Before this change, xipos[0,1,2] was only set to 0 by mj_resetData zeroing the entire buffer.
When using mj_resetDataDebug, the value would be wrong.
PiperOrigin-RevId: 450939814
Change-Id: I887dd977161c7d132a80b766db7be23350ffb50b
Added analytic derivatives of smooth (unconstrained) dynamics forces, with respect to velocities:
- Centripetal and Coriolis forces computed by the Recursive Newton-Euler algorithm.
- Damping and fluid-drag passive forces.
- Actuation forces.
A new implicit-in-velocity integrator is implemented using the analytic derivatives. This integrator lies between the Euler and Runge Kutta integrators in terms of both stability and computational cost.
PiperOrigin-RevId: 450377010
Change-Id: Ie192b441876c22e732fb749333926f296e0a09cc