Go beyond your limits
The aim of this project is improving the life quality of paraplegic users.
The autonomy is a combination of accessible environment without architectural barriers and good technical aids. This device offers assistance reducing push effort during all transfers, the use of it offers advantages in daily life, reducing tiredness and inflammation of upper articulations, it also allows you to travel for more long distances.
In this project the user must be at the heart of the research, so I have started to understand the needs of patient after some really important interviews, and this is what I’ve found.
Mercedes-Benz EQ product
If an automobile brand start the production of a medical aids, this is perceived as a transport, maybe sporty or luxury, so this fact can take away the idea of something ugly
The future is electric and intelligent. Intelligent electric mobility this is what the new Mercedes-Benz EQ product brand stands for. An attractive design, exceptional driving fun, high levels of suitability for everyday use and maximum safety are further attributes. EQ represents the two Mercedes-Benz brand values of “emotion and intelligence” and comprises all significant aspects of customer-oriented electric mobility.
Biomechanics
In recent decades the study of biomechanics in sport has increased, I was searching the best frame dimensions but I have found a non-answer: Everyone have a different body so when we build something to interact with that, we need to give a large possibility of customization because there isn’t absolute perfection.
Point of Calibrate (POC) trim adjustments were inspired from the world of bicycle, where the frame is stationary and the seat can move in height, depth and incline with a single adjustment element.
The frame
The three wheels geometry can already be found on the market and it allow to reduce weight and dimensions. The frame is in carbon fiber for excellent technical features like stiffness and lightweight, an interesting feature is the variable thickness, so with FEM analysis I understand where it’s possible to reduce thickness, the result is a frame weight of 995 grams.
The Seat
Users have a lot of different cushions for different pathologies (like for prevent bedsore) all of these pillows have in common that they need a rigid lower plate for support. The seat will be a single CFRP sheet with a central joint connect to the frame.
Tarta is an Italian company that produces the best backrests on the market for wheelchairs. Their technology for the back is modular, customizable in height and width, and the structure is in harmonic steel for give to user maximum freedom. I have redesigned the backrest for a better integration on this vehicle.
drive dynamics
Haptic feedback is the main theme for development of a great product.
The electric motor intervenes to help push, but it does not replace it, so the electric motor distributes more or less power depending on how much force we push on wheels. The electronic are plan to reach a maximum speed of 6 km/h (Italy regulatory limit) favoring the battery life, over that speed electric motors will not attend anymore. The peculiarity of this architecture is not to alter the users experience of a classic muscular wheelchair.
Inside the frame we find all necessary components: a 100w motor for each wheel that allow more precision in the guide; a 300Wh battery (according Bosch it should last 60km or 6 days); a chip at the front of the frame that manages the distribution of power between two wheels (a 24V voltage allow us to use it without the relay).
Scale Model
I started with a raw model up to the result of 1:2 scale model, frame and wheels are CNC milled, thermoforming for platforms and 3D printing for seatback and details. The assembly was the hardest task, but luckily all the parts fit great.
Talking to some patients they really like it and would like to see it on the market.
