JP2015513093A - Coordinate measuring machine with removable accessories - Google Patents

Abstract

A portable articulated arm coordinate measuring machine for measuring the coordinates of an object in space is provided. The AACMM includes a base and an arm having a first end and a second end on opposite sides. The arm includes a plurality of connected arm segments, each arm segment including at least one position transducer for generating a position signal. Electronic circuitry receives position signals from at least one position transducer and provides data corresponding to the position of the measurement device. A non-contact measuring device is coupled to the first end, the device having an electromagnetic radiation transmitter and configured to determine a distance to the object based at least in part on the speed of light in the air. ing. A processor is configured to determine a three-dimensional coordinate of a point on the object in response to receiving the position signal and the distance to the object.

Description

  The present disclosure relates to a coordinate measuring machine, and more specifically, enables an accessory device that utilizes a transit time of flight for non-contact three-dimensional measurement to be connected to the coordinate measuring machine. The present invention relates to a portable joint arm coordinate measuring machine having a connector to be connected to a probe end of a coordinate measuring machine.

  Portable Articulated Arm Coordinate Measuring Machine (AACMM) is used in the manufacture and production of parts that need to quickly and accurately inspect the dimensions of the parts during the various stages of the manufacture or production (eg machining) of the parts. Widely used. The portable articulated arm coordinate measuring machine is a significant improvement over known stationary or fixed and costly measuring equipment that is relatively difficult to use, especially with respect to the time taken to measure the dimensions of relatively complex parts Is shown. Normally, a user of a portable articulated arm coordinate measuring machine simply guides the probe along the surface of the part or measurement object. Measurement data is recorded and provided to the user. In some cases, the data is provided to the user in a visual form, such as a three-dimensional (3D) format, on a computer screen. In other cases, the data is provided to the user in numerical form, for example, when measuring the diameter of a hole, “Diameter = 1.0034” is displayed on the computer screen.

  An example of a prior art portable articulated arm coordinate measuring machine is disclosed in US Pat. No. 5,402,582 ('582), assigned to the assignee of the present invention. The '582 patent discloses a 3D measurement system comprising a manually operated articulated arm coordinate measuring machine having a support base at one end and a measurement probe at the other end. A similar articulated arm coordinate measuring machine is disclosed in US Pat. No. 5,611,147 ('147) assigned to the assignee of the present invention. The '147 patent provides an arm with multiple features including an additional axis of rotation at the probe end, thereby providing either a 2-2-2 or 2-2-3 axial configuration (the latter In this case, it becomes a 7-axis arm).

  Three-dimensional surfaces can also be measured using non-contact techniques. One type of non-contact device, sometimes referred to as a laser line probe, emits laser light over a point or along a line. For example, an imaging device such as a charge coupled device (CCD) is placed adjacent to the laser to image the reflected light from the surface. The surface of the object being measured causes irregular reflection. The image on the sensor changes as the distance between the sensor and the surface changes. By knowing the relationship between the imaging sensor and the laser and the position of the laser image on the sensor, it is possible to measure points on the surface using triangulation.

  While existing coordinate measuring machines are suitable for their original purpose, there is a need for portable articulated arm coordinate measuring machines having the specific features of embodiments of the present invention.

  According to one embodiment of the present invention, a portable articulated arm coordinate measuring machine (AACMM) for measuring the coordinates of an object in space is provided. The AACMM includes a base and a manually positionable arm having a first end and a second end on opposite sides. The arm portion is rotatably coupled to the base and includes a plurality of connected arm segments, each arm segment including at least one position transducer for generating a position signal. The electronic circuit is configured to receive a position signal from at least one position transducer. The probe end is connected to the first end. A non-contact three-dimensional measuring device is connected to the probe end. The non-contact three-dimensional measuring device has an electromagnetic radiation transmitter and is configured to determine a distance to an object based at least in part on the speed of light in the air. A processor is electrically coupled to the electronic circuit and is responsive to receiving a position signal from the electronic circuit, and in response to receiving a distance from the non-contact 3D measuring device to the object, a three-dimensional point on the object. Configured to determine coordinates.

  According to one embodiment of the present invention, a method is provided for operating a portable articulated arm coordinate measuring machine for measuring the three-dimensional coordinates of an object in space. The method includes providing a manually positionable arm having opposite first and second ends, the arm including a plurality of connected arm segments; Each arm segment includes a step including at least one position transducer for generating a position signal. Electronic circuitry receives the position signal from the transducer. A non-contact three-dimensional measurement device having a controller electrically coupled to an electronic circuit is provided, the three-dimensional non-contact measurement device having an electromagnetic radiation transmitter and a sensor. Electromagnetic radiation is sent from the three-dimensional measuring device to the object. The reflected electromagnetic radiation is received by the sensor. The distance to the object is determined from the reflected electromagnetic radiation received by the sensor, in which case the distance is the speed of light in the air and the electromagnetic radiation travels from the electromagnetic radiation transmitter to the object and returns to the sensor. Based at least in part on the time to come.

  According to another embodiment of the present invention, another portable articulated arm coordinate measuring machine (AACMM) for measuring the three-dimensional coordinates of an object in space is provided. The AACMM includes a base and a manually positionable arm having a first end and a second end on opposite sides. The arm portion is rotatably coupled to the base and includes a plurality of connected arm segments, each arm segment including at least one position transducer for generating a position signal. An electronic circuit is provided that receives a position signal from at least one position transducer. A probe end is disposed between the measuring device and the first end and has an interface on one side. A contactless three-dimensional measuring device having a light source and an optical receiver is detachably connected to the interface. A non-contact 3D measurement device determines the distance to a point on an object based at least in part on the speed of light in the air and the time that the light from the light source travels from the light source to the object and returns to the optical receiver. Is configured to determine. A processor is electrically coupled to the electronic circuit and is configured to determine a three-dimensional coordinate of the point on the object based at least in part on the position signal received from the transducer and the determined distance.

  Referring to the drawings, representative embodiments are shown, but the drawings are not limiting with respect to the full scope of the disclosure, and components are numbered the same in several drawings. Has been.

