In this project, we are required to design a Turtlebot system to navigate a disaster zone maze, detect heat signals through an opaque acrylic wall, and deploy flares in a 2-4-2 pattern as a signal that the bot has reached its targets. The Turtlebot will operate without line-following capabilities and it will only be relying on sensors to navigate and perform its tasks. There will also be an added challenge, which requires the robot to scale a ramp using a 2D LiDAR.
The Maze Zone consists of 4 parts:
- Start Zone: This is where the Turtlebot 3 will be deployed at the start of every mission.
- Randomized Maze Zone: Obstacles will be randomly placed to obstruct navigation of the Turtlebot. The Turtlebot must not run into any of the obstacles during navigation.
- Survivor Zone: This is where a heat source will be placed. The Turtlebot will have to locate a heat source in this zone and commence the flare firing sequence of 2-4-2s pattern. There are 3 Survivor Zones in the Maze Zone, with the 3rd Survivor Zone being optional to detect.
- Ramp Zone: Connected to the 3rd Survivor Zone, the Turtlebot has to scale a ramp to access the 3rd Survivor Zone. This section is optional.
The maze zone will have the following dimensions labeled in the figure shown below:
| Mission Requirements | Project Deliverables |
|---|---|
| Traverse Map Autonomously | System shall use mapping techniques to create a map of maze environment |
| Navigate through Maze autonomously | System shall have capability for obstacle detection and avoidance during navigation and traversal |
| Identify heat sources | System shall have capability for detecting presence of heat soources |
| Navigate towards heat sources | System shall have capability for identifying location and bearing of heat sources and navigate towards heat sources |
| Launch ping pong balls near heat sources | System shall have capability for launching 3 ping pong balls in a 2-4-2 delay pattern for each survivor, for a maximum of 3 survivors with 9 balls |
| Recognise visited heat sources | System shall recognise heat sources that it has visited and not launch ping pong balls at the same survivor |
| Mission Requirements | Functional Requirements |
|---|---|
| Traverse Map Autonomously | System shall use Simultaneous Localization and Mapping to create a map of maze environment |
| Navigate through Maze autonomously | System shall utilise developed map to promptly detect obstacles and navigate around them to ensure smooth traversal. |
| Identify heat sources | System shall use IR Camera to detect presence of heat soources |
| Navigate towards heat sources | System shall have capability for identifying location of heat sources via temperature data from IR Camera and localisation data from SLAM to navigate towards heat sources |
| Launch ping pong balls near heat sources | System shall have capability for launching 3 ping pong balls in a 2-4-2 delay pattern for each survivor, for a maximum of 3 survivors with 9 balls |
| Recognise visited heat sources | System shall use location data to recognise heat sources that it has visited and not launch ping pong balls at the same survivor |
| Category | System Requirement |
|---|---|
| Performance | System shall accomplish the entire mission, including calibration of IR sensors, generation of SLAM map, within a time limit of 25 minutes. |
| Reliability | System shall operate reliably under various environmental conditions, including different maze configurations and lighting conditions. System shall be resilient to sensor noise and external disturbances. |
| Safety | System shall prioritise safety during operation to prevent collisions with obstacles and map elements. |
| Scalability | System shall be designed with scalability in mind to accommodate future enhancements or modifications. System shall be capable of adapting to changes in maze layouts or task requirements. |
| Usability | System shall have a user-friendly interface for easy setup, operation, and monitoring by human operators. |
| Accuracy | System shall achieve high accuracy in map generation, obstacle detection, and task execution. System shall minimise errors in localization and navigation to ensure precise performance. |
| Maintainability | System shall be designed for ease of maintenance and repair. System shall allow for quick diagnosis and replacement of any faulty components. |
| Power Efficiency | System shall optimise power usage to prolong battery life by employing energy-efficient algorithms and hardware components. |
| Constraint | Description |
|---|---|
| Power Supply Limitations | The robot must operate within constraints imposed by the power source, such as the battery capacity and voltage requirements. |
| Sensor and Actuator Limitations | The selection and integration of sensors and actuators are constrained by factors such as cost, availability, and compatibility with the robot operating platform - ROS2 |
| Processing Power and Memory | The onboard processing capabilities and memory resources of the robot system component (Raspberry Pi) are limited, affecting the complexity and efficiency of algorithms. |
| Environmental | Environmental factors such as ambient temperatures may affect sensor performance, navigation accuracy, and reliability. |
| Cost | The development and deployment of the robot system are constrained by a budget limitation of $80. Cost-effective solutions and resource prioritization are essential. |
Building upon the Turtlebot frame, we utilise an IR Camera to identify heat sources in the maze and a spring launcher mechanism actuated by servos to launch the ping pong balls upon detection and navigation to the survivor.
| Technical Components | Details |
|---|---|
| Model | TurtleBot3 Burger ICBM V1.2 |
| Software Version | 1.4.7 |
| Weight | 1606.63g |
| Battery Capacity | Lithium polymer 11.1V 1800mAh / 19.98Wh |
| Max Runtime | 1.5 – 2 hours |
| Charging Time | ~2.5 hours |
| Purpose | 1. To autonomously navigate the maze and avoid obstacles 2. Successfully find 3 heat signatures 3. Launches ping pong balls at predetermined intervals when heat signature found |