Abstract: An analogue probe for use with a coordinate positioning machine. The analogue probe comprises a temperature actuator which can be modulated so as maintain the temperature of at least a part of the analogue probe at a substantially constant predetermined temperature.

Abstract: A method of determining the dimensions and location of a surface feature, for example a valve seat. The surface of the feature is measured, for example using a spiral scan path with a tactile probe and the multiple data points acquired from the scan are used to create a digitized image. The digitized image is fitted to a nominal image (e.g. CAD data) of the surface feature. The deviation of the digitized image from the nominal image is used to determine at least one of the dimensions, location and form deviation of the surface feature.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. The coordinate positioning apparatus is driven to provide relative movement between the member and the surface profile in a circular path and the scanning head is driven to move the surface sensing device about said one or more axes, such that the surface sensing device maintains a nominally constant lead angle. The motion of the coordinate positioning apparatus and scanning head is synchronous.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. The coordinate positioning apparatus is driven to provide relative movement between the member and the surface profile in a circular path and the scanning head is driven to move the surface sensing device about said one or more axes, such that the surface sensing device maintains a nominally constant lead angle. The motion of the coordinate positioning apparatus and scanning head is synchronous.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. The coordinate positioning apparatus is driven to provide relative movement between the member and the surface profile in a circular path and the probe head is driven to move the surface sensing device about said one or more axes, such that the surface sensing device maintains a nominally constant lead angle. The motion of the coordinate positioning apparatus and probe head is synchronous.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. A desired measurement profile on the surface which the surface sensing device will track and the desired motion of the orientation of the surface sensing device as the surface' sensing device follows the measurement profile are defined. This data is used to derive the required path of the relative motion between the member of the coordinate positioning apparatus and the surface, such that the surface sensing device prescribes a trajectory along the measurement profile.

Abstract: An analogue probe for use with a coordinate positioning machine. The analogue probe comprises a temperature actuator which can be modulated so as maintain the temperature of at least a part of the analogue probe at a substantially constant predetermined temperature.

Abstract: A method of determining the dimensions and location of a surface feature, for example a valve seat. The surface of the feature is measured, for example using a spiral scan path with a tactile probe and the multiple data points acquired from the scan are used to create a digitized image. The digitized image is fitted to a nominal image (e.g. CAD data) of the surface feature. The deviation of the digitized image from the nominal image is used to determine at least one of the dimensions, location and form deviation of the surface feature.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. The coordinate positioning apparatus is driven to provide relative movement between the member and the surface profile in a circular path and the probe head is driven to move the surface sensing device about said one or more axes, such that the surface sensing device maintains a nominally constant lead angle. The motion of the coordinate positioning apparatus and probe head is synchronous.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. A desired measurement profile on the surface which the surface sensing device will track and the desired motion of the orientation of the surface sensing device as the surface' sensing device follows the measurement profile are defined. This data is used to derive the required path of the relative motion between the member of the coordinate positioning apparatus and the surface, such that the surface sensing device prescribes a trajectory along the measurement profile.