1 is a perspective view of a portable articulated arm coordinate measuring machine (AACMM) having embodiments of various aspects of the invention therein. FIG. 1 is a perspective view of a portable articulated arm coordinate measuring machine (AACMM) having embodiments of various aspects of the invention therein. FIG. FIG. 2 is a block diagram of an electronic device used as part of the AACMM of FIG. 1 according to one embodiment. FIG. 2 is a block diagram of an electronic device used as part of the AACMM of FIG. 1 according to one embodiment. FIG. 2 is a block diagram of an electronic device used as part of the AACMM of FIG. 1 according to one embodiment. FIG. 2 is a block diagram of an electronic device used as part of the AACMM of FIG. 1 according to one embodiment. FIG. 2 is a block diagram of an electronic device used as part of the AACMM of FIG. 1 according to one embodiment. 3 is a block diagram illustrating detailed features of the electronic data processing system of FIG. 2 according to one embodiment. FIG. 3 is a block diagram illustrating detailed features of the electronic data processing system of FIG. 2 according to one embodiment. FIG. 3 is a block diagram illustrating detailed features of the electronic data processing system of FIG. 2 according to one embodiment. FIG. FIG. 2 is an isometric view of the probe end of the AACMM of FIG. 1. FIG. 5 is a side view of the probe end of FIG. 4 while the handle is connected. FIG. 5 is a side view of the probe end of FIG. 4 with a handle attached. FIG. 7 is an enlarged partial side view of the interface portion at the probe end of FIG. 6. FIG. 6 is another enlarged partial side view of the interface portion at the probe end of FIG. 5. FIG. 5 is an isometric view that is a partial cross-sectional view of the handle of FIG. 4. 2 is an isometric view of the probe end of the AACMM of FIG. 1 fitted with a non-contact distance measuring device. FIG. FIG. 11 is a schematic diagram of an embodiment in which the apparatus of FIG. 10 is an interferometer system. FIG. 11 is a schematic diagram of an embodiment in which the apparatus of FIG. 10 is an absolute rangefinder system. FIG. 11 is a schematic diagram of an embodiment in which the apparatus of FIG. 10 is a focus rangefinder. FIG. 11 is a schematic diagram of an embodiment in which the apparatus of FIG. 10 is a contrast focus rangefinder.

  Portable articulated arm coordinate measuring machines (“AACMM”) are used in a variety of applications to obtain measurements of objects. Embodiments of the present invention enable an operator to easily and quickly connect an accessory device that performs non-contact measurement of a three-dimensional object to a probe end of an AACMM using a structured projection. Provides the advantage of Embodiments of the present invention provide the further advantage of communicating data representing the distance to an object measured by an accessory. Embodiments of the present invention also provide the additional advantage of providing power and data communication for removable accessories without having external connections or wiring.

  1A and 1B are perspective views of an AACMM 100 according to various embodiments of the present invention, where the articulated arm is a type of coordinate measuring machine. As shown in FIGS. 1A and 1B, a typical AACMM 100 is a 6-axis or 7-axis joint measuring apparatus having a probe end 401 (FIG. 4), and the probe end 401 is an arm portion of the AACMM 100 at one end. A measurement probe housing 102 coupled to 104 is included. The arm portion 104 includes a first arm segment 106 coupled to the second arm segment 108 by a first group 110 of bearing cartridges (eg, two bearing cartridges). A second group 112 of bearing cartridges (eg, two bearing cartridges) couples the second arm segment 108 to the measurement probe housing 102. A third group 114 of bearing cartridges (eg, three bearing cartridges) couples the first arm segment 106 to a base 116 disposed at the other end of the arm portion 104 of the AACMM 100. Each group 110, 112, 114 of bearing cartridges provides multiple axes of articulation. The probe end 401 may also include a measurement probe housing 102 (eg, a cartridge that includes an encoder system that determines the movement of a measurement device such as the probe 118 within the rotation axis of the AACMM 100) having a shaft of the rotation axis of the AACMM 100. Good. In this embodiment, the probe end 401 rotates about an axis that passes through the center of the measurement probe housing 102. When using the AACMM 100, the base 116 is typically fixed to a workbench.

  Each bearing cartridge in each bearing cartridge group 110, 112, 114 typically houses an encoder system (eg, an optical angle encoder system). Each encoder system (ie, transducer) shows together the position of the probe 118 relative to the base 116 (and thus the position of the object being measured by the AACMM 100 in a particular reference system, such as a local or global reference system), respectively. The positions of the arm segments 106, 108 and corresponding groups of bearing cartridges 110, 112, 114 are shown. The arm segments 106, 108 may be made of a suitable rigid material, such as, but not limited to, a carbon composite material, for example. The portable AACMM 100 with 6 or 7 axes of articulation (ie, degrees of freedom) provides an arm portion 104 that can be easily handled by the operator while the operator desires within a 360 degree region around the base 116. This provides the advantage of allowing the probe 118 to be positioned at However, it should be understood that the description of arm portion 104 having two arm segments 106, 108 is for purposes of illustration and the claimed invention should not be so limited. The number of arm segments connected by the bearing cartridge of the AACMM 100 may be arbitrary (thus, more or less than 6 or 7 axes of articulation or degrees of freedom).

  The probe 118 is removably attached to the measurement probe housing 102 and the measurement probe housing 102 is connected to a group 112 of bearing cartridges. The handle 126 can be removed from the measurement probe housing 102 using, for example, a quick-connect interface. As described in more detail below, the handle 126 can be replaced with another device configured to provide a non-contact distance measurement of an object so that the operator can use the same AACMM 100 to make contact and non-contact. The advantage is that it makes it possible to make contact measurements. In the exemplary embodiment, probe 108 is a contact-type measuring device and is removable. The probe 118 may have various tips 118 that are in physical contact with the object to be measured, including, but not limited to, a ball-shaped, touch-sensitive, curved, elongated probe. In other embodiments, the measurement is performed by a non-contact device, such as, for example, an interferometer or an absolute distance measurement (ADM) device. In one embodiment, the handle 126 is replaced with a coded pattern projection scanner device using a quick connect interface. The removable handle 126 may be replaced with another type of measuring device to provide additional functionality. Examples of such measuring devices include, but are not limited to, one or more lights, temperature sensors, thermal scanners, barcode scanners, projectors, paint sprayers, cameras, and the like.

  As shown in FIGS. 1A and 1B, the AACMM 100 includes a removable handle 126 that provides the advantage of allowing accessories or functionality to be changed without removing the measurement probe housing 102 from the group 112 of bearing cartridges. . As described in more detail below with respect to FIG. 2, the removable handle 126 includes an electrical connector that allows power and data to be exchanged with corresponding electronics located on the handle 126 and probe end 401. May be included.

  In various embodiments, each group 110, 112, 114 of bearing cartridges allows the arm portion 104 of the AACMM 100 to move about multiple axes of rotation. As described above, each bearing cartridge group 110, 112, 114 has a corresponding encoder system, such as an optical angle encoder, disposed coaxially with the corresponding axis of rotation of the arm segments 106, 108, respectively. Including. The optical encoder system can perform, for example, rotational (swivel) or lateral (hinge) movement about the corresponding axis of each of the arm segments 106, 108, as described in more detail herein below. Detect and send a signal to the electronic data processing system in AACMM 100. Each raw encoder count is transmitted separately as a signal to the electronic data processing system, and the count is further processed into measurement data in the electronic data processing system. There is no need for a position calculator (eg, a serial box) separate from the AACMM 100 itself, as disclosed in US Pat. No. 5,402,582 ('582), assigned to the assignee of the present invention.

  Base 116 may include a mounting device or mounting device 120. The attachment device 120 allows the AACMM 100 to be removably attached to a desired location such as, for example, an examination table, machining center, wall, or floor. In one embodiment, the base 116 includes a handle portion 122 that provides a convenient location for an operator to hold the base 116 when moving the AACMM 100. In one embodiment, the base 116 further includes a movable cover 124 that, when folded, allows a user interface such as a display screen to be seen.

