Design a Safer Bicycle Experience
Biking through the city can be scary due to the high congestion of cars. More than 30% of the bicycle accidents are caused by car collisions. It is crucial for cyclist to be aware of their surroundings at all times, but more importantly, to be visible to others.
"I have 75 to 80 cases going right now. Almost every one of those, the car drivers never see the bike. They don't see us because they're not looking for us." said John Duggan, a Seattle-based attorney who often represents injured cyclists.
After researching the different solutions to improve cyclists' visibility, I decided to design a product that has the function to light up and warn the driver when a vehicle is too close, while also vibrate to alarm the cyclist.
Starting off ambitiously, I choose to work with these three components: LED strip, LIDAR-Lite sensor, and vibration motor. I brainstormed a couple placements, and decided to go for the saddle bag direction due to two main reasons:
- LIDAR-Lite sensor will be more stable attached behind the bike than on a helmet.
- The closer the sensor is to vehicle, the more responsive it is, and detects vehichles more acurrately.
Applying Arduino to Product Design
Expectation vs Reality
As a beginner learning to use Arduino, I was not aware of the various limitations. The Arduino recommended range of voltage is 7V to 12V. Adding the LED strip would exceed the limit. So I quickly came up with a new design to adapt the situation, by replacing LED strip with 10mm LEDs that require less voltage.
Transforming ideas to working code and circuit was challenging. Due to the time constraints of the project, I eventually took out the vibration motor and focused on the core function - LEDs response to sensor.
The final design of the bicycle lidar will light up when the Lidar-Lite sensor detects an object within 2 meters, a general safety distance.
Testing code, and more testing.
Takeaway - If plan A doesn't work try plan B. If plan B doesn't work try plan C. If there isn't a plan C then come up with one.
There were many up and downs in the prototype testing phase. I learned to always prepare for the worst. I decided to leave an opening in the saddle bag due to two reasons:
- to update code at anytime
- to unplug batteries when not used