Fully Analog Line Follower
Autonomous line following with zero microcontrollers — just IR sensors, comparators and analog feedback.
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Overview
This project deliberately avoids any microcontroller: it's a line-following robot built entirely from discrete analog components — op-amps, transistors and comparator circuits doing the job usually handled by firmware.
IR sensors read the line contrast, feeding into comparator-driven control logic that directly maps sensor differential to motor drive signals. The result is a robot with essentially zero decision latency — the response is limited only by the analog circuit's bandwidth, not by a CPU's loop time.
The tradeoff, of course, is flexibility: every behavior had to be designed and tuned in hardware rather than software, which meant a lot of iteration on component values and comparator thresholds on the bench before the robot tracked reliably.
Key Features
- 01Zero microcontrollers — fully discrete analog control circuit
- 02IR-based line sensing with comparator-driven differential steering logic
- 03Op-amp based analog feedback loop for continuous path correction
- 04N20 DC motors (300 RPM) selected for torque/speed balance on the analog drive stage
- 05Mechanical chassis modeled in SOLIDWORKS, PCB laid out in Altium Designer