  According to one embodiment, the base 116 of the portable AACMM 100 includes two main components: data from various encoder systems within the AACMM 100, and other to support three-dimensional (3D) position calculations. A base processing system for processing data representing arm parameters, and an onboard operating system, a touch screen display, which allows a relatively complete measurement function to be implemented within the AACMM 100 without the need for connection to an external computer; And a user interface processing system including resident application software.

  The electronic data processing system within the base 116 includes encoder systems, sensors, and other peripheral hardware located remotely from the base 116 (eg, a non-contact distance measuring device that can be attached to a removable handle 126 on the AACMM 100). Can communicate with. Electronic devices that support these peripheral hardware devices or functions may be located in each of the bearing cartridge groups 110, 112, 114 within the portable AACMM 100.

  FIG. 2 is a block diagram of electronic equipment utilized in AACMM 100, according to one embodiment. The embodiment shown in FIG. 2A includes a base processor board 204 for implementing a base processing system, a user interface board 202, a base power board 206 for supplying power, a Bluetooth module 232, and a base tilt board 208. Including an electronic data processing system 210. User interface board 202 includes a computer processor for executing application software that performs user interfaces, displays, and other functions described herein.

  As shown in FIG. 2A, the electronic data processing system 210 is in communication with the encoder systems described above via one or more arm buses 218. In the embodiment shown in FIGS. 2B and 2C, each encoder system generates encoder data, an encoder arm bus interface 214, an encoder digital signal processor (DSP) 216, an encoder read head interface 234, and a temperature sensor. 212. Other devices such as a strain sensor may be attached to the arm bus 218.

  Also shown in FIG. 2D is probe end electronics 230 in communication with armbus 218. The probe end electronics 230 includes a probe end DSP 228, a temperature sensor 212, a handle / device interface bus 240 that connects to the handle 126 or non-contact distance measuring device 242 via a quick connect interface in one embodiment, and a probe interface. 226. The quick connect interface allows access by the handle 126 to the data bus, control lines, and power bus used by the non-contact distance measuring device 242 and other accessories. In one embodiment, the probe end electronics 230 is located in the measurement probe housing 102 of the AACMM 100. In one embodiment, the handle 126 can be removed from the quick connect interface, and the measurement can be performed by a non-contact distance measuring device 242 that communicates with the probe end electronics 230 of the AACMM 100 via the interface bus 240. In one embodiment, the electronic data processing system 210 is located at the base 116 of the AACMM 100, the probe end electronics 230 is located at the measurement probe housing 102 of the AACMM 100, and the encoder system comprises a group of bearing cartridges 110, 112, 114. The probe interface 226 is based on Maxim Integrated Products, Inc., which implements the 1-wire® communication protocol 236. Can be connected to the probe end DSP 228 by any suitable communication protocol including products sold by:

  FIG. 3A is a block diagram illustrating detailed features of the electronic data processing system 210 of the AACMM 100, according to one embodiment. In one embodiment, the electronic data processing system 210 is located at the base 116 of the AACMM 100 and includes a base processor board 204, a user interface board 202, a base power board 206, a Bluetooth module 232, and a base tilt module 208. .

  In the embodiment shown in FIG. 3A, base processor board 204 includes the various functional blocks shown in the figure. For example, the base processor function 302 is utilized to support the collection of measurement data from the AACMM 100 and receives raw arm data (eg, encoder system data) via the arm bus 218 and bus control module function 308. To do. The memory function 304 stores a program and static arm configuration data. The base processor board 204 also includes an external hardware option port function 310 for communicating with any external hardware device or accessory, such as a non-contact distance measuring device 242. Real-time clock (RTC) and log 306, battery pack interface (IF) 316, and diagnostic port 318 are also included in the functionality of the embodiment of base processor board 204 shown in FIG.

  The base processor board 204 also manages all wired and wireless data communications with external (host computer) and internal (display processor 202) devices. The base processor board 204 is connected to an Ethernet network via an Ethernet function 320 and a wireless local area network via a LAN function 322 (eg, using a clock synchronization standard such as the Institute of Electrical and Electronics Engineers (IEEE) 1588). (WLAN) and the ability to communicate with the Bluetooth® module 232 via the parallel serial communication (PSC) function 314. The base processor board 204 also includes a connection to a universal serial bus (USB) device 312.

  Base processor board 204 may process raw measurement data (e.g., encoder system counts) for processing into measurement data without requiring any pre-processing as disclosed in the '582 patent serial box described above. Send and collect temperature readings). Base processor 204 transmits the processed data to display processor 328 on user interface board 202 via RS485 interface (IF) 326. In one embodiment, the base processor 204 also transmits raw measurement data to an external computer.

  Next, looking at the user interface board 202 of FIG. 3B, the angle and position data received by the base processor is utilized by an application running on the display processor 328 to provide an autonomous measurement system within the AACMM 100. The Applications support functions such as, but not limited to, feature measurement, training and instructional images, remote diagnosis, temperature correction, control of various motion functions, connection to various networks, and display of measured objects May be executed by the display processor 328. Along with a display processor 328 and a liquid crystal display (LCD) 338 user interface (e.g., a touch screen LCD), the user interface board 202 has a secure digital (SD) card interface 330, a memory 332, a USB host interface 334, and diagnostics. It includes several interface options including a port 336, a camera port 340, an audio / video interface 342, a dial-up / cell modem 344, and a global positioning system (GPS) port 346.

  The electronic data processing system 210 shown in FIG. 3A also includes a base power board 206 having an environment recorder 362 for recording environmental data. The base power supply board 206 also supplies power to the electronic data processing system 210 using the AC / DC converter 358 and the battery charger control 360. The base power board 206 is based on an inter-integrated circuit (I2C) serial single-ended bus 354 and via a DMA serial peripheral interface (DSPI) 357. Communicate with. The base power board 206 is connected to a tilt sensor and radio frequency identification (RFID) module 208 via an input / output (I / O) extension 364 mounted on the base power board 206.

  Although shown as separate components, in other embodiments, all or some of these components may be physically located at a location different from the location shown in FIG. Alternatively, the functions may be combined in a manner different from that shown in FIG. For example, in one embodiment, base processor board 204 and user interface board 202 are combined into one physical board.

