Overview:
In the preliminary design review, we outlined three
distinctive designs for our project. Our group, which consisted of
seven people, dealt with separate subsystems, which included the
different modes of obstacle detection and information relay. In the
PDR we proposed the combined use of a LiDar sensor and stepper
motor to create a topographic map of the environment and obstacles
surrounding the wheelchair. We also proposed the use of a Raspberry
pi and a camera for obstacle recognition and detection. In
addition, we proposed the use of multiple sonar sensors for
detection that could be relayed via vibration or audio-based
feedback. The group also performed background research to examine
the strengths and weakness of competitors, which is documented
below. For the CDR (Critical Design Review) we chose to go with a
sonar and LiDar based obstacle detection system that relayed
information through vibration modules in wristbands to the user.
Due to certain difficulties such as a power demand for the stepper
motor, the group just chose to keep the LiDar sensor horizontal to
detect obstructions such as walls. On the footplates of wheelchair
were two ultrasonic HC-SRO4 sensors that could detect obstacles
within half a meter of the user. Depending on the side of the
wheelchair that there was a detection, either via the LiDar sensor
or sonar sensors, the corresponding wristband was vibrated as a
stimulus so the user could navigate in the opposite direction. Most
of the casings and platforms for the electronics were 3d printed.
Overall, the project was an enjoyable experience to work on, and
from it I gained plenty of technical skills.
Presented below are some of the documents from each stage
of the process:
- Background Research
- PDR Proposal
- CDR Design Document
- TRR Final Design Study
- Final Presentation