Project
| # | Title | Team Members | TA | Documents | Sponsor |
|---|---|---|---|---|---|
| 91 | Automatic Bike Collision Prevention System |
Charlie Wang Nathan Zhu Rahul Nayak |
Frey Zhao | design_document1.pdf proposal1.pdf |
|
| # Automatic Bike Collision Prevention System Team Members: - Rahul Nayak (rn8) - Charlie Wang (cgwang3) - Nathan Zhu (nyzhu2) # Problem Active pathways like campus sidewalks create high risk scenarios for cyclists and passerby due to oblivious pedestrians and distracted riding. Traditional bicycle bells are reactive rather than proactive, requiring both the cyclist to recognize a potential collision and react by ringing the bell, and pedestrians to acknowledge the bell and move out of the way. The total time to prevent collision can be lengthened if the cyclist’s reaction time was not a consideration. As such, there is a need for an automated alert system that is able to identify and distinguish potential collision hazards before they occur. # Solution We will create a handlebar-mounted safety system using three mmWave radar sensors to act as a peripheral vision of sorts. The sensors will be set up such that we have a center sensor, and left and right sensors. The system performs spatial gating, where detections transitioning from peripheral radar sectors into the forward sector are classified as hazards, while detections only in the peripheral radar sectors are ignored. We estimate a time to collision depending on the current distance detected and the distance from past readings, and ring the bell at different volumes accordingly. # Solution Components ## Subsystem 1: Power Provide regulated power and system status feedback. Components: - Li-ion 18650 Battery: High capacity power source. - Buck-Boost Converter: Stable 5V/3.3V regulation. - Status LEDs: Indicators to indicate if the system is on, sensitivity level, and if an object is detected. - Sensitivity Potentiometer: Allows the rider to adjust the magnitude threshold for different environments. ## Subsystem 2: Radar Sensor Array Function: Detect object distance. Components: - Three HLK-LD2410 24GHz mmWave Radar Modules - Configuration: 1 center (0°), 2 side angled (30°) - To create distinct sensors, small 3D printed shields will be set to limit field of view and prevent cross-talking. - This triangular configuration allows for section-based filtering. - Due to limited UARTs on the ESP32, the radars should be checked one at a time in a very fast, cyclical manner, which would also help prevent crosstalking. ## Subsystem 3: Processing Function: Filter noise and determine collision likeliness. Components: - ESP32 Microcontroller: UART connection with Radar sensors - Magnitude thresholding: Ignore low energy reflections such as from pavement or small non-collision objects. - Time-To-Collision algorithm: Estimate how long it will take until a collision occurs. ## Subsystem 4: Alert System Function: Create a gradually audible ringing sound depending on the expected collision time. Components: - Piezo Buzzer (PS1240): Use Pulse Width Modulation to increase beep frequency - Three alert stages # Criterion For Success The project will be considered successful if all criteria below are met: - Range performance: Reliably detect objects from 5 meters away. - Low latency: Detection to audio output is less than 150ms. - Form factor: Device is compact enough to mount on handlebars. - False-positive mitigation: Thresholding prevents alarm from triggering for ground objects and other non hazards. - Peripheral vision: Device is able to detect objects in peripheral vision and keep track of these objects moving into the sight of the center sensor. - Battery life: Battery should last at least 8 hours on a single charge. |
|||||