  4-9, the measurement probe housing 102 with a quick-connect mechanical and electrical interface that allows a removable and replaceable device 400 to be coupled to the AACMM 100. An exemplary embodiment of a probe end 401 having a is shown. In the exemplary embodiment, apparatus 400 includes a containment cover 402 that includes a handle portion 404 that is sized and shaped to be grasped by an operator's hand, such as, for example, a pistol handle. The containment cover 402 is a thin wall structure having a cavity 406 (FIG. 9). The cavity 406 is sized and configured to accommodate the controller 408. The controller 408 can be, for example, a digital circuit having a microprocessor or an analog circuit. In one embodiment, controller 408 is in asynchronous two-way communication with electronic data processing system 210 (FIGS. 2 and 3). The communication connection between the controller 408 and the electronic data processing system 210 may be wired (eg, via the controller 420), or a direct or indirect wireless connection (eg, Bluetooth or IEEE 802.11). Or a combination of wired and wireless connections. In the exemplary embodiment, the containment cover 402 is formed in two halves 410, 412 from, for example, an injection molded plastic material. The halves 410, 412 may be secured together by a fastener such as a screw 414, for example. In other embodiments, the containment cover halves 410, 412 may be secured together, for example, by adhesive or ultrasonic welding.

  The handle portion 404 also includes buttons or operating portions 416, 418 that can be manually actuated by an operator. The operation units 416 and 418 are connected to a controller 408 that transmits a signal to the controller 420 in the probe housing 102. In the exemplary embodiment, the operation units 416 and 418 perform the functions of the operation units 422 and 424 disposed on the opposite side of the probe housing 102 from the device 400. It should be understood that device 400 may have additional switches, buttons, or other controls that can be used to control device 400, AACMM 100, or vice versa. The device 400 may also include an indicator such as a light emitting diode (LED), a sound source, a meter, a display, or a meter. In one embodiment, the apparatus 400 may include a digital voice recorder that allows verbal comments to be left simultaneously with the measurement points. In yet another embodiment, the apparatus 400 includes a microphone that allows an operator to send a voice activation command to the electronic data processing system 210.

  In one embodiment, the handle portion 404 may be configured for use with an operator's hand or a specific hand (such as left or right handed). The handle portion 404 can also be configured to assist a disabled operator (such as an operator with a missing finger or an operator with a prosthetic hand). Furthermore, the handle portion 404 can be removed when the spatial gap is limited, and the probe housing 102 can be used alone. As described above, the probe end 401 may include the shaft of the rotation axis of the AACMM 100.

  The probe end 401 includes a mechanical and electrical interface 426 having a first connector 429 (FIG. 8) of the device 400 that cooperates with a second connector 428 of the probe housing 102. Connectors 428 and 429 include electrical and mechanical features that allow connection of device 400 to probe housing 102. In one embodiment, interface 426 includes a first surface 430 having a mechanical coupling 432 and an electrical connector 434 thereon. The containment cover 402 also includes a second surface 436 disposed proximate to the first surface 430 and stepped from the first surface 430. In the exemplary embodiment, second surface 436 is a planar surface that is stepped about 0.5 inches from first surface 430. This step provides a gap for the operator's finger when tightening or loosening a fastener such as collar 438. The interface 426 provides a relatively quick and stable electronic connection between the device 400 and the probe housing 102 without the need to align the pins of the connector and without the need for a separate cable or connector. provide.

  The electrical connector 434 extends from the first surface 430 and is electrically in two-way asynchronous communication with the electronic data processing system 210 (FIGS. 2 and 3), such as via one or more arm buses 218, for example. One or more connector pins 440 coupled to the. The bi-directional communication connection may be wired (eg, via armbus 218), wireless (eg, Bluetooth or IEEE 802.11), or a combination of wired and wireless connections. In one embodiment, electrical connector 434 is electrically coupled to controller 420. The controller 420 may communicate asynchronously with the electronic data processing system 210, such as via one or more arm buses 218, for example. The electrical connector 434 is arranged to provide a relatively quick and stable electronic connection with the electrical connector 442 of the probe housing 102. The electrical connectors 434 and 442 connect to each other when the device 400 is attached to the probe housing 102. The electrical connectors 434, 442 are each covered with metal that provides shielding from electromagnetic interference, protection of the connector pins, and pin alignment assistance during the process of mounting the device 400 to the probe housing 102. A connector housing may be included.

  The mechanical linkage 432 is provided between the device 400 and the probe housing 102 to support a relatively high precision application where it is preferable that the device 400 at the end of the arm 104 of the AACMM 100 is not misaligned or moved. Provides a relatively strong mechanical connection between. In general, any such movement can lead to an undesirable decrease in the accuracy of the measurement results. These desired results are achieved using various structural features of the mechanical attachment component of the quick connect mechanical electrical interface of embodiments of the present invention.

  In one embodiment, the mechanical linkage 432 includes a first protrusion 444 disposed at one end 448 (the leading edge or “frontmost” portion of the device 400). The first protrusion 444 may include a protrusion, notch, or sloped interface that forms a lip edge 446 extending from the first protrusion 444. The lip 446 is sized to be received in a groove 450 (FIG. 8) defined by a protrusion 452 extending from the probe housing 102. The first convex portion 444 and the groove 450 together with the collar 438, when the lip 446 is positioned in the groove 450, the longitudinal direction and the lateral direction when the apparatus 400 is mounted on the probe housing 102 using the groove 450. It should be understood that the coupling arrangement is configured to limit both directional movements. As described in more detail below, rotation of the collar 438 may be used to secure the lip 446 within the slot 450.

  On the opposite side of the first convex portion 444, the mechanical coupling portion 432 may include a second convex portion 454. The second protrusion 454 may have a notched lip edge with a protrusion or a sloped interface surface 456 (FIG. 5). The second convex portion 454 is arranged to engage a fastener related to the probe housing 102 such as a collar 438, for example. As will be discussed in more detail below, the mechanical linkage 432 provides a lift that protrudes from the surface 430 located near or around the electrical connector 434 that provides a fulcrum for the interface 426. (Figs. 7 and 8). This functions as a third of the three mechanical contacts between the device 400 and the probe housing 102 when the device 400 is attached to the probe housing 102.

  The probe housing 102 includes a collar 438 disposed on the same axis at one end. The collar 438 includes a threaded portion that can move between a first position (FIG. 5) and a second position (FIG. 7). By rotating the collar 438, the collar 438 can be used to secure or remove the device 400 without the need for external tools. As the collar 438 rotates, the collar 438 moves along a cylinder 474 that is relatively rough and squarely threaded. Such relatively large sized squares are threaded and the use of the outer surface provides a very large clamping force with minimal rotational torque. Furthermore, the coarse pitch of the cylinder 474 threads allows the collar 438 to be tightened or loosened with minimal rotation.

