# LineMaster Pro: A Low-Cost Intelligent Line Following Robot with PID Control and Ultrasonic Obstacle Avoidance for Educational Robotics

arXiv: https://arxiv.org/abs/2603.13907 · HTML: https://mlsanity.com/paper/2603.13907/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 1 of its 34 references that are in the map.
- First posted on arXiv 14 Mar 2026.

## Builds on (most cited first, 1 of 1)

- [MecQaBot: A Modular Robot Sensing and Wireless Mechatronics Framework for Education and Research](https://mlsanity.com/paper/2411.13156/) (2024)

## Abstract (arXiv)

Line following robots are fundamental platforms in robotics education, yet commercially available solutions remain prohibitively expensive (150-300) while lacking integrated obstacle detection capabilities essential for real-world applications. This paper presents LineMaster Pro, an intelligent low-cost line following robot implemented on an Arduino Nano platform that integrates dual TCRT5000 infrared sensors for precision line tracking, an HC-SR04 ultrasonic sensor for real-time obstacle detection, a digitally tuned PID controller with Ziegler-Nichols optimization, and a hierarchical finite state machine for robust obstacle avoidance. A systematic four-phase sensor calibration methodology ensures reliable operation across varying lighting and surface conditions. Experimental validation through 200 controlled trials and 72-hour continuous operation demonstrates mean tracking accuracy of 1.18 cm at 0.4 m/s (95% CI [1.06, 1.30]), obstacle detection reliability of 96.7% within 10-40 cm range with 0.7% false positive rate, and 94% successful recovery from path deviations. The PID implementation achieves 43% improvement over conventional on-off control (p<0.001). At a total hardware cost of 28.50 based on verified Bangladesh market prices, LineMaster Pro achieves a 94% cost reduction compared to commercial alternatives, establishing a practical benchmark for accessible robotics education in resource-constrained environments.