A direct pose feedback (DPF) control method applied to a DPF controlled machine is provided. The DPF control method includes a pose compensation control in addition to the position feedback control. The pose compensation control includes an initiation step, a reference system step, an actual pose calculation step and a position compensation step. The sum of the primary driving value and the compensation driving value is output to the driver of each of the motors. The advantage of the DPF control method is that the existing real-time position control loop in the controller can remain unchanged, while the pose compensation control is added to eliminate tool pose error resulted from geometric errors in the machine. The DPF controlled machine uses a pose measuring mechanism to measure the actual pose of the tool and to compensate the tool pose error. Hence, the DPF controlled machine is free of geometric errors.

A direct pose feedback (DPF) control method applied to a DPF controlled machine is provided. The DPF control method includes a pose compensation control in addition to the position feedback control. The pose compensation control includes an initiation step, a reference system step, an actual pose calculation step and a position compensation step. The sum of the primary driving value and the compensation driving value is output to the driver of each of the motors. The advantage of the DPF control method is that the existing real-time position control loop in the controller can remain unchanged, while the pose compensation control is added to eliminate tool pose error resulted from geometric errors in the machine. The DPF controlled machine uses a pose measuring mechanism to measure the actual pose of the tool and to compensate the tool pose error. Hence, the DPF controlled machine is free of geometric errors.

A method of calibrating a coordinate positioning machine is described. The machine is controlled into a pivot pose in which a target point associated with a moveable part of the machine and a pivot point associated with a fixed part of the machine are separated from one another by a known separation. An error value for that pose is determined based on the known separation and a separation expected for that pose from the existing model parameters of the machine. The machine is controlled into a plurality of different target poses, and for each target pose a separation between the target point and the pivot point is measured and an error value for that pose is determined based on the measured separation and a separation expected for that pose from the existing model parameters.

A method of calibrating a coordinate positioning machine is described. The machine is controlled into a pivot pose in which a target point associated with a moveable part of the machine and a pivot point associated with a fixed part of the machine are separated from one another by a known separation. An error value for that pose is determined based on the known separation and a separation expected for that pose from the existing model parameters of the machine. The machine is controlled into a plurality of different target poses, and for each target pose a separation between the target point and the pivot point is measured and an error value for that pose is determined based on the measured separation and a separation expected for that pose from the existing model parameters.

A device for measuring a path under load of a first part that is in motion relative to a second part. The device includes an active telescopic bar and a connector. The telescopic bar includes a scale to measure the length of the bar, a coupler to ball link at each end of the bar, and a force sensor to measure the force applied to the bar along its longitudinal axis. The connector links each end of the bar to the first and second part, respectively. The spatial components of the force applied to one of the connector are measured. A measuring method utilizing the device.

A method of calibrating a coordinate positioning machine is described. The machine is controlled into a pivot pose in which a target point associated with a moveable part of the machine and a pivot point associated with a fixed part of the machine are separated from one another by a known separation. An error value for that pose is determined based on the known separation and a separation expected for that pose from the existing model parameters of the machine. The machine is controlled into a plurality of different target poses, and for each target pose a separation between the target point and the pivot point is measured and an error value for that pose is determined based on the measured separation and a separation expected for that pose from the existing model parameters.

A device for measuring a path under load of a first part that is in motion relative to a second part. The device includes an active telescopic bar and a connector. The telescopic bar includes a scale to measure the length of the bar, a coupler to ball link at each end of the bar, and a force sensor to measure the force applied to the bar along its longitudinal axis. The connector links each end of the bar to the first and second part, respectively. The spatial components of the force applied to one of the connector are measured. A measuring method utilizing the device.

A method of calibrating a coordinate positioning machine is described. The machine is controlled into a pivot pose in which a target point associated with a moveable part of the machine and a pivot point associated with a fixed part of the machine are separated from one another by a known separation. An error value for that pose is determined based on the known separation and a separation expected for that pose from the existing model parameters of the machine. The machine is controlled into a plurality of different target poses, and for each target pose a separation between the target point and the pivot point is measured and an error value for that pose is determined based on the measured separation and a separation expected for that pose from the existing model parameters.