most are rediculously over powered. Also you should iterate your IK many times before you actualy send it to the robot, then given alot of torque it will be powered to the correct target. What is the specific application of your robot? Most robots are not solved on a iterative method, but a "fixed" joint crunching pipeline. Then the robot uses acceleration to aproach a point smartly, instead of over shooting it.

But honestly it looks good so far, just a little weak.

edit: I like the telescoping tip. This isn't a laser cutter is it?

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Thanks honayboyz!

And know watch my fixed robot!! I've found the problem:
In the past, the program fix every joint applying torques directly with this command:
dJointAddUniversalTorques(dJointID joint, dReal torque1, dReal torque2)

With forces, the robot doesn't work with accuracy, and it tends to show so weak. (bounces and staggers).

And now, I've found that set velocities gives to it more control, because motors are velocity safe, so I have to use this command:
dJointSetUniversalParam (joint, dParamVel, torque);

Watch it now at:
usuarios.lycos.es/tripticon/Robotica2.zip


However, I can't get it to move faster. The program cannot do IK as iterative process; it does one iteration per world step in ODE! Any suggestions?

[Edited by - leoptimus on December 5, 2005 7:07:44 AM]

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