RT info:eu-repo/semantics/article T1 A kalman filter implementation for precision improvement in low-cost GPS positioning of tractors A1 Gómez Gil, Jaime A1 Ruiz González, Rubén A1 Alonso García, Sergio A1 Gómez Gil, Francisco Javier K1 Kalman filter K1 Agricultural vehicles K1 Global Positioning System (GPS) K1 Vehicle guidance K1 Sensor data fusion K1 33 Ciencias Tecnológicas AB Low-cost GPS receivers provide geodetic positioning information using the NMEA protocol, usually with eight digits for latitude and nine digits for longitude. When these geodetic coordinates are converted into Cartesian coordinates, the positions fit in a quantization grid of some decimeters in size, the dimensions of which vary depending on the point of the terrestrial surface. The aim of this study is to reduce the quantization errors of some low-cost GPS receivers by using a Kalman filter. Kinematic tractor model equations were employed to particularize the filter, which was tuned by applying Monte Carlo techniques to eighteen straight trajectories, to select the covariance matrices that produced the lowest Root Mean Square Error in these trajectories. Filter performance was tested by using straight tractor paths, which were either simulated or real trajectories acquired by a GPS receiver. The results show that the filter can reduce the quantization error in distance by around 43%. Moreover, it reduces the standard deviation of the heading by 75%. Data suggest that the proposed filter can satisfactorily preprocess the low-cost GPS receiver data when used in an assistance guidance GPS system for tractors. It could also be useful to smooth tractor GPS trajectories that are sharpened when the tractor moves over rough terrain. PB MDPI SN 1424-8220 YR 2013 FD 2013 LK https://uvadoc.uva.es/handle/10324/57820 UL https://uvadoc.uva.es/handle/10324/57820 LA eng NO Sensors, 2013, vol. 13, n. 11, p. 15307-15323 NO Producción Científica DS UVaDOC RD 12-sep-2024