Orchard worker localisation relative to a vehicle using radio ranging and trilateration

摘要: Safe navigation of labour-aiding robots in commercial orchards will rely on accurate and continuous worker localisation. In this work, an ultra-wideband radio-based system localises a via trilateration four range measurements between antennas vehicle antenna carried the worker's belt. Performance results are presented from inside ‘work zones’ around vehicle, open space orchard. At walking speed space, when body placement allowed full line-of-sight (LOS) belt antennas, position estimate availability was 99.7% distance root mean square error (DRMS) 57.9 cm. Completely blocked LOS resulted signal outages unacceptable performance (11.1% availability; 819.7 cm DRMS). orchard, full-LOS similar to that open-space: 99.3% 63.4 cm DRMS bound. Orchard trees enabled multipath propagation, so blocked-LOS far better than open-space (60.2% 123.6 cm Antenna motion effects were studied orchard experiments without interference. Motion introduced non-collocation errors (individual ranges measured at slightly different positions); 1.6 2.2 times larger respective static errors. all 95th percentiles almost twice as large Sporadic could be addressed by two filtering. The indicate radio ranging offers practicable approach localisation relative nearby operating slow speeds.