Raptor: 3-D printed prosthetic hand

I designed the Raptor to be a basic terminal prosthetic hand that could be 3-D printed. There are only 4 pieces that are printed and they can be made at a home printer.

I designed the Raptor hand for a design competition on GrabCAD. As of this post the competition is still up.

If you would like to print the Raptor yourself here are all the files that you need

If you would like me to design a custom application prosthetic for you feel free to contact me.

Here was a demo of the prototype. I used shockcord and paracord as the cables which is way to bulky. In future I will likely use small steel cable a maybe just rubber bands.

Rugged Prosthetic Arm Concept

I have wanted to build a heavy duty prosthetic for awhile. So I decided to get a basic concept design in CAD.

In the Slant Rugged Prosthetic 0.8, the elbow is supported by a bike spring. I downloaded the spring part, because of that the spring is a quite a bit larger than I would use in practice.

All the pieces of the arm are machined aluminum plates. This drastically reduces production costs of the prosthetic.

This arm is intended to be used by amputees with an active lifestyle. Its won't break and certainly won't short circuit. It could be used on snowmobiles, bikes, or water skis to give the amputee greater control and balance on the vehicle. It also allows for the user to perform heavier duty lifting, such as moving 2x4's, something no other prosthetic could withstand.

The passive design is a limitation since the arm is stuck in a particular static position, until the user basically leans into it. This is fine on an ATV, but not when moving boards around. (Check out my exoskeleton to see this problem in action)

Fortunately the design can easily be changed from using a spring to using a linear actuator. A slight adjustment in the fastening locations on the arm and a person would have a super strong arm, which would only require a very basic controller to operate.

But most of all this arm would be cheap. Maximum manufacturing cost would be around 200-400 dollars.

The next step will be to layout the manipulator and its attachment.

Slant Concepts

Slant is the reincarnated version of Universal Mechanisms. While still basically in development we are operating with what we have.

Slant is a product micro-production and development firm. We focus on the creation of a quantity of ideas instead of a quantity of product units. Meaning we like to try one thing and if it doesn't work we move on to the next. Instead of working to develop the "One-Hit Wonder" of products we work to create good products for niche markets. We are the opposite of the mass production model.

Since Slant is based on micro-production we focus on the creation of products that can be stored digitally, which eliminates the need to store physical inventory. This means that we do a lot of 3-D printing and self-publishing. Something is made when it is purchased.

I currently run Slant alone from a dorm room. But when I need help I bring in friends and free-lancers. I suppose that 'we' is really just the rolodex of people that have helped when Slant was UniMech and will be helping with the development of Slant in the future.

Power Claw

The Power Claw was an early prototype for an ultra-strong prosthetic/exoskeletal hand. It had over 100 lbs of gripping force using the simple linear actuator assembly. It was made from solid steel which made it far too heavy to be usable, but I was able to get a feel for the proportions and the effectiveness of the gripper arrangement.

This type of prosthetic, once fully developed, is for those who wish to have an extremely active and dirty lifestyle. Most prosthetics today are dexterous by very delicate. I wanted to work on the other end of the spectrum for those who will want to ride snowmobiles and work in construction.

The Power Claw would also be useful as a kind of "metal glove" for those that want to have a tougher hand for certain jobs.

I intend to re-work this hand in machined aluminum. I've also have found linear actuators that are faster, stronger, and more compact. This prototype will probably be added to the SPExs suit prototype.