1. Field
Embodiments of the present invention relate to the enhancement of vehicle guidance systems. More particularly, the invention relates to correcting global navigation satellite system (GNSS) data using the measured or simulated attitude of a vehicle.
2. Related Art
A global navigation satellite system (GNSS), such as the global positioning system (GPS), is an electronic satellite navigation system which permits users to determine their position with respect to the Earth. Global positioning may be determined with a GNSS receiver which detects and decodes signals from a number of satellites orbiting the Earth. The signals from each of these satellites indicate the position of the satellite and the time at which the signals were sent. GNSS receivers may calculate latitude, longitude, and altitude based on satellite signals. This information is often used in vehicle guidance systems to guide a vehicle and direct it to perform certain tasks at a particular position. For example, an agricultural vehicle may be guided to a precise position by a GNSS receiver and commanded to drop a seed at that particular position.
Discrepancies may arise between the position information provided to the guidance system by the GNSS receiver and the actual ground position of the vehicle. Particularly, when the vehicle is on an incline, the calculated latitude and longitude position of the GNSS receiver may not be the same as the actual latitude and longitude ground position of the vehicle. These discrepancies can cause a vehicle guidance system utilizing GNSS information to inaccurately guide and instruct the vehicle, because the guidance system assumes that the GNSS receiver latitude and longitude position is the same as the vehicle ground position.
Accordingly there is a need for a method of correcting position information provided to the vehicle guidance system by GNSS that does not suffer from the problems and limitations of the prior art.