# US 12,003,199 B2 · Mobility assistance device and driving method therof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,199 B2 - Document ID: US12003199B2 - Status: Granted - Kind: B2 - Application number: 17/223,023 - Filed: 2021-04-06 - Published: 2022-07-07 - Granted: 2024-06-04 - Earliest claimed: 2021-01-04 - Assignees: Wistron Corporation - Applicants: Wistron Corporation - Inventors: Fu-Nen Lo; Ke-Yu Lan - Web page: https://patentgrep.com/patent/US12003199B2 ## CPC - H02P 6/04: Arrangements for controlling or regulating the speed or torque of more than one motor (H02P6/10 takes precedence) - H02P 23/14: Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage - A61H 1/0237: {for the lower limbs} - A61H 3/00: Appliances for aiding patients or disabled persons to walk about (apparatus for helping babies to walk A47D13/04 {; applying electrical currents by contact electrodes for stimulating motor muscles, e.g. walking assistance A61N1/36003}) - B25J 9/0006: {Exoskeletons, i.e. resembling a human figure} - B25J 9/126: {Rotary actuators} - H02P 6/30: Arrangements for controlling the direction of rotation (H02P6/22 takes precedence) - H02P 25/03: with brushless excitation - A61H 2003/007: {secured to the patient, e.g. with belts} - A61H 2201/1215: Rotary drive - A61H 2201/164: Feet or leg, e.g. pedal - A61H 2201/165: Wearable interfaces - A61H 2201/5058: Sensors or detectors - A61H 2201/5069: Angle sensors - A61H 2201/5079: Velocity sensors - A61H 2203/0406: Standing on the feet - A61H 2205/106: for the lower legs - A61H 2205/108: for the upper legs - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS - A61H: PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY (electrotherapy, magnetotherapy, radiation therapy or ultrasound therapy A61N) - 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}) ## Abstract A mobility assistance device and a driving method thereof are provided. The mobility assistance device includes at least one bracket and a driving device which drives the at least one bracket. The driving device includes a brushless direct current (DC) motor, a rotor angle sensor, and a sensing driver. The rotor angle sensor senses the angle of the brushless DC motor. The sensing driver uses a corresponding algorithm to estimate a corresponding angle corresponding to an angle velocity switching of the brushless DC motor. The corresponding angle is used as an angle of the brushless DC motor. The sensing driver drives the brushless DC motor according to the corresponding angle, so that the brushless DC motor provides supporting force to the at least one bracket. ## Claims ### Claim 1 A mobility assistance device, comprising: at least one bracket; and a driving device, coupled to the at least one bracket, wherein the driving device comprises: a brushless direct current (DC) motor; a rotor angle sensor, sensing an angle of the brushless DC motor; and a sensing driver, coupled to the rotor angle sensor, and using a corresponding algorithm to estimate a corresponding angle corresponding to an angle velocity switching of the brushless DC motor, wherein the corresponding angle is used as an angle of the brushless DC motor, the sensing driver drives the brushless DC motor according to the corresponding angle, so that the brushless DC motor provides a supporting force to the at least one bracket, wherein the rotor angle sensor detects the angle of the brushless DC motor and generates a detection result, the sensing driver determines whether a current speed of the brushless DC motor exceeds a predetermined speed according to the detection result, thereby determining whether an angle velocity switching of the brushless DC motor occurs, wherein the corresponding algorithm comprises a Hall sensor angle compensation algorithm and a sensorless angle compensation algorithm, the Hall sensor angle compensation algorithm estimates a first angle based on the detection result of the brushless DC motor, and the sensorless angle compensation algorithm estimates a second angle based on a plurality of parameters and a power supply condition of the brushless DC motor, wherein the sensing driver further calculates a current angle error between the first angle and the second angle, the sensing driver determines whether the angle velocity switching of the brushless DC motor occurs, so as to determine whether to use the first angle obtained from the Hall sensor angle compensation algorithm or the second angle obtained from the sensorless angle compensation algorithm as the angle of the brushless DC motor, and drive the brushless DC motor according to the angle of the brushless DC motor, wherein when the current angle error is larger than a predetermined sensitivity or the current speed of the brushless DC motor does not exceed the predetermined speed, the sensing driver adopts the first angle obtained from the Hall sensor angle compensation algorithm as the angle of the brushless DC motor, when the current angle error is not larger than the predetermined sensitivity and the current speed of the brushless DC motor exceeds the predetermined speed, the sensing driver adopts the second angle obtained from the sensorless angle compensation algorithm as the angle of the brushless DC motor. ### Claim 2 (depends on 1) The mobility assistance device according to claim 1, wherein the condition of determining whether the angle velocity switching of the brushless DC motor occurs is: the sensing driver determines the condition where the angle of the brushless DC motor changes from a first speed range to a second speed range, or, the sensing driver determines the condition where the angle of the brushless DC motor changes from the second speed range to the first speed range, wherein the first speed range indicates a state where the angle of the brushless DC motor is larger than the predetermined speed in the detection result, and