URM04 Ultrasonic Distance Sensor (4-500cm, RS485)

The URM04 Ultrasonic Distance Sensor is an industrial-grade ranging module designed for reliable spatial detection over an RS485 bus. Built for robotics platforms, automation systems, and makers, it allows scalable multi-node networking across long cable runs in electrically noisy environments.

Multi-node RS485 networking

The module communicates via an RS485 serial interface, allowing up to 32 ultrasonic sensors to operate simultaneously on a single bus. It features configurable device addresses and baud rates, connecting easily to microcontroller platforms using standard RS485 adapters or shields.

Wide-range acoustic distance measurement

Using a 40 kHz acoustic signal, the sensor accurately measures distances from 4 cm up to 500 cm with a 1 cm resolution. This wide detection span makes it well-suited for autonomous vehicle navigation, boundary monitoring, and real-time obstacle avoidance.

Defined acoustic beam angle

The sensor features a focused beam pattern designed for reliable echo detection and spatial orientation. This directional acoustic profile provides consistent boundary detection for mobile robotics and automated equipment.

Integrated temperature compensation

An on-board 12-bit temperature sensor provides ambient readings directly over the serial interface. These readings allow host systems to apply temperature compensation algorithms to maintain accurate distance calculations in fluctuating environments.

Compact hardware and package contents

Operating at 5V across a temperature range of -10°C to +70°C, the compact 34x51 mm board weighs just 30 g. Each unit includes a dedicated wire with a 4-pin JST connector for straightforward wiring.

Downloads & documentation

• Product wiki (DFRobot)