OBJECT RECOGNITION And DISTANCE MEASUREMENT Using Raspberry Pi 5 And Hailo-8L AI

Imagine a vehicle cruising at 54 kilometres per hour, roughly the speed of an object moving 0.5 metres per frame at 30 frames per second (0.5 × 30 × 3.6 = 54 km/hr).

- SOMNATH BERA AND REON SAMANTA

Mounted on the vehicle's roof is a compact, high-performance vision system built around a Raspberry Pi 5 board and a Hailo-8L AI accelerator. This real-time setup detects objects ahead and estimates their distances from the vehicle. When an object enters a predefined safety zone, the system can instantly issue warnings or activate emergency braking, enhancing both situational awareness and reaction time.

Built using an AI Accelerator HAT on a Raspberry Pi 5, the system operates as a production-grade AI platform capable of running at a minimum of 30 frames per second. Designed for vehicle mounting, it continuously scans the road, identifies objects in real time, and calculates their distances. These live readings are displayed on the terminal. If any object crosses a predefined proximity threshold, the system may trigger alerts via GPIO pins. Although the alert mechanism is straightforward to implement, it remains unbuilt in the current version. The components required for assembling the system are listed in the Bill of Materials table. Fig. 1 shows the authors' working prototype.

Connection and mounting

The AI accelerator can be mounted on top of the Raspberry Pi, as shown in Fig. 2. Note that since the AI HAT fully covers the main processor, the Raspberry Pi 5 tends to heat up significantly. To prevent overheating, it is strongly recommended to use an additional cooling method. In this system, only a specific fixed-type cooler fits within the narrow space available once the AI HAT is mounted. The complete setup and its individual components are shown in Fig. 2. The Raspberry Pi 5 must also be powered by a high-quality 5V, 4A power adaptor to maintain stable performance.