the second speed range indicates a state where the angle of the brushless DC motor is smaller than or equal to the predetermined speed in the detection result. ### Claim 3 (depends on 1) The mobility assistance device according to claim 1, wherein the rotor angle sensor is a Hall sensor. ### Claim 4 (depends on 1) The mobility assistance device according to claim 1, wherein the sensorless angle compensation algorithm calculates a back electromotive force of the brushless DC motor based on an input current of the brushless DC motor and the plurality of parameters of the brushless DC motor, thereby estimating the second angle, wherein the sensorless angle compensation algorithm does not estimate the second angle based on the detection result of the brushless DC motor. ### Claim 5 (depends on 1) The mobility assistance device according to claim 1, wherein the at least one bracket comprises: a first bracket, coupled to the driving device; and a second bracket, coupled to the driving device, wherein the sensing driver is configured to drive the brushless DC motor according to the corresponding angle, such that the brushless DC motor supplies a supporting force to the first bracket and the second bracket respectively. ### Claim 6 (depends on 5) The mobility assistance device according to claim 5, further comprising: a first side shield, fixed on the first bracket; at least one first strap, connected to the first bracket or the first side shield; a second side shield, fixed on the second bracket; and at least one second strap, connected to the first bracket or the second side shield, wherein the first side shield, the at least one first strap, the second side shield and the at least one second strap are configured for fixing the mobility assistance device to a user. ### Claim 7 A driving method of a mobility assistance device, wherein the mobility assistance device comprises at least one bracket and a driving device coupled to the at least one bracket, the driving device comprises a brushless DC motor, wherein the driving method comprises: sensing an angle of the brushless DC motor to determine whether an angle velocity switching of the brushless DC motor occurs; corresponding to whether the angle velocity switching of the brushless DC motor occurs, using a corresponding algorithm to estimate a corresponding angle, wherein the corresponding angle is used as the angle of the brushless DC motor; and driving the brushless DC motor according to the corresponding angle, so that the brushless DC motor provides a supporting force to the at least one bracket, wherein the corresponding algorithm comprises a Hall sensor angle compensation algorithm and a sensorless angle compensation algorithm, the Hall sensor angle compensation algorithm estimates a first angle based on the detection result of the brushless DC motor, and the sensorless angle compensation algorithm estimates a second angle based on a plurality of parameters and a power supply condition of the brushless DC motor, the driving method further comprising: calculating a current angle error between the first angle and the second angle, wherein the step of using the corresponding algorithm to estimate the corresponding angle which is used as the angle of the brushless DC motor corresponding to whether the angle velocity switching of the brushless DC motor occurs comprises: determining whether the angle velocity switching of the brushless DC motor occurs, so as to determine whether to use the first angle obtained from the Hall sensor angle compensation algorithm or a second angle obtained from the sensorless angle compensation algorithm as the angle of the brushless DC motor, when the current angle error is larger than the predetermined sensitivity or the current speed of the brushless DC motor does not exceed the predetermined speed, the first angle obtained from the Hall sensor angle compensation algorithm is adopted as the angle of the brushless DC motor; and when the current angle error is not larger than the predetermined sensitivity and the current speed of the brushless DC motor exceeds the predetermined speed, the second angle obtained from the sensorless angle compensation algorithm is adopted as the angle of the brushless DC motor. ### Claim 8 (depends on 7) The driving method according to claim 7, wherein the step of determining whether the angle velocity switching of the brushless DC motor occurs comprises: detecting the angle of the brushless DC motor and generating a detection result; and determining, according to the detection result, whether a current speed of the brushless DC motor exceeds a predetermined speed, so as to determine whether the angle velocity switching of the brushless DC motor occurs, wherein the condition of determining whether the angle velocity switching of the brushless DC motor occurs is: determining the condition where the angle of the brushless DC motor changes from a first speed range to a second speed range, or, determining the condition where the angle of the brushless DC motor changes from the second speed range to the first speed range, wherein the first speed range indicates a state where the angle of the brushless DC motor is larger than the predetermined speed in the detection result, and the second speed range indicates a state where the angle of the brushless DC motor is smaller than or equal to the predetermined speed in the detection result. ### Claim 9 (depends on 7) The driving method according to claim 7, wherein the sensorless angle compensation algorithm calculates a back electromotive force of the brushless DC motor based on an input current of the brushless DC motor and a plurality of parameters of the brushless DC motor, thereby estimating the second angle, wherein the sensorless angle compensation algorithm does not estimate the second angle based on the detection result of the brushless DC motor.