# US 2018/0023946 A1 · Laser gauge for robotic calibration and monitoring > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0023946 A1 - Document ID: US20180023946A1 - Status: Published application - Kind: A1 - Application number: 15/549,485 - Filed: 2016-02-12 - Published: 2018-01-25 - Earliest claimed: 2015-02-13 - Assignees: Think Surgical, Inc. - Applicants: Think Surgical, Inc. - Inventors: Gibson ELLIOT - Web page: https://patentgrep.com/patent/US20180023946A1 ## CPC - G01B 11/2433: {for measuring outlines by shadow casting} - A61B 34/20: Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis - A61B 34/32: operating autonomously - B25J 9/1692: {Calibration of manipulator} - G01B 11/002: {for measuring two or more coordinates} - A61B 17/1668: {for the upper femur (A61B17/164 takes precedence)} - A61B 34/30: Surgical robots - A61B 2017/00725: {Calibration or performance testing} - A61B 2034/2057: {Details of tracking cameras} - A61B 2090/0812: {indicating loosening or shifting of parts of an instrument, signaling maladjustment of parts} - G05B 2219/45117: Medical, radio surgery manipulator - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract A contactless, and accurate device and methods of use thereof are provided to calibrate and verify the calibration of a robotic arm and associated attachments. The device uses a laser gauge for calibrating and subsequently verifying the calibration of the robotic arm, digitizer, or robotic tools. An optical transmitter, in communication with an optical receiver is fixed nearly perpendicular to a second optical transmitter in communication with a second optical receiver that form two optical micrometers that are offset a small distance, forming a small gap, d, to create a measuring void having two distinct non-intersecting measurement planes. One measurement plane measures the position and size of an object in a first axis direction and the other measurement plane measures the position and size of an object in a second axis direction. The position and size of an object is measured within the measuring void in both axial directions. ## Claims ### Claim 1 A laser gauge for calibration comprising: a first micrometer in communication with a first receiver; and a second micrometer in communication with a second receiver, said first micrometer being offset from said second micrometer to create a measurement void with two non-intersecting measurement planes in a space defined between said first micrometer and said first receiver and between said second micrometer and said second receiver. ### Claim 2 (depends on 1) The laser gauge of claim 1 wherein said two non-intersecting measurement planes comprise a first plane that measures a first position and a first size of an object in a ‘y’ axis direction and a second plane that measures a second position and size of the object in a ‘x’ axis direction; and wherein the position and a second size of the object is measured within the measuring void in both the ‘x’ axis direction and ‘y’ axis direction. ### Claim 3 (depends on 1) The laser gauge of claim 1 wherein said first micrometer and said second micrometer are optical transmitting devices. ### Claim 4 (depends on 1) The laser gauge of claim 1 wherein said first micrometer and said second micrometer utilize at least one of ultrasound, magnetic, or other forms of electromagnetic radiation. ### Claim 5 (depends on 1) The laser gauge of claim 1 wherein said first receiver and said second receiver are detection devices comprising at least one of photodiodes, CCD cameras, CMOS cameras, magnetic field sensor, or transducers. ### Claim 6 (depends on 1) The laser gauge of claim 1 further comprising a casing to house said first micrometer and said second micrometer for attachment to a robot, where a set of coordinates of said measuring void is known with respect to a coordinate frame of said robot. ### Claim 7 (depends on 1) The laser gauge of claim 1 further comprising at least one amplifier connected to at least one of said first micrometer and said second micrometer in communication with a robot. ### Claim 8 (depends on 7) The laser gauge of claim 7 wherein said robot is configured as an autonomous or semi-autonomous robotic system either for medical or industrial applications. ### Claim 9 (depends on 7) The laser gauge of claim 7 wherein said robot is programmed to preform mathematical operations to obtain a set of information about the position, size, orientation, velocity, acceleration of a robotic arm and an associated robotic tool. ### Claim 10 (depends on 1) A method for verifying calibration of a robotic arm with the laser gauge of claim 1 comprising: performing an initial calibration of said robotic arm; passing an end effector of said robotic arm through said measurement void at least once; recording and storing from said first micrometer and said second micrometer a position of said end effector within said measuring void; and using the recorded position of said end effector from said initial calibration procedure as a comparison tool to verify the robotic arm calibration in a subsequent calibration procedure. ### Claim 11 (depends on 1) A method for verifying calibration of a robotic arm with the laser gauge of claim 1 comprising: performing an initial calibration of said robotic arm; passing said end effector of said robotic arm through said measurement void three times to obtain three measured positions of said end effector; calculating and storing a set of side lengths and a set of angles between the three measured positions in three dimensional space; and using the stored set of side lengths and the set of angles from said initial calibration procedure as a comparison tool to verify the robotic arm calibration in a subsequent calibration procedure.