# US 10,502,656 B1 · Servo apparatus supporting self-propelled vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,502,656 B1 - Document ID: US10502656B1 - Status: Granted - Kind: B1 - Application number: 15/364,040 - Filed: 2016-11-29 - Granted: 2019-12-10 - Earliest claimed: 2014-06-03 - Applicants: Garth L Magee - Inventors: Garth L Magee - Web page: https://patentgrep.com/patent/US10502656B1 ## CPC - G01M 9/02: Wind tunnels - G01M 17/007: Wheeled or endless-tracked vehicles (G01M17/08 takes precedence) - G01M 9/06: Measuring arrangements specially adapted for aerodynamic testing - G01M 17/0074: {Details, e.g. roller construction, vehicle restraining devices} - G01M 17/0076: {Two-wheeled vehicles} - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR ## Abstract A servo-controlled vehicle-supporting apparatus maintaining an unrestrained and freely self-propelled vehicle longitudinally stationary thereon. When employed inside a wind tunnel, the power transferred through groundward contact with the vehicle wheels can be directly measured, thereby indicating the propulsive power required to overcome total drag forces on a vehicle as if driving on a roadway. ## Claims ### Claim 1 An apparatus for maintaining a wheeled vehicle longitudinally stationary when the vehicle is disposed substantially unrestrained for free longitudinal movement thereof upon the apparatus, said apparatus comprising: a single moveable surface consisting of a running belt configured to be in groundward contact with all wheels of the vehicle when said vehicle is disposed upon the apparatus; a structure supporting the moveable surface; the moveable surface arranged for movement thereof in the longitudinal direction of the vehicle, said longitudinal direction being aligned from a front to a rear of the vehicle; a controllable motor configured to move the moveable surface; a sensor configured to detect the longitudinal position of the vehicle relative to the supporting structure; a controller configured to respond to a position signal from the sensor, said position signal indicating the longitudinal position of the vehicle; and the controller configured to direct motion of the motor in response to the position signal to maintain the vehicle longitudinally stationary relative to the supporting structure while said vehicle is freely self-propelled upon the apparatus, whereby the apparatus is configured such that a combination of the apparatus and the vehicle disposed substantially unrestrained upon the apparatus would comprise a closed-loop servo control system for maintaining the disposed vehicle longitudinally stationary while said vehicle is operated in a freely self-propelled manner. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising: wherein the controller comprises electronic compensation. ### Claim 3 (depends on 2) The apparatus of claim 2, further comprising: the combination of the apparatus and the vehicle disposed upon the apparatus while being operated, in a freely self-propelled manner; and said combination maintaining the disposed vehicle longitudinally stationary. ### Claim 4 (depends on 3) The apparatus of claim 3, further comprising: a device configured to measure power delivered by the motor to move the moveable surface. ### Claim 5 (depends on 2) The apparatus of claim 2, further comprising: a device configured to measure power delivered by the motor to move the moveable surface. ### Claim 6 (depends on 1) The apparatus of claim 1, further comprising: the combination of the apparatus and the vehicle disposed upon the apparatus while being operated in a freely self-propelled manner; and said combination maintaining the disposed vehicle longitudinally stationary. ### Claim 7 (depends on 6) The apparatus of claim 6, further comprising: a device configured to measure power delivered by the motor to move the moveable surface. ### Claim 8 (depends on 1) The apparatus of claim 1, further comprising: a device configured to measure power delivered by the motor to move the moveable surface. ### Claim 9 An apparatus for maintaining a wheeled vehicle longitudinally stationary when the vehicle is disposed substantially unrestrained for free longitudinal movement thereof upon the apparatus, said apparatus comprising: at least one moveable surface with each said moveable surface configured to be in groundward contact with a respective wheel of the vehicle when said vehicle is disposed upon the apparatus; a structure supporting the at least one moveable surface; the one or more moveable surfaces each disposed for synchronous motion thereof in the longitudinal direction of the vehicle, said longitudinal direction being aligned from a front to a rear of the vehicle; a controllable motor configured to move the at least one moveable surface; a sensor configured to detect the longitudinal position of the vehicle relative to the supporting structure; a controller with electronic compensation configured to respond to a position signal from the sensor, said position signal indicating the longitudinal position of the vehicle; and the controller configured to direct motion of the motor in response to the position signal to maintain the vehicle longitudinally stationary relative to the supporting structure while said vehicle is freely self-propelled upon the apparatus; whereby the apparatus is configured such that a combination of the apparatus and the vehicle disposed substantially unrestrained upon the apparatus would comprise a closed-loop servo control system for maintaining the disposed vehicle longitudinally stationary while said vehicle is operated in a freely self-propelled manner. ### Claim 10 (depends on 9) The apparatus of claim 9, further comprising: the combination of the apparatus and the vehicle disposed upon the apparatus while