I'm trying to find screw axes for joint (on pic) with angle θ. It's on zero position. As I understood:
- joint has an angular velocity on the Z axis, clockwise, so the sign is positive and ω=(0,0,1);
- joint is located at height L along the X axis, so v=(L,0,0).
But right answer is [0,0,1,0,-L,0]. Why?