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Integrating a 10g Pulse Laser Rangefinder for Long-Distance Drone Target Measurement

When building custom payloads for infrastructure inspection, power line monitoring, or search and rescue (SAR), adding target ranging capabilities often introduces a tough engineering trade-off: weight versus range.

Most low-altitude obstacle sensors (like standard phase-shift or optical flow LiDARs) max out at 30m–50m under sunlight. On the other hand, conventional laser rangefinders that reach 1km+ often weigh between 80g and 150g, putting severe strain on small 2-axis/3-axis brushless gimbal motors and cutting battery endurance.

Recently, I’ve been testing the TS1224 pulse laser rangefinder module, and its form factor makes it uniquely suited for lightweight UAV payloads. Here is a breakdown of its hardware profile, bench tests, and integration workflow.

1. Hardware Specifications & Footprint

The TS1224 is an OEM pulse time-of-flight (pToF) module designed specifically for integration where size and weight are strict constraints:

Because the module is bare-board and weighs only 10 grams, it can be mounted directly on the camera plate without requiring larger gimbal motors or bulky counterweights.

2. Mounting and Optical Boresighting

When coupling the TS1224 with a zoom camera or thermal core:

• Dual-Lens Clearance: The module features dedicated transmitting and receiving apertures (13.4mm profile). Ensure your 3D-printed shroud does not clip the optical cone to prevent internal beam backscatter.

• Co-Axial Calibration: At 1000 meters, an angular error of just $0.1^\circ$ shifts the laser pulse by $1.75\text{ m}$. Align the module's optical axis to the camera crosshair using a collimator or by zeroing in on a high-contrast target at a known distance (e.g., 200m–500m) before flight.

• Vibration Damping: Secure the module using M2 nylon screws with soft silicone o-rings to isolate the optical sensor from high-frequency motor harmonics ($200\text{Hz} - 400\text{Hz}$).

3. Wiring & Companion Computer Telemetry Loop

The module operates on standard 3.3V TTL UART logic, making it straightforward to pipe distance data into an onboard companion computer (Raspberry Pi CM4, Nvidia Jetson) or directly into a telemetry port:

[TS1224 Module]   ├── VCC (3.3V DC)  ├── GND  ├── TX ──────> RX [Companion Computer / ESP32 / Pixhawk TELEM]  └── RX <────── TX [Trigger Commands]

Data Handling Workflow:

1. Triggering: The host controller sends standard HEX/ASCII ranging commands over UART at 2Hz–5Hz.

2. MAVLink Encapsulation: The returned distance frame is parsed and mapped into DISTANCE_SENSOR or custom MAVLink telemetry packets.

3. Geo-Location Math: By combining the UAV’s current GPS coordinates, barometric altitude, gimbal pitch/yaw gimbal angles, and the TS1224's true slant distance ($d$), the companion computer calculates the exact target location using simple spherical trigonometry:

4. Summary & Verification

If you are developing custom gimbal payloads for utility inspection, wildlife observation, or long-range monitoring, switching to a 10g pulse module like the TS1224 laser rangefinder module solves the payload weight penalty without compromising on kilometer-class measurement.

What methods are you currently using to sync target slant distance with Ground Control Station (QGC / Mission Planner) overlays? Let’s discuss your payload setups below!