  To connect the device 400 to the probe housing 102, the lip 446 is inserted into the groove 450 and the device rotates the second ridge 454 toward the surface 458 as shown by the arrow 464 (FIG. 5). It is pivoted to do. As the collar 438 rotates, the collar 438 moves or translates in the direction indicated by arrow 462 to engage the surface 456. The movement of the collar 438 relative to the angled surface 456 pushes the mechanical connection 432 toward the raised surface 460. This helps to overcome potential problems of interface deformations or foreign objects on the surface of the interface that may prevent the device 400 from being firmly secured to the probe housing 102. Applying a force to the second protrusion 454 by the collar 438 pushes the lip 446 into the seat on the probe housing 102 while moving the mechanical connection 432 forward. As the collar 438 continues to be tightened, the second convex portion 454 applies pressure to the fulcrum while being pushed upward toward the probe housing 102. This applies pressure to the second protrusion 454, the lip 446, and the central fulcrum to reduce or eliminate the misalignment or swing of the device 400, resulting in a seesaw-type configuration. The fulcrum pushes directly on the bottom of the probe housing 102, while the lip 446 applies a downward force to the end of the probe housing 102. FIG. 5 includes arrows 462, 464 that indicate the direction of movement of the device 400 and collar 438. FIG. 7 includes arrows 466, 468, 470 indicating the direction of pressure applied within the interface 426 when the collar 438 is tightened. It should be understood that the step distance of the surface 436 of the device 400 provides a gap 472 (FIG. 6) between the collar 438 and the surface 436. The gap 472 allows the operator to grip the collar 438 more securely while reducing the risk of pinching fingers as the collar 438 is rotated. In one embodiment, the probe housing 102 is rigid enough to reduce or prevent deformation when the collar 438 is tightened.

  Embodiments of the interface 426 allow for proper alignment of the mechanical connection 432 and the electrical connector 434 and protect the electronics interface from the applied pressure, which pressure 438, lip 446 , And the clamping action of the surface 456. This provides the advantage of reducing or eliminating force damage to electrical connectors 434, 442 attached to circuit board 476 having soldered terminals. Embodiments are also advantageous over known approaches in that a user does not need a tool to connect or disconnect the device 400 to or from the probe housing 102. This allows the operator to manually connect the device 400 to the probe housing 102 and disconnect it from the probe housing 102 relatively easily.

  Thanks to the relatively large number of shielded electrical connections possible by the interface 426, a relatively large number of functions can be shared between the AACMM 100 and the device 400. For example, the device 400 may be controlled using switches, buttons, or other controls disposed on the AACMM 100, or vice versa. Further, commands and data may be transmitted from the electronic data processing system 210 to the device 400. In one embodiment, the apparatus 400 is a video camera that transmits recorded image data to be stored in the memory of the base processor 204 or to be displayed on the display 328. In another embodiment, the apparatus 400 is an image projector that receives data from the electronic data processing system 210. Also, the temperature sensor located in either AACMM 100 or device 400 may be shared by the other. It should be appreciated that embodiments of the present invention provide the advantage of providing a flexible interface that allows a wide variety of accessory devices 400 to be coupled to AACMM 100 quickly, easily, and reliably. In addition, the ability to share functionality between AACMM 100 and device 400 allows the size, power consumption, and complexity of AACMM 100 to be reduced by eliminating duplication.

  In one embodiment, the controller 408 may change the operation or function of the probe end 401 of the AACMM 100. For example, when the apparatus 400 is mounted and when the probe housing 102 is used alone, the controller 400 emits light of different colors, emits light of different intensity, or is turned on / off at different timings. The indicator light of the probe housing 102 may be changed to do any of the above. In one embodiment, apparatus 400 includes a ranging sensor (not shown) that measures the distance to an object. In this embodiment, the controller 408 may change the indicator light on the probe housing 102 to indicate to the operator how far the object is from the probe tip 118. This provides the advantage of simplifying the requirements of the controller 420 and allows for functional upgrades or improvements by adding accessory devices.

  Referring now to FIGS. 10-14, an apparatus 500 that enables non-contact measurement of an object is shown. In one embodiment, the device 500 is removably coupled to the probe end 401 via a coupling mechanism and interface 426. In another embodiment, the device 500 is integrally connected to the probe end 401. As will be described in more detail below, the device 500 is an interferometer (FIG. 11), absolute distance measurement (ADM) device (FIG. 12), focus meter (FIGS. 13 and 14), or other types of non-contact distance. It may be a measuring device.

  The apparatus 500 further includes a storage cover 501 having a handle portion 510. In one embodiment, the device 500 includes an interface 426 at one end that mechanically and electrically couples the device 500 to the probe housing 102 as described hereinabove. Interface 426 provides the advantage that apparatus 500 can be quickly and easily coupled to and removed from AACMM 100 without the need for additional tools. In another embodiment, the device 500 may be integrated within the probe housing 102.

  The apparatus 500 includes an electromagnetic radiation transmitter, such as a light source 502 that emits coherent or incoherent light, such as laser light or white light, for example. Light from the light source 502 is directed out of the device 500 toward the measurement object. The apparatus 500 may include an optical assembly 504 and an optical receiver 506. The optical assembly 504 may include one or more lenses, beam splitters, dichroic mirrors, quarter wave plates, polarizing optics, and the like. The optical assembly 504 splits the light emitted by the light source and directs a portion to an object, such as, for example, a retroreflector and a portion to the optical receiver 506. The optical receiver 506 is configured to receive the reflected light and redirected light from the optical assembly 504 and convert the light into an electrical signal. Both the light source 502 and the optical receiver 506 are coupled to the controller 508. The controller 508 may include one or more microprocessors, digital signal processors, memory, and signal conditioning circuitry.

  It should also be understood that the device 500 is substantially fixed with respect to the probe tip 118 such that the force on the handle portion 510 does not affect the alignment of the device 500 with respect to the probe tip 118. In one embodiment, the device 500 may have an additional operator (not shown) that allows an operator to switch acquisition of data from the device 500 and the probe tip 118.

  The apparatus 500 may further include operating units 512, 514 that can be manually activated by an operator to initiate operation and data acquisition by the apparatus 500. In one embodiment, optical processing to determine the distance to the object is performed by the controller 508 and the distance data is transmitted to the electronic data processing system 210 via the bus 240. In another embodiment, the optical data is transmitted to the electronic data processing system 210 and the distance to the object is determined by the electronic data processing system 210. Since the device 500 is coupled to the AACMM 100, the electronic processing system 210 can determine the position and orientation of the device 500 (via a signal from the encoder), and when combined with the distance measurement, It should be understood that it is possible to determine the X, Y, Z coordinates of an object relative to the AACMM 100.

  In one embodiment, the apparatus 500 shown in FIG. 11 is an interferometer. An interferometer is a type of rangefinder that emits a coherent beam such as a laser beam to a point on an object. In the exemplary embodiment, the object is, for example, an external retroreflector 516. The interferometer combines the return light and the reference beam light to measure changes in the distance of the object. By placing the retroreflector 516 at an initial position where the distance D is known, the distance D 'can also be determined when the retroreflector 516 moves to a new position. With a normal or incremental interferometer, the coherent light pattern is repeated for each half wavelength of the object point movement relative to the rangefinder, so the distance is determined by counting half wavelengths. The retroreflector 516 may be a spherically mounted retroreflector comprising a metal sphere with an embedded cube corner retroreflector. The cube corner retroreflector comprises three vertical mirrors that come together at a common vertex. In one embodiment, the apex is located at the center of the metal sphere. By holding the sphere in contact with the object, the distance to a point on the object surface can be measured with an interferometer. The retroreflector 516 may be another type of device that sends light back in parallel with the emitted light.

