MOTION ENGINEERING

Most torque systems can be modeled as a double integral system with coefficients for inertia (Kaff), viscous (Kvff) and static (Kff) friction. Although this model is not perfect, it is an effective way of reducing the following error. The feedforwards on the XMP were based on this model. The challenge lies in finding these three coefficients... There are two major methods of feedforward tuning covered in this section: shape-based and measurement-based... Inertial force will result in a position error roughly proportional to the commanded acceleration magnitude. (i.e. The position error and commanded acceleration magnitude plots have similarly shaped traces.