Kinematics is used in astrophysics to describe the motion of celestial bodies and systems , and in mechanical engineering , robotics and biomechanics to describe the motion of systems composed of joined parts ( multi-link systems ) such as an engine , a robotic arm or the skeleton of the human body .
Mechanical engineering , robotics and biomechanics use it to describe the motion of systems composed of joined parts such as an engine , a robotic arm or the skeleton of the human body .