RTK GNSS for Robot Dogs

Lidar and leg odometry drift over long outdoor routes. RTK GNSS gives an absolute position to 0.6 cm + 0.5 ppm, so the robot returns to the same checkpoint on every round and each reading is geotagged on the site map. Indoors or underground, the robot relies on its other sensors until it regains a view of the sky.

Yes, but heading accuracy depends on antenna spacing. Eview receivers give 0.15° at 1 m; on a robot with a shorter baseline the heading is less precise but still free of magnetic disturbance from motors. The HB51 adds an RM3100 magnetometer, and the HBEV322 includes a QMC5883L compass.

The HB52 box receiver measures just 48 × 35 × 12.6 mm. The HBEV322 smart antenna is the simplest install, because receiver, antenna and compass share one housing with a single GH1.25 connector. Pair box receivers with the EV210 antenna, which is 27.5 mm in diameter and IP67.

When the robot leaves a building or tunnel, multi-constellation tracking and RTK initialisation in about 7 s let it regain centimetre positions quickly. RAIM+ flags unreliable measurements near walls and doorways, so the navigation stack can keep relying on lidar or odometry until the GNSS solution is trustworthy again.

Eview receivers output standard NMEA and Septentrio SBF over UART, and the HB52 also over USB-C, so they connect to typical onboard computers on legged robots. RTK corrections are accepted in RTCM v3 format from an NTRIP caster, a CORS network or a local base station.