Designing an Apple Watch on a Prosthesis Hand

Project Info


Designing a Supplementary Mechanism to Match an Apple Watch on a Prosthesis Hand.


This project belonged to one of our clients, who requested a watch for a prosthesis hand.

The watch was an expensive Apple brand watch and we were asked to design it for a prosthesis hand.

Usually, the buttons of watches rotate horizontally; however, the users were not able to rotate the buttons on such existing models. Therefore, the Client asked us to design a mechanism to have the buttons installed in a perpendicular orientation, in addition to sustaining the same functionality.

Another challenge was encountered when the client asked to keep the clock unchanged. Therefore, we had to design a mechanism so that without changing the clock, it would be possible to transfer the horizontal movement of the clock into the vertical movement, and we solved this challenge by using worm gears, wedges and creating holes appropriate for the clock buttons.


We first made the general concept for the project, then made the calculations and finally designed the corresponding mechanism to meet the following two requirements:

  • Changing the direction of the vertical rotation to a horizontal rotation
  • Changing the position of the clock’s pushing button from the side to the surface of the prosthesis so that it can be easily accessed.

In order to do this, we made use of worm gear & worm shaft. This method was welcomed by the client, was 3d printed and is now being easily used.

Watch the process:


Result and Impact:

The final product was designed and submitted to the client with the related 3D photorealistic renderings as well as an animation video of the product to show its functionality and illustrate the product’s working mechanism.
The technical drawings, pre-manufacturing drawings and CAD files (STL and STEP files) were also provided to the client to be used for the prototyping and manufacturing stages.

Evan k.
December 25, 2017
USA, Florida
Mechanical Engineering