Unveiling Line Follower V4: Transitioning to 20-Channel Optical Array & Gallium Nitride Drivers

Line Follower V4 replaces our second-generation 15-channel QTR bar with a 20-channel high-density optical array, giving the control loop finer resolution on entry angle as the chassis crosses each chicane apex.

The bigger change is underneath the hood: our new half-bridge stage swaps silicon MOSFETs for gallium nitride transistors. GaN switches gate charge roughly an order of magnitude faster than silicon at the same voltage, which lets us hold a clean 40kHz PWM carrier without the thermal throttling that capped our V3 board under sustained load.

Bench testing on the Lab 204 test track shows a 42% reduction in steering-response latency through the tightest chicanes compared to V3, with no increase in driver-stage temperature after a 20-minute continuous run.