Abstract: Disclosed is a method of moving an articulating mechanism (22,410) for a measuring device, comprising the steps of: releasing two bodies (14,16, 410a,410b) which form the articulating mechanism allowing relative movement thereof; moving one of the bodies with respect to the other until a desired position is reached; and re-constraining the two bodies so they are relatively fixed, perhaps as part of a locking process, characterised in that relative movement prior to re-constraining at the desired position occurs under particular conditions. The particular conditions including moving from the same direction; and stopping, slowing down or maintaining the condition at a position adjacent to the desired position. Also disclosed is a method of positioning an articulating mechanism (22,410) for a measuring device which is controlled by a potentiometer and a controller (11) for a measuring device.

Abstract: A touch trigger probe incorporates piezoelectric sensors 50, whose outputs are processed by an interface circuit. The interface circuit discriminates between signals generated from the piezoelectric sensors 50 as a result of machine vibration and those generated as a result of a genuine measurement event, by the use of a timing circuit 90. The timing circuit 90 compares the time intervals (t.sub.1 -t.sub.2);(t.sub.2 -t.sub.3) between attainment of first 1.sub.1 and second 1.sub.2, and second 1.sub.2 and third 1.sub.3 output signal levels from the sensor 50, and upon the basis of this comparison validates (or rejects) measurements made with the probe. Additionally, the interface determines whether measurements made with the probe are taken upon the basis of outputs generated by the sensors 50 due to a shock wave in the stylus 24 of the probe, or as a result of strain in the stylus 24; as an alternative, measurements may be made only on the basis of strain.

Abstract: A touch trigger probe includes a hybrid integrated circuit (58). On this circuit are provided both kinematic support elements (28) for supporting a deflectable stylus (14) in a precise rest position, and sensing elements (40) for detecting contact between the stylus (14) and a workpiece. Embodiments are also disclosed in which the kinematic support elements are provided on a silicon chip, e.g. by micro-machining.

Abstract: Disclosed is a three dimensional coordinate measuring machine which is used to measure a workpiece. The machine has a probe containing a piezoelectric crystal which is capable of detecting the shockwave generated when the probe stylus contacts the surface of the workpiece, in order to provide a trigger signal. In order to reduce the risk of the piezoelectric crystal not triggering satisfactorily upon receipt of this shockwave, the workpiece is vibrated so that immediately upon contact the vibrations travel up the probe stylus to trigger the piezoelectric crystal. The vibrations are introduced by a vibration transducer which is bolted to the bed of the coordinate measuring machine.

Abstract: A probe (12) is connected to an interface circuit (10). The probe (12) has two different types of contact sensors, namely a piezo electric sensor and an electro-mechanical switching sensor. The trigger signal from the piezo electric sensor is detected by circuits (34,36,38,40) while that from the switching sensor is detected by a comparator (32). The signals are mixed in a mixer (42) to produce a single output trigger signal. A monostable (48) and latch (50) discriminate which sensor produced the output signal, making use of the inherent time delay between the two sensor signals. Circuits (24,26,28) determine if a conventional switching probe has been connected instead of the probe (12). If so, a transistor (T4) varies the power supply to the probe, and gates (30,33) switch in a comparator (18) in place of the comparator (32).

Abstract: Detection of a pattern feature in a two dimensional signal e.g. as produced by scanning a linear array of detectors, is performed by apparatus 20 (FIG. 3) comprising an M.times.N array 21 of serial input shift registers 40 in which the signal, digitized to binary level samples and on M channels, is stored. Sampling and input occur at timing intervals controlled by timing means 29, previous samples being shifted one stage through the registers. Pattern features each comprising a binary level pattern formed on an M.times.N element map of the array and comprising only one element per row, are encoded as sets of M binary address words defining shift register addresses in M.log.sub.2 N-bit template words stored in ROM 23'. A ROM address register 33' points to a ROM location and extracts a template word on bus 25 which comprises M.log.sub.2 N lines so that all the address words are extracted in parallel. A 1-out of-N data selector connected to parallel outputs of each shift register is addressed by its own log.sub.

Abstract: The probe has a piezo-electric sensor (22A) for determining initial contact of a stylus (16) with a workpiece (4). It also has a kinematic support (18) made up of confronting electrical contacts (19, 20) which are connected to indicate displacement of the stylus from a rest position and correct reseating on the kinematic support. The sensor (22A) and the electrical contacts (19, 20) are connected to an electrical circuit (24) within the probe. The circuit (24) has only two terminals connecting it to an external interface (9), which both receives the signals from and supplies power to the sensor (22A) and the contacts (19, 20). This enables the receipt of a signal from the contacts (19, 20) to provide a fail-safe backup to the signal from the sensor (22A) and to indicate correct reseating of the probe, while maintaining the interface (9) compatible with prior art probes having only one workpiece-engagement sensing arrangement with two terminals.

Abstract: A modular panel system consists of a plurality of panels. Each panel carries at least one and preferably two pivotal connection devices. Each pivotal connection device has thereon a hook-like or latch-like member which can fit into a slot to releasably connect one panel to an adjacent panel. A particular design of double axis hinge is also disclosed, which serves as the pivotal connection device.

Abstract: A touch trigger probe incorporates piezoelectric sensors 50, whose outputs are processed by an interface circuit. The interface circuit discriminates between signals generated from the piezoelectric sensors 50 as a result of machine vibration and those generated as a result of a genuine measurement event, by the use of a timing circuit 90. The timing circuit 90 compares the time intervals (t1-t2);(t2-t3) between attainment of first 11 and second 12, and second 12 and third 13 output signal levels from the sensor 50, and upon the basis of this comparison validates (or rejects) measurements made with the probe. Additionally, the interface determines whether measurements made with the probe are taken upon the basis of outputs generated by the sensors 50 due to a shock wave in the stylus 24 of the probe, or as a result of strain in the stylus 24; as an alternative, measurements may be made only on the basis of strain.

Abstract: Disclosed is a method of moving an articulating mechanism (22,410) for a measuring device, comprising the steps of: releasing two bodies (14,16, 410a,410b) which form the articulating mechanism allowing relative movement thereof; moving one of the bodies with respect to the other until a desired position is reached; and re-constraining the two bodies so they are relatively fixed, perhaps as part of a locking process, characterised in that relative movement prior to re-constraining at the desired position occurs under particular conditions. The particular conditions including moving from the same direction; and stopping, slowing down or maintaining the condition at a position adjacent to the desired position. Also disclosed is a method of positioning an articulating mechanism (22,410) for a measuring device which is controlled by a potentiometer and a controller (11) for a measuring device.