# US 11,997,951 B2 · Lawn mower and control system determining whether ground is lawn > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,997,951 B2 - Document ID: US11997951B2 - Status: Granted - Kind: B2 - Application number: 16/982,169 - Filed: 2018-03-23 - Published: 2021-01-28 - Granted: 2024-06-04 - Earliest claimed: 2018-03-23 - Assignees: Honda Motor Co., Ltd. - Applicants: Honda Motor Co., Ltd. - Inventors: Runa Kaneko; Koji Kuriyagawa - Web page: https://patentgrep.com/patent/US11997951B2 ## CPC - A01D 75/28: Control mechanisms for harvesters or mowers when moving on slopes; Devices preventing lateral pull - B60L 3/10: Indicating wheel slip {; Correction of wheel slip} - A01D 34/006: {Control or measuring arrangements} - A01D 34/008: {for automated or remotely controlled operation} - A01D 34/64: mounted on a vehicle, e.g. a tractor, or drawn by an animal or a vehicle (A01D34/695 takes precedence) - A01D 34/86: for use on sloping ground, e.g. on embankments {or in ditches}(undercarriages or frames specially adapted for harvesters or mowers A01D67/00; control mechanisms for harvesters or mowers when moving on slopes A01D75/28) - A01D 69/00: Driving mechanisms or parts thereof for harvesters or mowers (driving mechanisms for the cutters of mowers or harvesters A01D34/00) - B60L 3/102: {of individual wheels} - B60L 15/20: for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed - B60W 30/18172: {Preventing, or responsive to skidding of wheels} - A01D 2101/00: Lawn-mowers - B60L 2200/22: Microcars, e.g. golf cars - B60L 2200/40: Working vehicles - B60L 2240/642: Slope of road - B60L 2240/645: Type of road - B60L 2240/647: Surface situation of road, e.g. type of paving - B60W 2510/083: Torque - B60W 2520/26: Wheel slip - B60W 2552/15: Road slope, i.e. the inclination of a road segment in the longitudinal direction - B60W 2552/40: Coefficient of friction - B60Y 2200/223: Ridable lawn mowers - B60Y 2200/91: Electric vehicles - Y02T 10/64: Electric machine technologies in electromobility - Y02T 10/72: Electric energy management in electromobility - Y02T 90/16: Information or communication technologies improving the operation of electric vehicles - A01D: HARVESTING; MOWING - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract The configuration includes: a motor for driving a driving wheel (rear wheel) provided to a body; a slip ratio calculating section for calculating a slip ratio while the lawn mower is traveling; a friction coefficient calculating section for calculating a friction coefficient of a ground on which the lawn mower is traveling; a determination section for determining whether the ground on which the lawn mower is traveling is a lawn based on a relationship between the slip ratio and the friction coefficient and a drive controlling section for controlling the motor based on a determination result from the determination section. This configuration allows suitable driving operability for both of a case where the ground on which a lawn mowers traveling is a lawn and a case where the ground is other than a lawn. ## Claims ### Claim 1 A lawn mower comprising: a motor configured to drive a driving wheel provided to a body; a slip ratio calculating section configured to calculate a slip ratio indicating a magnitude of slip of the driving wheel while the lawn mower is traveling; a friction coefficient calculating section configured to calculate a friction coefficient of a ground on which the lawn mower is traveling; a determination section configured to determine whether the ground on which the lawn mower is traveling is a lawn based on lawn determination data indicating a relationship between the slip ratio calculated by the slip ratio calculating section and the friction coefficient calculated by the friction coefficient calculating section; and a drive controlling section configured to control the motor based on a determination result of the determination section, the determination result being by the lawn determination data as to whether the ground on which the lawn mower is traveling is a lawn. ### Claim 2 (depends on 1) The lawn mower according to claim 1, wherein when the determination section determines that the ground on which the lawn mower is traveling is a lawn, the drive controlling section performs lawn traveling control to rotate the driving wheel at a torque greater than or equal to a predetermined torque, and when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the drive controlling section performs non-lawn traveling control to rotate the driving wheel at a torque less than the predetermined torque. ### Claim 3 (depends on 2) The lawn mower according to claim 2, wherein the lawn mower comprises a work section controlling section configured to control a lawn cutting blade, and when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the work section controlling section puts the lawn cutting blade in a non-operational state. ### Claim 4 (depends on 3) The lawn mower according to claim 3, wherein when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the work section controlling section puts the lawn cutting blade in an elevated state. ### Claim 5 (depends on 2) The lawn mower according to claim 2, wherein: the lawn mower comprises a traction control system configured to implement a traction control system, when the determination section determines that the ground on which the lawn mower is traveling is a lawn, the drive controlling section turns on the traction control system, and when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the drive controlling section turns off the traction control system. ### Claim 6 (depends on 2) The lawn mower according to claim 2, wherein: the slip ratio calculating section calculates a slip ratio for each of left and right sides of the body, the friction coefficient calculating section calculates a friction coefficient for each of the left and right sides of the body, and when the determination section determines that the ground on which the lawn mower is traveling is a lawn for at least one of the left and right sides