# US 12,001,224 B1 · Autonomous vehicle calibration > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,001,224 B1 - Document ID: US12001224B1 - Status: Granted - Kind: B1 - Application number: 17/707,457 - Filed: 2022-03-29 - Granted: 2024-06-04 - Earliest claimed: 2022-03-29 - Assignees: Amazon Technologies, Inc. - Applicants: Amazon Technologies, Inc. - Inventors: Adam Joseph Greenbaum; Stephen Charles Paschall - Web page: https://patentgrep.com/patent/US12001224B1 ## CPC - G05D 1/0297: {by controlling means in a control room} - G05D 1/0246: {using a video camera in combination with image processing means} - G06Q 10/0877: {by inventory control or reporting using inventory tracking or counting} - G07C 5/008: {communicating information to a remotely located station (transmission systems for measured values G08C)} - G07C 5/0808: {Diagnosing performance data (testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005)} - B65G 1/0492: {with cars adapted to travel in storage aisles} - G06Q 10/08744: {by distributed inventory management} - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - G06Q: INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR - G07C: TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE - B65G: TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS (packaging B65B; handling thin or filamentary materials, e.g. paper sheets or thread, B65H; cranes B66C; portable mobile or lifting or hauling appliances, e.g. hoists, B66D; devices for lifting or lowering goods for loading or unloading purposes, e.g. fork-lift trucks, B66F9/00; emptying bottles, jars, casks, barrels or similar containers, not otherwise provided for, B67C9/00; delivering or transferring liquids B67D; filling or discharging vessels for liquefied, solidified or compressed gases F17C; pipe-line systems for fluids F17D) ## Abstract An inventory management system can include a fleet of mobile drive units. The mobile drive units can detect, using a sensor, calibration data associated with a calibration fixture. The calibration of the sensors can be updated based on the calibration data. The calibration data for the fleet of mobile drive units can be used determine a correction factor. The correction factor can be applied to the fleet of mobile drive units to further update the calibration of the sensors. ## Claims ### Claim 1 An inventory handling system, comprising: a calibration region positioned within a warehouse environment, the calibration region comprising a calibration position marker and a calibration fixture; a fleet of mobile drive units, the fleet of mobile drive units having a plurality of mobile drive units each comprising: a propulsion system selectively operable to position the mobile drive unit in the calibration region; and one or more sensors configured to detect data associated with the calibration fixture; and a management module operable to: instruct a first mobile drive unit of the plurality of mobile drive units to move to the calibration position marker; instruct the first mobile drive unit to detect, using a first sensor, first calibration data associated with the calibration fixture; update calibration of the first sensor based on the first calibration data; instruct a second mobile drive unit of the plurality of mobile drive units to move to the calibration position marker; instruct the second mobile drive unit to detect, using a second sensor, second calibration data associated with the calibration fixture; update calibration of the second sensor based on the second calibration data; receive the first and second calibration data associated with the calibration fixture; and using a collective set of calibration data that includes at least the first and second calibration data, implement a fleet-wide update to the calibration of the one or more sensors of each of the plurality of mobile drive units including the first and second sensors. ### Claim 2 (depends on 1) The inventory handling system of claim 1, wherein the fleet of mobile drive units comprises greater than 30 mobile drive units. ### Claim 3 (depends on 1) The inventory handling system of claim 1, wherein the first calibration data includes a position, an electromagnetic field intensity, an electromagnetic field orientation, a color, or a texture of the calibration fixture. ### Claim 4 (depends on 1) The inventory handling system of claim 1, wherein the calibration position marker comprises a fiducial or an alignment pin. ### Claim 5 (depends on 1) The inventory handling system of claim 1, wherein the first sensor or the second sensor comprises a camera. ### Claim 6 (depends on 1) The inventory handling system of claim 1, wherein the management module is further operable to determine a fleet-wide correction factor based on the collective set of calibration data, and wherein the