Here is a robotic prosthetic emulator that enables amputees to test different solutions to find the perfect fit and make better decisions. It is lightweight and suitable for users up to 250lb. Amputees and non-amputees can wear this (the latter group with a simulator boot and lift shoe). The keel portion of the device is robotically controlled.
As TechCrunch explains, this emulator allows patients to test different systems. More information is available here.