Project video: https://www.youtube.com/watch?...

Multipurpose Pneumatic Grip Assistance (MPGA)

This project is an entry for the Within Reach contest. It's goal is to develop and provide a useful tool for those with reduced hand mobility. 

With the MPGA I've tried to achieve the following goals:

• Develop a multipurpose(-ish) device, that enables one to handle tools and objects required to execute basic ADLs.
• Develop a device that doesn't require external tools and objects to be somewhat fitted, adapted or specialized (i.e. works with regular off-the-shelf objects)
• Come up with a device that doesn't couple the wrist motion to a gripper (which seems to me as restrictive to the user's ROM)
• Devise some sort of mechanism that provides stable grip of an object, without requiring the user to continuously apply force to the object (useful for long manipulations, specially for users with reduced hand strength). 

I essentially tried to answer the question: what kind of "assistive swiss-army-knife" would I like to have with me while traveling?

To achieve this goals, the MPGA employs a pneumatic system. A pump and positional switch drive a pneumatic cylinder. The cylinder open and closes a foam-coated gripper. The setup provides a strong and stable grip, capable of holding cutlery, toothbrushes, hairbrushes, shopping bags and more. 

The positional switch controls if the gripper opens or closes. It is placed in such a way that an user can easily and quickly switch it on their forearm or legs.

The pneumatic system allows the user to gradually increase the pressure in the cylinder without having to exert high forces with their hands. It also keeps the gripper in place after pumping has ceased, which means that an user can manipulate an object for long periods without submitting their hands to continuous loads or stresses.

Additionally, a cylindrical recess on the side of the MPGA helps users to hold pens and pencils. 

The pneumatic system uses the robust and readily available parts from LEGO® kits. However, future versions of the design will employ more commonplace parts.