  In one embodiment, apparatus 500 is an incremental interferometer. The incremental interferometer has a measured distance D calculated using D = a + (n + p) * (lambda / 2) * c / n, where “a” is a constant and “n” is the movement of the target The integer of the counts revealed in “p” is the fractional part of the period (number of 0 to 1 corresponding to the phase angle of 0 to 360 degrees), “Lambda” is the wavelength of light in vacuum, “c "Is the speed of light in vacuum, and" n "is the refractive index of air at the wavelength of light 524 at the temperature, pressure, and humidity of the air through which light 524 passes. The refractive index is defined as the speed of light in a vacuum divided by the speed of light in the local medium (in this case air), so the calculated distance D is the speed of light in air “c / n”. It depends on. In one embodiment, the light 518 from the light source 502 passes through the optical interferometer 504 and travels to the remote retroreflector 516 and passes through the optical interferometer 504 and enters the optical receiver on the return path. The optical receiver is attached to the phase interpolator. The optical receiver and phase interpolator collectively include optics and electronics for decoding the return light phase and tracking the number of half-wavelength counts. Electronic equipment such as a phase interpolator in the articulated arm 100 or electronic equipment in an external computer determines the incremental distance that the retroreflector 516 has moved. The incremental distance traveled by the retroreflector 516 in FIG. 11 is D'-D. The distance D 'at any point in time can be determined, for example, by first finding the position of the retroreflector at a reference position that is a distance D from the reference point of the articulated arm CMM. For example, if a retroreflector is present in a spherically mounted retroreflector (SMR), the distance D ′ can be found by first placing the retroreflector 516 at a reference position, for example, , A magnetic nest configured to hold the SMR. Thereafter, the total distance D ′ can be determined using the reference distance as the value of “a” in the equations described hereinabove unless the light beam is destroyed between the light source 502 and the retroreflector 516. it can. The reference distance can be determined, for example, by measuring a reference sphere with the scanner held in various orientations. The reference distance can be determined by obtaining the coordinates of the reference sphere in a self-aligning manner.

  FIG. 11 shows an outgoing light beam 524 that travels parallel to the return beam 524B but is offset from the return beam 524B. In some cases, it is preferred that light 524 and 524B travel in the opposite direction but along the same path so that the light returns to itself. In this case, it is important to use a separation method so that the reflected light does not enter or destabilize the light source 520. One method of separating the laser from the return light is to place a Faraday isolator in the optical path between the light source 502 and the return light 524B.

  In one embodiment of the incremental interferometer, the light source 502 is a homodyne device so that the interferometer is a laser operating at a single frequency. In other embodiments, the device may be a heterodyne device, and the laser operates at at least two frequencies to produce two overlapping beams that are polarized and orthogonal. The light source 502 emits light 518 that is directed into the beam splitter 520. Here, the first portion of light 522 is reflected and sent to the optical receiver 506. The first portion of light 522 is reflected by at least one mirror 523 to direct the first portion of light to the optical receiver 506. In the exemplary embodiment, first portion 522 is reflected by a plurality of mirrors 523 and beam splitter 520. This first portion 522 is reference beam light used for comparison with return light or reflected light.

  The second portion of light 524 passes through the beam splitter 520 and is directed to the retroreflector 516. It should be understood that the optical assembly 504 may further include other optical components (not shown) such as, but not limited to, lenses, quarter wave plates, filters, and the like. The second portion of light 524 travels to the retroreflector 516, which reflects the second portion 524 back to the device 500 along a path 527 that is parallel to the emitted light. The reflected light returns through the optical assembly where it passes through the beam splitter 520 and is sent to the optical receiver 506. In the exemplary embodiment, the return light merges into the optical path to the optical receiver 502 that is common with the first portion 522 of light as it passes through the beam splitter 520. It is understood that the optical assembly 504 may further include additional optical components (not shown), such as an optical system that generates a rotation of the plane of polarization, between the beam splitter 520 and the optical receiver 506, for example. I want. In these embodiments, the optical receiver 506 may be comprised of a plurality of polarization sensitive receivers that allow a power normalization function.

  The optical receiver 506 receives both the first portion 522 and the second portion 524 of light. Since the two portions of light 522, 524 each have a different optical path length, the second portion 524 will have a phase shift when compared to the first portion 522 in the optical receiver 506. In embodiments where the apparatus 500 is a homodyne interferometer, the optical receiver 506 generates an electrical signal based on the change in intensity of the two portions 522, 524 of light. In embodiments where the apparatus 500 is a heterodyne interferometer, the receiver 506 can enable phase or frequency measurements using techniques such as, for example, a Doppler shift signal. In some embodiments, the optical receiver 506 may be, for example, a fiber optic pickup that transmits received light to a phase interpolator 508 or spectrum analyzer. In yet another embodiment, the optical receiver 506 generates an electrical signal and transmits the signal to the phase interpolator 508.

  In an incremental interferometer, it is necessary to track the change in the number of counts n (from the equations herein above). If the light beam is held in retroreflector 516, the counts may be tracked using optical elements and electronics in optical receiver 506. In another embodiment, another type of measurement is used, in which light from the distance meter is sent directly to the measurement object. The object may be metal and may, for example, diffusely reflect light so that only a relatively small amount of light is returned to the optical receiver. In this embodiment, the light returns directly to itself so that the return light substantially coincides with the outgoing light. As a result, it may be necessary to provide a means for reducing the amount of light sent back into the light source 502 with, for example, a Faraday isolator.

  One of the difficulties in measuring the distance to the diffusion target is that interference fringes cannot be counted. For the retroreflector target 516, it is known that the phase of the light changes continuously as the retroreflector moves away from the tracker. If the light beam is moved over the object, the phase of the return light may change discontinuously, for example when the light passes near the edge. In this case, it is desirable to use a type of interferometer known as an absolute interferometer. An absolute interferometer emits multiple wavelengths of light simultaneously, and the multiple wavelengths are configured to create a “composite wavelength”, for example, in millimeters. Absolute interferometers have the same accuracy as incremental interferometers, except that it is not necessary to count interference fringes for each half wavelength of movement. Measurements can be taken anywhere within the region corresponding to one synthetic wavelength.

  In one embodiment, the optical assembly 504 is a micro electro mechanical system (MEMS) that allows light from the absolute interferometer to be reflected back by the scanner and received again by the scanner to quickly measure the area. A steering mirror (not shown) such as a mirror may be included.

  In one embodiment, the apparatus may optionally include an image acquisition device such as a camera 529 used in combination with an absolute interferometer. Camera 529 includes a lens and a photosensitive array. The lens is configured to image an object point irradiated on the photosensitive array. The photosensitive array is configured to respond to the wavelength of light emitted by the absolute interferometer. By focusing on the position of the light imaged on the photosensitive array, the ambiguity range of the object point can be determined. For example, assume the absolute interferometer ambiguity range is 1 mm. In that case, if the distance to the target within 1 millimeter is known, there is no problem in finding the distance to the target using the interferometer. On the other hand, assume that the distance to the target within an ambiguity range of 1 millimeter is unknown. In one embodiment, a method for finding the distance to a target that is within the ambiguity range is to place the camera 529 near the ray exit point. The camera forms an image of scattered light on the photosensitive array. The position of the imaged light spot depends on the distance to the optical target, thereby providing a way to determine the distance to an object within the ambiguity range.

