Rotate under force control

martini

Hi.

   I am stuck in this problem and dont know how to solve this..Please take a look.

So, the problem statement is... 

I want to rotate under force control from an oriented pose to a pose where my Ex and Ey are zero...(or trivial values... like 180 etc) but this transformation doesnt involves any rotation about Z axis..

Another condition is that i have to rotate about the base X, Y axis.. So, that means, i have to rotate in what is called "Fixed axis" and not Euler axis..

In order to rotate about this fix axis, i need to calculate the angle..this rotation angle in X and Y.. which means, that how much degrees i should roatate around the base X axis and base Y axis.... so that it reoriente to the pose i want.

So, the problem is i cant use EulerZYX etc directly as (yeah you guessed it right) this is EUler ZYX notation which is moving axis notation whereas my rotation is about the base fixed axis...

So, i wrote a simple transformation function which changes this Euler ZYX to this XYZ notation..

but the problem is.... the angles are valid... if my tool is coinciding with the wrist 6..i.e if i use tool0... but.. i want to find the rotation angles about any tool..i.e TCP can be any reasonable point...??

Please help me how to solve this problem.

its driving me crazy..:((

Henrik Berlin

The EulerZYX convention and the RPY convention (used to rotate around a fix coordinate system) are in fact the same. The difference is that you rotate in the order ZYX around the "new" coordinate system with EulerZYX, and in the order XYZ around a fixed reference coordinate with the RPY (Roll-Pitch-Yaw) convention. But the result is the same.

Please clarify your question.