fleet-wide update to the calibration of the one or more sensors of each of the plurality of mobile drive units is based on the fleet-wide correction factor. ### Claim 7 (depends on 1) The inventory handling system of claim 1, wherein updating the calibration of the first sensor comprises comparing the first calibration data with an expected value. ### Claim 8 A system comprising: a calibration fixture; a fleet of mobile drive units, the fleet of mobile drive units having a plurality of mobile drive units, each of the mobile drive units comprising a sensor configured to detect data associated with the calibration fixture; and a management module operable to: instruct a subset of the fleet of mobile drive units including at least two of the mobile drive units of the plurality of mobile drive units to detect, using a sensor, calibration data associated with the calibration fixture; instruct each of the subset of the fleet of mobile drive units to update calibration of the sensor of the mobile drive unit based on the calibration data; receive, from the subset of the fleet of mobile drive units, the calibration data associated with the calibration fixture; generate a correction factor for the fleet of mobile drive units based on calibration data; and update calibration of the sensors of the plurality of mobile drive units based on the correction factor. ### Claim 9 (depends on 8) The system of claim 8, wherein, the management module is further operable to, prior to instructing the subset of the fleet of mobile drive units to detect the calibration data, instruct the mobile drive units to sequentially move to a calibration position in a calibration region. ### Claim 10 (depends on 8) The system of claim 8, wherein the calibration fixture comprises a calibration target coupled with a support, the support being independent from the plurality of mobile drive units. ### Claim 11 (depends on 8) The system of claim 8, wherein the sensor comprises a camera, lidar, radar, a proximity sensor, an impact sensor, a color sensor, a magnetic sensor, an electrical sensor, a brightness sensor, a spectrometer, a photometer, or a cliff sensor. ### Claim 12 (depends on 8) The system of claim 8, wherein at least one of the mobile drive units comprises a coupling system configured to engage with an inventory holder. ### Claim 13 (depends on 8) The system of claim 8, wherein the subset of the fleet of mobile drive units includes at least 100 mobile drive units. ### Claim 14 A method of calibrating a mobile drive unit, the method comprising: instructing a fleet of mobile drive units having a plurality of mobile drive units to sequentially move to a calibration position; instructing each of the mobile drive units of the fleet of mobile drive units to detect, using at least one sensor while at the calibration position, calibration data associated with a calibration fixture so that the plurality of mobile drive units collectively generate a plurality of calibration data; instructing each of the mobile drive units to update calibration of the at least one sensor based on the calibration data detected by the respective at least one sensor; receiving the plurality of calibration data associated with the calibration fixture; and updating, based on the plurality of calibration data, calibration of the sensors of the fleet of mobile drive units. ### Claim 15 (depends on 14) The method of claim 14, wherein the fleet of mobile drive units are sequentially moved to the calibration position based on predetermined time. ### Claim 16 (depends on 14) The method of claim 14, wherein the calibration data comprises a position, an orientation, an electromagnetic field intensity, an electromagnetic field orientation, a texture, or a color associated with the calibration fixture. ### Claim 17 (depends on 14) The method of claim 14, wherein updating the calibration of the sensors comprises generating a correction factor for the fleet of mobile drive units based on the calibration data. ### Claim 18 (depends on 17) The method of claim 17, wherein generating the correction factor for the fleet of mobile drive units comprises: calculating, using a management module, the correction factor for the fleet of mobile drive units; and sending the correction factor to the fleet of mobile drive units for updating the calibration of the sensors of the fleet of mobile drive units. ### Claim 19 (depends on 14) The method of claim 14, wherein instructing each of the fleet of mobile drive units to update the calibration of the at least one sensor comprises comparing the calibration data with an expected value. ### Claim 20 (depends on 14) The method of claim 14, further comprising instructing the fleet of mobile drive units to move around a warehouse environment using the sensors to detect objects in the warehouse environment.