  In one embodiment, the distance measuring device uses coherent light (eg, a laser) in determining the distance to the object. In one embodiment, the apparatus changes the wavelength of the laser as a time function, eg, a linear time function. Part of the emitted laser light is sent to the photodetector, and another part of the emitted laser light toward the retroreflector is also sent to the detector. The light beam is optically mixed at the detector and an electrical circuit evaluates the signal from the photodetector to determine the distance from the rangefinder to the retroreflector target.

  In one embodiment, device 500 is an absolute distance meter (ADM) device. ADM devices typically use incoherent light and determine the distance to the object based on the time required to travel from the rangefinder to the target and back. ADM devices are usually less accurate than interferometers, but ADM offers the advantage of directly measuring the distance to an object rather than measuring the change in distance to the object. Thus, unlike an interferometer, an ADM does not require a known initial position.

  One type of ADM is the Time of Flight (TOF) ADM. In pulse time-of-flight ADM, the laser emits a pulse of light. Part of the light is sent to the object, scattered by the object, and picked up by a photodetector that converts the optical signal into an electrical signal. Another portion of the light is sent directly to the detector (or another detector) where it is converted to an electrical signal. The time dt between the leading edges of the two electrical pulse signals is used to determine the distance from the distance meter to the object point. The distance D is exactly D = a + dt * c / (2n), where a is a constant, c is the speed of light in vacuum, and n is the refractive index of light in air.

  Another type of ADM is a phase-based ADM. The phase-based ADM modulates the optical power of the emitted laser light by directly applying sinusoidal modulation to the laser. The modulation is applied as a sine wave or a square wave. The phase related to the fundamental frequency of the detected waveform is extracted. The fundamental frequency is the main frequency or the lowest frequency of the waveform. Typically, the phase with respect to the fundamental frequency sends light to a photodetector to obtain an electrical signal, condition the light (may include sending light through an amplifier, mixer, and filter), and an analog to digital converter Is used to convert the electrical signal to a digitized sample and then calculate the phase using a calculation method.

  The phase-based ADM has a measured distance D equal to D = a + (n + p) * c / (2 * f * n), where “a” is a constant, “n” and “p” are object points. The integer and fractional part of the “ambiguity range”, “f” is the modulation frequency, “c” is the speed of light in vacuum, and n is the refractive index. The quantity R = c / (2 * f * n) is an ambiguity range. For example, when the modulation frequency f = 3 gigahertz, the ambiguity range is about 50 mm from the above equation. The equation for obtaining “D” indicates that the calculated distance depends on the speed of light “c / n” in the air. As with absolute interferometers, one of the parameters that it is desirable to determine is the ambiguity range for the object being investigated. In order to measure the coordinates of the diffusing surface using the AACMM 100, the beam from the device 500 may be directed to an object that is several meters apart within a few milliseconds. If the ambiguity range is not determined, such a large change is likely to exceed the ambiguity range of the device, so the ADM remains unidentified of the distance to the object point.

  In one embodiment, the emitted light is modulated at multiple frequencies so that the ambiguity range can be determined in real time. For example, in one embodiment, four different modulation frequencies can be applied to the laser light simultaneously. The absolute distance to the target can be determined by calculating the phase for each of these four frequencies by well known means consisting of a sampling procedure and an extraction procedure. In another embodiment, fewer than 4 frequencies are used. Phase-based ADMs can be used in either the proximity range or the remote range. The modulation method and the processing method are also possible using another type of non-interferometric rangefinder. Such rangefinders are well known in the art and will not be described further.

  In one embodiment shown in FIG. 12, apparatus 500 includes light source 528, isolator 530, ADM electronics 546, fiber network 536, fiber emitter 538, and optionally beam splitter 540 and position detector 542. Is an ADM device. The light source 528 may be, for example, a laser such as a red or infrared laser diode. The laser light may be transmitted through an isolator 530 such as a Faraday isolator or an attenuator, for example. Isolator 530 may be a fiber coupled at the input and output ports. The ADM electronics 532 modulates the light source 528 by applying a radio frequency (RF) electrical signal to the laser input. In one embodiment, the RF signal is applied via a cable 532 that modulates the optical power of the light emitted by the laser in a sinusoidal fashion at one or more modulation frequencies. The modulated light passing through the isolator travels to the fiber network 536. Some of the light travels over the optical fiber 548 to the reference channel of the ADM electronics 546. Another portion of the light travels out of the device 500, is reflected by the target 516, and returns to the device 500. In one embodiment, target 516 is a non-cooperative target such as a diffuse reflective material such as aluminum or steel. In another embodiment, target 516 is a collaborative target such as, for example, a retroreflector target that returns most of the light back to apparatus 500. Light incident on the device 500 returns through the fiber emitter 538 and the fiber network 536 and enters the measurement channel of the ADM electronics 546 through the fiber optic cable 550. The ADM electronics 546 converts the reference light signal and the measurement light signal received from the optical fibers 548 and 550 into an electrical reference signal and an electrical measurement signal. These signals are processed in an electronic circuit to determine the distance to the target.

  In one embodiment, light from device 500 is sent to a retroreflector rather than a non-cooperative (diffusely scattering) target. In this case, a position detector 542 may be included to receive a small amount of light reflected by the beam splitter 540. The signal received by the position detector 542 may be used by the control system to cause the light from the device 500 to track the moving retroreflector 516. When a scattering target is used instead of a retroreflective target, the beam splitter 540 and the position detector 542 may be omitted.

  In one embodiment, the ADM device 500 incorporates a configuration as described in US Pat. No. 7,701,559 owned by the assignee of the present invention. It should be understood that both the interferometer device and the ADM device determine the distance to the object based at least in part on the speed of light in the air.

  Another type of distance meter is based on the focusing method. Examples of the focus distance meter include a color focus distance meter, a contrast focus distance meter, and an array sensing focus distance meter. For example, in an apparatus using a color focusing method as shown in FIG. 13, incoherent white light is generated by the light source 522. Due to the chromatic aberration of the lens 554 in the optical assembly, the light is focused on the “focal line” of the object 556 based on the wavelength of the light. As a result, different wavelength components of white light are focused at different distances. The distance to the object 556 may be determined using the spectrometer 557.

  Another type of focus rangefinder shown in FIG. 14 is a contrast focus device. In this embodiment, the distance to the object is determined by paying attention to the maximum contrast and the sharpness of the image. Focusing is achieved by moving the camera 558 along an axis in the direction of the object 560. When the position of maximum contrast is known, the object 560 is on the optical axis of the sensor 562 at a known distance. This known distance is predetermined during the calibration process.

