Abstract: One aspect of the present invention comprises a coordinate measurement apparatus that includes an articulated arm having a first end, a second end, and plurality of jointed arm segments therebetween, each arm segment including at least one position transducer. A measurement probe assembly is coupled to the second end of the arm. The measurement probe assembly comprises a first joint providing a first axis of rotation between the second end of the arm and a body of the measurement probe assembly. An encoder includes an encoder housing and an encoder shaft. The encoder housing is configured to rotate about a second axis with respect to the encoder shaft, which is rigidly coupled to the body. A probe is rigidly coupled to the encoder shaft. A measurement device is coupled to the encoder housing such that the measurement device rotates about a second axis with respect to the probe.

Abstract: An automated coordinate measuring system comprising a measuring arm used for acquisition of geometry data that incorporates an exoskeletal structure resilient to physical perturbations including thermal changes and vibrations which may affect coordinate data acquisition. The system may be adapted to a portable platform allowing for convenient positioning and alignment of the measuring arm in a wide variety of environments.

Abstract: A single-scale, single-drive coordinate measuring machine that compensates for hysteresis error caused by friction at the non-driven end of the bridge. The coordinate measuring machine is calibrated to estimate hysteresis effects at one or more distances from the scale. Measurements of workpieces are adjusted based on the calibration data and the distances of the carriage from the scale at the point of the measurements. The scale and the drive system may be positioned on opposite guideways.