I want to measure the acceleration of the slider (orange color) that moves along a table (green one). The green element rotates around an edge of the fixed table (red one). If the slider has a constant speed, with respect to the green element , the acceleration should be zero.   And it is, but only when the green element does not move.  Do you have a suggestion on how to measure the correct acceleration of the slider?    The model is made in SW 2010 x64.  All the best!