A useful development is presented here: new body powered socket and gripper technology primarily aimed at children.
This development appears to avoid the 'single individual or competitive company charging into patent market derailment with a stalled / stalling product'. The thing is that rare / orphan disease rules play out. It is not acknowledged by many but the clever players play by these rules, for sure. Because one thing is for sure - below elbow amputees are rare - only half wear prosthetic arms - about half of which are probably body powered. Those are so few out and far that economic laws of free markets neither work nor play out. With any new patented invention you won't change shit. Rather, people that use conventional marketing of their usually not too inventive products are responsible for stale product ideas and stale products, for immature developments and bad manufacturing. Commercial prosthetic arms are one big proof for the term 'stale' - look around and ponder. Patent applications are harmful and keep products or solutions from the market for another few years until - how so often - just about nothing really happens. But, not here.
The Delft University of Technology is a government supported institution that works on a whole line setup that appears to be well researched and solves actual problems. Solutions are published and made available. Great stuff.
The Wilmer system provides for hidden cables. That is one advantage to make it more appealing to everyone, particularly kids. Also it makes it a bit easier to connect and disconnect.
Images (C) Copyright WILMER / Delft University of Technology
They have a whole line of products - wrists, hands, hooks and prehensors (below), all fast to switch with quick lock wrist units.
Their cable control operates without harness. Instead, an elbow brace is employed.
The elbow brace appears to be set up with some padding.
Here is a diagram showing how the elbow brace allows for opening and closing of these voluntary opening devices.
That is how it looks on a real prosthetic arm, obviously this is rather light weight technology.
This shows the design of the prosthetic hand.
This shows the Tweezer prehensors used to fit children.
Convincing demonstration of speed and ease of body powered control of the Delft WILMER system: