Ellie is a dog who lost her entire left hind leg over a year ago. The purpose of this project is to explore whether it is possible to fit her with a prosthetic in order to reduce the stress on the remaining back leg. This project was led by instructors Victor Martinez and Stephanie Phillips for the entire class of DEPD 2310 at Kwantlen Polytechnic University.
Inspiration & Identification
We started the project by first understanding Ellie’s daily routine from the perspective of her owner (Andrea) and some medical background from her vet (Yvonne). From here, the class was split into 2 groups, one was to work with the owner, and the other with the vet, in order to provide the best solution for Ellie.
Next, we looked at existing solutions on the market and realized that no solutions exist for dogs with the entire leg removed at the hip. From there, we researched hip amputations and prosthetics in humans in order to better understand the joint mechanisms and how individual parts are joined together and help on to the human body.
Group A who worked with the owner was able to capture videos of Ellie walking, running, for gait analysis. By analysing her gait, and comparing it to the gait of 4-legged dogs, we were able to identify the length of strides as well as where the prosthetic leg should be bearing weight. We did this by playing the videos in slow motion, and tracing the movement of her joints on a big sheet of paper.
Group B who worked with the vet was able to better understand Ellie’s bone structure. The removal of the entire leg from the hip meant that there was socket space for the prosthetic to rest on that would feel the most natural for Ellie. To do this, we would need the leg to be attached to Ellie with a body harness.
We did many days of brainstorming and finalized it down to 3 concepts:
After creating a check list of all the functions and tasks the leg is required to do, we voted the one in the middle as the final concept.
We needed a rigid structure for the leg to attach to the harness, so we decided to do a 3D scan of her entire hip area. We rented a 3D scanner from SFU and took a 3D model of Ellie’s hip. We had to bandage her up so the fur wasn’t in the way. The dots are stickers used by the scanner to triangulate
Following the 3D model, the class worked together on the harness and leg. During this process, we’re had to take more measurements of Ellie and continuously fit the different pieces on her to ensure a snug fit.
The harness encases the hip curve piece and the pins stick on through the bottom of the harness to connect with the hip joint piece.
The First Full Fitting
The project is still in progress as we continue to improve on our design.