Aug 14, 2022
This year, my friends and I placed second out of sixteen teams in the annual Engineering Physics summer robot competition. Each team had 10 weeks to design and build a fully-autonomous treasure hunting robot from scratch. Here’s the story.
- In-depth competition overview and rules
- Central GitHub repository with firmware, electrical simulations and PCB designs
- My interview with Today in BC
- Serhii’s LinkedIn post
The theme of this year’s competition was Treasure Hunter Bots. Each robot had to autonomously navigate the course by means of different sensors while picking up treasures (1 point each) and carrying them to the finish (an additional point). However, one bomb—identifiable by a small magnet in its head—is a “bomb” and picking it up ends your run.
A full overview and ruleset can be found here.
During our design proposal we broke the course into the following six steps:
1. Follow tape and climb the ramp
Three reflectance sensors on the front of the chassis allow for PID tape-following up the ramp.
2. Collect the 1st treasure
Eventually, an ultrasound sensor on the right senses the presence of the first treasure. From there it is picked up by way of a series of hardcoded encoder movements and front sonar readings.
3. Cross chicken-wire and collect the 2nd treasure
The robot loses its reflectance measurements when it crosses the chicken wire. When that happens it drives forward and scans for tape.
The second treasure is collected similarly to the first. However, because of the wall behind an additional sonar pass is required to locate it.
4. Navigate archway, isolate and follow 10kHz beacon, collect 3rd and 4th treasures
The archway is extremely tight—bumpers help guide it through.
Movement through the hallway is the most complex of the course. In brief:
- The infrared signal from the 10kHz beacon must be separated from the 1kHz beacon. This is done by sampling the ADC on the microcontroller extremely quickly (~47kHz) by using the onboard direct memory access (DMA) controller.
- Sonar cannot reliably distinguish the treasures from the surrounding rocks. Clever trickery and encoder movements are required.
5. Deploy and cross bridge
The robot is centred by ramming the infrared beacon with the front guide. From there the robot turns and aligns itself with the gap edge using rear reflectance sensors.
The bridge is deployed and aligns itself with a combination of metal tabs and force from the wheels.
6. Collect last treasure and drop box on finish platform
An intricate ballet of hardcoded movements and sensor measurements. Once the robot is ready to deliver the treasures, a servo releases the box which rolls on bearings off the platform. It is caught over the finish using two steel cables.
A brief overview of our process
This course was the most concentrated learning experience of my life and I am immensely blessed to have worked with the best team one could ask for.
I’m starting to feel like a real engineer and I cannot wait to work on more projects.
I would love to hear what you thought of this post. Loved it? Hated it? Want to share your hand-written poem with me via carrier pigeon? That might be challenging—try sending me an email.
You can get updates when I post something new.