After all that we had discussed in June 2008 – cable ball connector, spring settings and their modifications, the new Otto Bock MovoHook that I got a bit later, and Brad who asked for photos of the MovoHook – it seems that Bradley Veatch released a new hook through PhysioNetics through ADA Technologies.

This interesting product termed V2P prehensor seems to feature near car-lifting strength spring setting, and looks like the Hummer of All Hooks or even a weapon. I like its appearance but the ultimate interest is in its function. The V2P also features non-linear spring settings.

I now use a pimped version of the Otto Bock MovoHook and a new wrist joint that we built ourselves (currently MSM wrist 0.1-rev, details freely available for download if you want to build one as well), and that covers all aspects of my daily situations with some rare exceptions that are probably inherent to hand prosthetics rather than a specific solution. Most notably, the MovoHook contains two sufficiently useful spring settings, looks like a conventional hook, features a rather optimized and refined hook claw shape and is quite lightweight.

The new V2P prehensor takes the Otto Bock MovoHook concept further by allowing what seem to be ultra heavy spring settings:

This is a great development, and it is great to see competitive improvements for cable controlled prosthetics. After all, these are – compared to myoelectric devices – powerful, affordable, robust, temperature independent, resistant to humidity and water, rugged and their control feels natural and force application can be naturally graded.

So, cable controlled setups should not be discarded as prosthetic technology but developed further. As first step, one should now compare these recent hooks variations and provide a detailed feature list for any supplementary issue.

I strongly believe that it is indeed the first step to pull any design feature out into the domain of Open Prosthetics or at least market the products along with the option of documenting failure and requesting features or fixes. As customers we are often extremely well able to pinpoint advantages and problems fast and precise but instead it feels as if we are treated as mentally retarded. There are distinct exceptions that I have to mention – John Becker of Becker Mechanical Hands and Brady Veatch of Physionetics both have bent over backwards to satisfy customer requirements.