Patent ID: 8116909

Claim:
An x-y robotic motion control system comprising: a controller; a first rail; a second rail spaced from the first rail wherein the first and second rails are substantially parallel to one another; a gantry having a first end movable along the first rail and a second end movable along the second rail; a first motor operably coupled to one of the first and second rails to displace the gantry along the one of the first and second rails, wherein the first motor is operably coupled to the controller; a payload movable along the gantry; a position sensor disposed to measure the position of the payload along the gantry; a first encoder configured to detect the first end of the gantry with respect to the first rail; a second encoder configured to detect the second end of the gantry with respect to the second rail; and wherein the position sensor and the first and second encoders are coupled to the controller and wherein the controller is configured to calculate a position of the payload as a function of signals from the position sensor and the first and second encoders.