Abstract: A bias value associated with a sensor, e.g., a time-varying, non-zero value which is output from a sensor when it is motionless, is estimated using a ZRO-tracking filter which is a combination of a moving-average filter and a Kalman filter having at least one constraint enforced against at least one operating parameter of the Kalman filter. It achieves faster convergence on an estimated bias value and produces less estimate error after convergence. A resultant bias estimate may then be used to compensate the biased output of the sensor in, e.g., a 3D pointing device.

Abstract: An ergonomically enhanced electric power tool is disclosed that incorporates a new type of user grip and control system. This grip and control system is housed in a substantially rigid control-housing sheath, which provides enhanced leverage and control over the drilling process while reducing stress on the user's hand, wrist, and arm. The tool motor is disposed substantially in parallel with the user's wrist, but on a different plane, and eliminates the traditional “pistol” type of power-tool grip. The control-housing sheath contains a grip-controller assembly that allows the user to control most major drill operations within the gauntlet-like control-housing sheath. The inventive concepts described can be applied to myriad hand-held power tools, and a detailed example for a power drill is provided.

Abstract: An ergonomically enhanced electric power tool is disclosed that incorporates a new type of user grip and control system. This grip and control system is housed in a substantially rigid control-housing sheath, which provides enhanced leverage and control over the drilling process while reducing stress on the user's hand, wrist, and arm. The tool motor is disposed substantially in parallel with the user's wrist, but on a different plane, and eliminates the traditional “pistol” type of power-tool grip. The control-housing sheath contains a grip-controller assembly that allows the user to control most major drill operations within the gauntlet-like control-housing sheath. The inventive concepts described can be applied to myriad hand-held power tools, and a detailed example for a power drill is provided.