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Autonomous Robotics · Computer Vision · Embedded Systems

Autonomous Vision-Based Litter Collection Rover

A three-person senior project (EE 460/463/464) at Cal Poly San Luis Obispo: a rover that detects, approaches, and collects ground-level litter without human input.

Role Autonomy, motor control, embedded integration, and CAD / 3D-printed parts
Timeline September 2025 – June 2026
Team Three engineers
ROS 2 STM32L4A6ZG Jetson Orin Nano YOLO LiDAR SLAM EKF Theta* Pure Pursuit Mecanum Drive

What the system achieved.

0.033 m Mean cross-track error during nominal path following
0.059 m Mean cross-track error while avoiding obstacles
100% Collection success rate for plastic bottles
~12,700 Training images behind the YOLO litter detector

How it works.

The rover integrates autonomy, computer vision, embedded real-time control, mecanum-wheel omnidirectional mobility, and a two-degree-of-freedom robotic arm to detect, approach, and collect small ground-level litter such as bottles, wrappers, and paper fragments.

Two-layer compute architecture

Perception, SLAM, and path planning run on an NVIDIA Jetson Orin Nano under ROS 2. Real-time motor control and odometry run on an STM32L4A6ZG microcontroller. Splitting the system this way keeps the hard real-time control loop deterministic while leaving the compute-heavy perception stack free to run at its own cadence.

Perception and navigation

A YOLO-based detector trained on roughly 12,700 images locates litter in the RGB-D camera stream and projects each detection into the map frame. A custom Theta* planner generates paths to each target, and a pure-pursuit controller tracks them while an EKF fuses wheel odometry with LiDAR-based localization.

Mechanical platform

The robot is built on a multi-level aluminum frame with a 3D-printed collection ramp, machined sensor mounts, and custom electronics housings. The completed platform weighs approximately 42 lb.

The build, the data, and the system running.

Completed LitterBot prototype on grass, showing the aluminum frame, mecanum wheels, depth camera mast, LiDAR, and 3D-printed collection ramp.
The completed prototype, with integrated drive, collection, sensing, and control subsystems.
Six-panel plot of autonomy path tracking: XY planned versus actual path, cross-track error over time, heading error, cross-track error versus path position, and commanded linear and angular velocities.
Path-tracking performance during a live autonomy run: planned versus actual trajectory, cross-track and heading error, and commanded velocities.
System wiring diagram for the rover, showing the Jetson and STM32, motor drivers, sensors, and power distribution.
System wiring — the Jetson and STM32 domains, motor drivers, sensing, and power distribution.
LitterBot Command Center interface showing live YOLO litter detections with confidence scores and distances, a LiDAR scan, odometry readouts, and serial traffic between the Jetson and STM32.
The Command Center monitoring an autonomous run — live YOLO detections with range estimates, LiDAR returns, odometry, and Jetson/STM32 serial traffic.

Autonomous runs.

Two-item collection trajectories, recorded from both the robot's own interface and from the floor.

Run 1 — two-item trajectory with an obstacle, live.
The same run from the Command Center interface.
More recorded runs

Go deeper.

The full EE 460/463/464 report covers requirements, mechanical and electrical design, the software architecture, and the complete test data behind the results above.