With joint displacement, the weights are set based on intuition and experimentation, and although the postures obtained by minimizing joint displacement are acceptable, the question arises as to whether or not there are more practical, less ad hoc approaches to setting the weights. This proposed performance measure stems from difficulties with the above-mentioned joint displacement function and from deficiencies in an existing performance measure that depends on the potential energy of an arm (Abdel-Malek et al., 2001aвЂ“d Mi et al. However, implementing an energy function as a human performance measure requires special considerations. Potential energy is a well-understood basic concept and has been used successfully as an objective with robotic movements. Abdel-Malek, Jasbir Singh Arora, in Human Motion Simulation, 2013 3.7.3 Delta potential energy Nuclei in atoms have potential energy that is transformed into more useful forms of energy in nuclear power plants. An explosive substance has chemical potential energy that is transformed into heat, light, and kinetic energy when detonated.

For example, electrically charged objects have potential energy as a result of their position in an electric field. Potential energy manifests itself in different ways. For example, when a ball is held above the ground and released, the potential energy is transformed into kinetic energy. Potential energy also can be transformed into other forms of energy. In fact, the amount of potential energy a system possesses is equal to the work done on the system. It takes effort to lift a ball off the ground, stretch a rubber band, or force two magnets together. Work is needed to give a system potential energy. Other examples of systems having potential energy include a stretched rubber band, and a pair of magnets held together so that the like poles are touching. For example, if a ball is held above the ground, the system comprising the ball and the earth has a certain amount of potential energy lifting the ball higher increases the amount of potential energy the system possesses. Potential Energy is defined as the stored energy possessed by a system as a result of the relative positions of the components of that system. Cheremisinoff Ph.D., in Condensed Encyclopedia of Polymer Engineering Terms, 2001 POTENTIAL ENERGY

Potential energy and workdone