When a slingshots sling is slack, there is no energy in the system. When the sling is stretched back, it contains potential energy. When the hand releases the sling, it starts moving forward. When the sling starts moving it would then have kinetic energy. Let's correlate kinetic energy to robots.
Kinetic energy is the energy of moving objects.
The faster an object is moving the more kinetic energy it has. This also means that this energy is the energy of work. As the robot starts to pick up speed, the kinetic energy grows. When the robot rolls to a stop in a mangled heap, the kinetic energy then has been changed into other types of energy such as heat. Potential energy in robots can usually be seen when two robots get into a pushing match.