METHOD OF CONTROLLING AN INTELLIGENT ASSIST DEVICE

A method of controlling a powered manipulator (10) is disclosed. The powered manipulator (10) includes at least one motor (12), at least one force sensor (14) on a manual control handle (16) and a microprocessor (18) combined with the plurality of the force sensors (14) for controlling a powered manipulator (10) within physical limits of a workspace. The method comprises the steps of the operator imparting a force on the control handle (16), sensing the direction and magnitude of the force with the plurality of force sensors (14) and sending the force data to the microprocessor (18), processing the force data from the plurality of force sensors (14) with the microprocessor (18) to create movement commands for the powered manipulator (10) and moving the powered manipulator (10) in response to the movement commands from the microprocessor (18). An adaptive gain feature proportions powered manipulator movement commands relative to force imparted by an operator on the control handle (16) and can be relative to dynamic motion states. The microprocessor (18) is programmed for establishing virtual constraints to limit the movement of the powered manipulator (10) within a virtual workspace thereby preventing the operator from moving the powered manipulator (10) to at least some of the mechanical limits. Modifying the powered manipulator movement commands in relation to the virtual constraints assists the operator in guiding the powered manipulator (10) to a specific point within the virtual workspace.