DGPS Gaucho

GPS Gaucho is a GPS Navigating Autonomous Vehicle. This is a project from a student team at Bradley University as a part of their curriculum. This project aims at building a control system for an autonomous vehicle using DGPS. DGPS stands for differential GPS. The underlying principle behind DPGS is that any two receivers that are relatively close together will experience similar atmospheric errors.

The Autonomous vehicle Gaucho is capable of identifying its current position and upon receiving a new location, calculates how to reach the new location and drive there. The DGPS system consists of two GPS units which are capable of acting as either GPS base stations or clients and a wireless 232 link between them. Here one of the GPS receivers is mounted on the base station whose position is fixed and the coordinates of this point is known in prerequisite. Another GPS receiver is mounted on Gaucho. By programming the GPS receivers to correctly produce or interpret DGPS data, a fixed location can be made with accuracy to enable the vehicle to stay in a relatively narrow drive path.

Here, the navigation control is done by an embedded device known as E-box. E-box is a small computer that runs on Windows CE. By using wireless-232 connection, the receiver on Gaucho receives correction data from the base station. Also, the E-box receives commands from a remote user using 802.11 wireless network.

The functioning of the autonomous navigator begins when the E-box communicates with the GPS receiver to determine if a differential fix can be made. In case the fix cannot be made, the system goes in standby mode and can only receive control commands from the manual remote controller or waits for a fix to be made. But if a valid differential fix is made, then the system will begin to accept position commands to move to a new location. On the basis of the new position the system then calculates the movements required to reach to the new position.