Never in my wildest dreams would I have thought I would get to work on this iconic creature from Star Trek: The Original Series. 

This was an interesting challenge because the brief changed so many times. At first, they wanted to be able to run 100 of them, remotely and simultaneously down a hallway. Due to logistical constraints, it was lowered to 20. Even with 20 tribbles, we had to figure out a way to limit the number of operators needed. This was the main challenge for our electronics team.

They designed a system such that there were groups of “leaders” and “followers”. Each leader would be remotely controlled while a group of followers would follow the leader, minimizing the number of operators needed. Each follower and leader had a custom designed circuit board.

The mechanical challenge of this project was to mimic a “crawling” motion in a controlled manner (although, we’re not sure if tribbles actually have limbs). In the prototyping phase, we used two motors to “drive” it forward, with a third as balance. The two main motors would have offset wheels.We experimented with different RPM, different sized wheels and the distance of the offset. After initial testing, we realised that this method would not be easily controllable due to the amount of bouncing that happened due to the nature of offset wheels. Going back to the drawing board, we decided to go with a classic RC car chassis with treads. This helped with uncertainty of the terrain of the set and maneuverability. In addition, we added a third motor, attached to a weight at the end of a spring to make the tribble vibrate and for it to feel living. 

We patterned the fur to cover everything. One issue we came across was that the fur would get caught around the wheels and axles. If we altered the pattern or trimmed the fur back, it would show the mechanical elements. The solution we came up with was a discreet internal skirt that protected the insides from the outside.