Autonomous Speed Detection and Pursuit Robot is an embedded robotics project that demonstrates how a microcontroller-based system can detect the speed of a moving object and respond autonomously. The robot integrates multiple sensors and actuators in order to monitor objects, compute their speed, and initiate a pursuit behaviour when a predefined speed threshold is exceeded.
The system combines concepts from robotics, embedded programming and sensor integration. By processing real-time data from infrared and ultrasonic sensors, the robot can detect objects, measure their speed and distance, and dynamically adjust its movement.
The project was implemented using the Arduino platform and programmed in C/C++, highlighting practical applications of embedded systems, real-time control and autonomous behaviour.
The robot continuously monitors its environment using infrared sensors and an ultrasonic distance sensor. When an object passes between two infrared sensors, the system measures the time difference between the detections and calculates the object's speed.
If the detected speed exceeds a predefined threshold, the robot activates a pursuit mode. In this state, the robot moves in the direction of the detected object and attempts to approach it. When the robot reaches the object within a certain distance, it stops and signals completion using visual and sound indicators.
The robotic system is built using several electronic components connected to a microcontroller platform.
Microcontroller (Arduino platform) – acts as the central processing unit of the robot and coordinates all sensors and actuators.
Infrared Sensors – two sensors placed at a fixed distance are used to detect when an object passes in front of them and to measure the time difference required for speed calculation.
Ultrasonic Sensor – used to measure the distance between the robot and the detected object.
DC Motors – two motors control the movement and direction of the robot.
Motor Driver – allows the microcontroller to control the motors.
LED Indicators – provide visual feedback regarding the robot's current state.
Buzzer – produces an audible signal when high speed is detected or when the robot captures the target.
The robot operates through several sequential stages.
Monitoring Phase The system continuously waits for objects to pass in front of the infrared sensors.
Speed Detection The first infrared sensor detects the passing object and records a timestamp. The second sensor detects the same object shortly after. The system calculates the time difference between the two detections.
Decision Phase Using the known distance between the sensors and the measured time difference, the object's speed is calculated. If the speed exceeds the predefined threshold, the system activates pursuit mode.
Pursuit Phase The robot moves in the direction of the detected object and follows it while monitoring the distance using the ultrasonic sensor.
Capture Phase Once the robot approaches the object within a small distance, it stops and activates visual and audio indicators to signal that the target has been reached.
The object's speed is calculated using the following principle:
speed = distance_between_sensors / time_difference
The distance between the infrared sensors is fixed, while the time difference is measured using timestamps recorded when each sensor detects the passing object.
Programming Language C / C++
Platform Arduino
Hardware Components
Infrared Sensors Ultrasonic Distance Sensor DC Motors Motor Driver LED Indicators Buzzer
Concepts Applied
Embedded Systems Robotics Sensor Integration Autonomous Behaviour Real-Time Control
Several improvements could enhance the capabilities of the system.
Improving sensor accuracy and detection range Implementing obstacle avoidance using additional sensors Adding wireless communication for remote monitoring Integrating camera-based object tracking Implementing more advanced motion control algorithms
This project demonstrates the development of an autonomous robotic system capable of detecting the speed of moving objects and reacting dynamically through pursuit behaviour. By combining sensors, actuators and control algorithms, the robot simulates a simplified monitoring system and highlights important concepts from robotics and embedded systems development.
Alexandra-Maria Bîrlea
MSc Student – Applied Computer Science
Faculty of Automation and Computer Science
Technical University of Cluj-Napoca