Our invention is a cost-effective feedback based prosthetic leg for above-knee amputees. Currently, the majority of amputees in India depend on low functionality mechanical legs like ReMotion knee, Jaipur limb, etc. because of the cost of a high functional feedback based leg (70000 dollars) which middle-class people can’t afford.
All mechanical prosthesis like Uniaxial Knee, ReMotion limb, locks and transfer load to the ground only when the load is acting normal to the ground; when the leg is in a bent position won’t lock and the amputee may fall down. It won’t give any walking assist, it only provides support & drains more energy.
We incorporated a proportional solenoid valve controlled pneumatic damping system in a mechanical knee. The force sensor at the foot detects the pressure applied by the amputee and adjusts the damping resistance at the knee which enables to lock the knee joint at any angle and position correspondingly.
In costly prosthetic legs like OTTOBOCK C-LEG, damping at the knee is achieved using servo motor controlled valve which is costly. We replaced servo controlled damping system with a proportional solenoid valve controlled damping system which works similarly and at a very low cost compared to the former. We also used HDPE for socket making instead of carbon fiber which reduced price without compromising safety.