being operated in a freely self-propelled manner; and said combination maintaining the disposed vehicle longitudinally stationary. ### Claim 11 (depends on 9) The apparatus of claim 9, further comprising: a device configured to measure power delivered by the motor to move the one or more moveable surfaces. ### Claim 12 (depends on 10) The apparatus of claim 10, further comprising: a device configured to measure power delivered by the motor to move the one or more moveable surfaces. ### Claim 13 A method for maintaining a wheeled vehicle longitudinally stationary while the vehicle is disposed substantially unrestrained for free longitudinal movement thereof upon a supporting apparatus, said method comprising: arranging the vehicle substantially unrestrained upon the supporting apparatus for free movement in the longitudinal direction of the vehicle, wherein said longitudinal direction is aligned from a front to a rear of the vehicle, and wherein said supporting apparatus comprises: a single moveable surface consisting of a running belt configured to be in groundward contact with all wheels of the vehicle; a structure supporting the moveable surface; the moveable surface arranged for movement thereof in the longitudinal direction of the vehicle; a controllable motor configured to move the moveable surface; a sensor configured to detect the longitudinal position of the vehicle relative to the supporting structure; a controller configured to respond to a position signal from the sensor, said position signal indicating the longitudinal position of the vehicle; and the controller configured to direct motion of the motor in response to the position signal to maintain the vehicle longitudinally stationary relative to the supporting structure while said vehicle is freely self-propelled upon the apparatus; operating the vehicle in a self-propelled manner; powering the motor to move the moveable surface; and controlling the motor to maintain the disposed vehicle longitudinally stationary relative to the supporting structure. ### Claim 14 (depends on 13) The method of claim 13, further comprising: wherein the supporting apparatus comprises a servo control system; and wherein the controller comprises electronic compensation. ### Claim 15 (depends on 14) The method of claim 14, further comprising: measuring power being transmitted through the wheels of the vehicle. ### Claim 16 (depends on 15) The method of claim 15, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 17 (depends on 14) The method of claim 14, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 18 (depends on 14) The method of claim 14, further comprising: wherein the vehicle is an automotive vehicle comprising at least three wheels. ### Claim 19 (depends on 13) The method of claim 13, further comprising: measuring power being transmitted through the wheels of the vehicle. ### Claim 20 (depends on 19) The method of claim 19, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 21 (depends on 19) The method of claim 19, further comprising: wherein the vehicle is an automotive vehicle comprising at least three wheels. ### Claim 22 (depends on 13) The method of claim 13, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 23 A method for maintaining a wheeled vehicle longitudinally stationary while the vehicle is disposed substantially unrestrained for free longitudinal movement thereof upon a supporting apparatus, said method comprising: arranging the vehicle substantially unrestrained upon the supporting apparatus for free movement in the longitudinal direction of the vehicle, wherein said longitudinal direction is aligned from a front to a rear of the vehicle, and wherein said supporting apparatus comprises: at least one moveable surface with each said moveable surface configured to be in groundward contact with a respective wheel of the vehicle; a structure supporting the one or more moveable surfaces; the one or more moveable surfaces each disposed for synchronous motion thereof in the longitudinal direction of the vehicle; a controllable motor configured to move the one or more moveable surfaces; a sensor configured to detect the longitudinal position of the vehicle relative to the supporting structure; a controller with electronic compensation configured to respond to a position signal from the sensor, said position signal indicating the longitudinal position of the vehicle; and the controller configured to direct motion of the motor in response to the position signal to maintain the vehicle longitudinally stationary relative to the supporting structure while said vehicle is freely self-propelled upon the apparatus; operating the vehicle in a self-propelled manner; powering the motor to move the moveable surface; and controlling the motor to maintain the vehicle longitudinally stationary relative to the supporting structure. ### Claim 24 (depends on 23) The method of claim 23, further comprising: wherein the supporting apparatus further comprises a servo control system. ### Claim 25 (depends on 24) The method of claim 24, further comprising: measuring power being transmitted through the wheels of the vehicle. ### Claim 26 (depends on 25) The method of claim 25, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 27 (depends on 25) The method of claim 25, further comprising: wherein the vehicle is an automotive vehicle comprising at least three wheels. ### Claim 28 (depends on 24) The method of claim 24, further comprising: wherein the vehicle is a non-automotive cycle. ### Claim 29 (depends on 24) The method of claim 24, further comprising: wherein the vehicle is an automotive vehicle comprising at least three wheels. ### Claim 30 (depends on 23) The method of claim 23, further comprising: measuring power being transmitted through the wheels of the vehicle.