stem II

For the second part of our STEM class (STEM II), we complete a group Assistive Technology project. This project is designed with a client in mind who has a disability in order to help them in their daily tasks. For my group, we created an obstacle detection device for visually impaired wheelchair users. Through this project I learned a lot about the different workings of different sensors, specifically sonar and LiDAR.

Stem II Prototype

problem and goal

Problem Statement: An individual with a brain injury has difficulty navigating their home in a manual wheelchair due to impaired vision.
Goal: The goal of this project is to design an attachable device for a wheelchair that allows a client with a visual impairment to navigate their home with increased safety and ease.

design approach and prototype

Design Approach: For our design approach we decided to look at two main sensors, sonar and LiDAR. Sonar sensors would allow for obstacle detection within a specified range and would sense for dips in the floor, and LiDAR which would allow for detection of larger objects such as walls. Originally we were deciding between using either sonar or LiDAR sensors, but in the end, we decided that a combination would end up working the best.
Prototype: For our prototype, two sonar sensors were connected to the foot rest of the wheelchair and wired to two bracelets, one on the right hand and one on the left, which would cause a vibration whenever the user got close to a specific object. The placement of the sonar sensor is able to be adjusted based on whatever wheelchair it is on. The LiDAR sensor is attached to the top of the wheelchair (as pictured to the left) with two metal rods and 3-D printed parts that allow for it to rest easily on the handlebars of the wheelchair without harming them. Below I have attached some images of the original sketches of our designs as well as how they turned out.

sketch and prototype images

Prototype Sketch 1
Prototype Sketch 2
Prototype Sketch 3
Prototype Sketch 4
Feedback System
Sonar System
Sonar System
LiDAR System