The document describes an idea for enabling autonomous vehicles to safely pass each other using an algorithm and ultrasonic sensors to coordinate speed. It discusses issues with using noisy ultrasonic sensors and the processing limitations of single-board microcontrollers. A proof-of-concept was developed using a Zumo robot controlled by an Arduino interfaced with additional position sensors via a second Arduino to overcome these issues. Diagrams of the system block diagram, states, and circuit are also included.

1. Automatic Speed Coordination
Built & Designed by Rohan Kotwani

2. The Original Idea
• The design evolved into a “smart algorithm” that would enable
autonomous vehicles to pass each others safely.
• Autonomous vehicles have become popular recently and this idea
could be useful in the near future.

3. Issues to overcome
• Ultrasonic sensors were noisy. The sensors were continuously sending
and processing data were sometimes unreliable.
• The microcontrollers that were uses, Arduinos, had only one clock
“timer” and a limited number of pins. Using all of the pins and timers
make the controller unstable.
• There was a lag time when pinging multiple sensors and executing
movements. It was reasoned that another microcontroller was
needed to interface the sensors.

4. Proof of concept
• A “ZUMO robot” controlled by an Arduino was the autonomous
system used.
• A second Arduino UNO was used to interface multiple position
sensors and communicate with the autonomous vehicle.
• Sensor data was interfaced the second microcontroller via the serial
communication interface.

5. Block Diagram

6. State Diagram

7. Circuit Diagram

8. The End