  In one embodiment, the device 500 may be an array sensing focus rangefinder. In this type of device, the light source emits light through a lens and a beam splitter. Some of the light strikes the object, is reflected by the beam splitter, and travels to the photosensitive array. If the object under inspection is at the focal position of the light spot, the light on the photosensitive array will be very small. Thus, the AACMM 100 could always be used to capture 3D coordinates when the spot on the array was small enough.

  In yet another embodiment, the device 500 may be a conoscopic holography device. In this type of apparatus, the surface of an object is inspected with a laser point. The laser light is irregularly reflected on the surface to form a point light source. The light cone emanating from this point is magnified by the optical system. A birefringent crystal is disposed between two circular polarizers that split light into ordinary and extraordinary rays. After passing through the second polarizing lens, the two rays overlap to produce a holographic interference fringe pattern that can be acquired by a photosensitive sensor such as a CCD camera. The distance to the object is determined from the interference fringes by image processing.

  It should be understood that while focus and conoscopic holographic devices rely on the refractive index of light in air, the speed of light in air is independent of determining the distance of these devices.

  Although the invention has been described with reference to exemplary embodiments, various modifications can be made by those skilled in the art without departing from the scope of the invention, and equivalents may replace the components herein. It will be understood that this is possible. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Accordingly, it is intended that the invention not be limited to the specific embodiments discussed and disclosed as the best mode for carrying out the invention, ie, the invention is It is intended to include all embodiments that are within the scope of the claims. Furthermore, the use of terms such as first and second does not imply importance, and terms such as first and second are used to distinguish one element from another. Still further, terms such as “one” do not indicate a limitation of quantity, but indicate that there is at least one of the described elements.

Claims (26)

A portable articulated arm coordinate measuring machine (AACMM) for measuring the coordinates of an object in space,
The base,
A plurality of connected arm segments having a first end and a second end opposite the first end and capable of being manually positioned and rotatably coupled to the base Each arm segment includes at least one position transducer for generating a position signal; and
Electronic circuitry configured to receive the position signal from the at least one position transducer;
A probe end coupled to the first end;
A non-contact measurement device coupled to the probe end, comprising an electromagnetic radiation transmitter and configured to determine a distance to an object based at least in part on the speed of light in the air Equipment,
A processor electrically coupled to the electronic circuit in response to receiving the position signal from the electronic circuit and in response to receiving a distance from the non-contact measuring device to the object; A processor configured to determine a three-dimensional coordinate of the upper point.   The AACMM according to claim 1, wherein the non-contact three-dimensional measuring apparatus is an absolute interferometer.   The AACMM of claim 2, wherein the absolute interferometer comprises a camera adjacent to the transmitter.   The AACMM of claim 1, wherein the non-contact measurement device is a phase-based ADM device.   The AACMM of claim 1, wherein the non-contact measuring device is a pulse time-of-flight ADM device.   The AACMM according to claim 1, wherein the non-contact measuring device is detachably connected to the probe end.   The AACMM of claim 1, wherein the electromagnetic radiation transmitter is a laser.   The AACMM of claim 1, further comprising a contact measurement device coupled to the probe end.   The AACMM of claim 1, wherein the non-contact measurement device is removably coupled to the probe end. A method of operating a portable articulated arm coordinate measuring machine for measuring the three-dimensional coordinates of an object in space comprising:
Providing a manually positionable arm having opposite first and second ends, the arm including a plurality of connected arm segments, each arm segment Comprising at least one position transducer for generating a position signal;
Receiving the position signal from the transducer with an electronic circuit;
Providing a contactless measurement device having a controller electrically coupled to the electronic circuit, the contactless measurement device comprising an electromagnetic radiation transmitter and a sensor;
Sending electromagnetic radiation from the non-contact measuring device to the object;
Receiving reflected electromagnetic radiation at the sensor;
Determining a distance from the reflected electromagnetic radiation received by the sensor to the object, the distance comprising the speed of light in the air and the electromagnetic radiation from the electromagnetic radiation transmitter to the object. Steps based at least in part on the time to progress and return to the sensor;
Determining three-dimensional coordinates of a point on the object based at least in part on the position signal received from a transducer and the determined distance.   The method according to claim 10, wherein in the step of providing the non-contact measuring device, the non-contact measuring device is an absolute interferometer.   12. The method of claim 11, wherein in providing the non-contact measurement device, the absolute interferometer comprises a camera adjacent to the transmitter.   The method of claim 10, wherein in the step of providing the non-contact measuring device, the non-contact measuring device is a phase-based ADM device.   11. The method of claim 10, wherein in the step of providing the non-contact measuring device, the non-contact measuring device is a pulse time-of-flight ADM device.   The method of claim 10, wherein in the step of providing the non-contact measuring device, the non-contact measuring device is removably coupled to the first end. Providing a probe end coupled to the first end;
11. The method of claim 10, further comprising removably coupling the non-contact measurement device to the probe. In the step of providing the probe end, the probe end further includes a fastener and a first electrical connector electrically connected to the electronic circuit;
The method according to claim 16, wherein in the step of providing the non-contact measurement device, the non-contact measurement device further includes a connection portion and a second electrical connector electrically connected to the controller. Mechanically coupling the non-contact measuring device to the probe end using the coupling part and the fastener;
18. The method of claim 17, further comprising electrically coupling the first electrical connector to the second electrical connector.   The method of claim 10, wherein in the step of providing a non-contact measuring device, the electromagnetic radiation transmitter is a laser.   The method of claim 10, further comprising providing a contact measurement device coupled to the first end. A portable articulated arm coordinate measuring machine (AACMM) for measuring the three-dimensional coordinates of an object in space,
The base,
A manually positionable arm having first and second ends on opposite sides, rotatably coupled to the base and including a plurality of connected arm segments; An arm portion, each arm segment including at least one position transducer for generating a position signal;
Electronic circuitry for receiving the position signal from the at least one position transducer;
A probe end disposed between the measuring device and the first end, the probe end having an interface on one side;
A non-contact measurement device detachably coupled to the interface, comprising a light source and a light receiver, the speed of light in the air, and light from the light source travels from the light source to the object A non-contact measuring device configured to determine a distance to a point on the object based at least in part on a return time to the optical receiver;
A processor electrically coupled to the electronic circuit, wherein the three-dimensional coordinates of a point on the object are based at least in part on the position signal received from the transducer and the determined distance. AACMM comprising: a processor configured to determine.   The AACMM according to claim 21, wherein the non-contact measuring device is an absolute interferometer.   The AACMM of claim 22, wherein the absolute interferometer comprises a camera adjacent to the transmitter.   The AACMM of claim 21, wherein the non-contact measurement device is a phase-based ADM device.   The AACMM of claim 21, wherein the non-contact measurement device is a pulse time-of-flight ADM device.   The AACMM of claim 21, further comprising a contact probe coupled to the probe end.

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