of the body, the drive controlling section performs the lawn traveling control. ### Claim 7 (depends on 1) The lawn mower according to claim 1, wherein: the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 8 (depends on 1) The lawn mower according to claim 1, wherein: the body is provided with a driven wheel, the slip ratio calculating section calculates the slip ratio based on a driven wheel speed of the driven wheel and a driving wheel speed indication value of the driving wheel, and the friction coefficient calculating section calculates the friction coefficient based on the driven wheel speed, of the driven wheel, used for calculating the slip ratio. ### Claim 9 A control system for a lawn mower comprising a body and a motor configured to drive a driving wheel provided to the body, the control system comprising: a slip ratio calculating section configured to calculate a slip ratio indicating a magnitude of slip of the driving wheel while the lawn mower travels; a friction coefficient calculating section configured to calculate a friction coefficient of a ground on which the lawn mower is traveling; a determination section configured to determine whether the ground on which the lawn mower is traveling is a lawn based on lawn determination data indicating a relationship between the slip ratio calculated by the slip ratio calculating section and the friction coefficient calculated by the friction coefficient calculating section; and a control section configured to control the motor based on a determination result of the determination section, the determination result being by the lawn determination data as to whether the ground on which the lawn mower is traveling is a lawn. ### Claim 10 (depends on 3) The lawn mower according to claim 3, wherein the lawn mower comprises a traction control system configured to implement a traction control system, when the determination section determines that the ground on which the lawn mower is traveling is a lawn, the drive controlling section turns on the traction control system, and when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the drive controlling section turns off the traction control system. ### Claim 11 (depends on 4) The lawn mower according to claim 4, wherein the lawn mower comprises a traction control system configured to implement a traction control system, when the determination section determines that the ground on which the lawn mower is traveling is a lawn, the drive controlling section turns on the traction control system, and when the determination section determines that the ground on which the lawn mower is traveling is other than a lawn, the drive controlling section turns off the traction control system. ### Claim 12 (depends on 3) The lawn mower according to claim 3, wherein the slip ratio calculating section calculates a slip ratio for each of left and right sides of the body, the friction coefficient calculating section calculates a friction coefficient for each of the left and right sides of the body, and when the determination section determines that the ground on which the lawn mower is traveling is a lawn for at least one of the left and right sides of the body, the drive controlling section performs the lawn traveling control. ### Claim 13 (depends on 4) The lawn mower according to claim 4, wherein the slip ratio calculating section calculates a slip ratio for each of left and right sides of the body, the friction coefficient calculating section calculates a friction coefficient for each of the left and right sides of the body, and when the determination section determines that the ground on which the lawn mower is traveling is a lawn for at least one of the left and right sides of the body, the drive controlling section performs the lawn traveling control. ### Claim 14 (depends on 5) The lawn mower according to claim 5, wherein the slip ratio calculating section calculates a slip ratio for each of left and right sides of the body, the friction coefficient calculating section calculates a friction coefficient for each of the left and right sides of the body, and when the determination section determines that the ground on which the lawn mower is traveling is a lawn for at least one of the left and right sides of the body, the drive controlling section performs the lawn traveling control. ### Claim 15 (depends on 2) The lawn mower according to claim 2, wherein the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 16 (depends on 3) The lawn mower according to claim 3, wherein the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 17 (depends on 4) The lawn mower according to claim 4, wherein the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 18 (depends on 5) The lawn mower according to claim 5, wherein the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 19 (depends on 6) The lawn mower according to claim 6, wherein the lawn mower comprises an inclination angle detecting section configured to detect an inclination angle of the body in a left-right direction, and the friction coefficient calculating section comprises a correction section configured to correct the friction coefficient based on the inclination angle detected by the inclination angle detecting section. ### Claim 20 (depends on 2) The lawn mower according to claim 2, wherein the body is provided with a driven wheel, the slip ratio calculating section calculates the slip ratio based on a driven wheel speed of the driven wheel and a driving wheel speed indication value of the driving wheel, and the friction coefficient calculating section calculates the friction coefficient based on the driven wheel speed, of the driven wheel, used for calculating the slip ratio. ### Claim 21 (depends on 1) The lawn mower according to claim 1, wherein the lawn determination data indicates the relationship that the friction coefficient is about 0.3 when the slip ratio is 0.1. ### Claim 22 (depends on 9) The lawn mower according to claim 9, wherein the lawn determination data indicates the relationship that the friction coefficient is about 0.3 when the slip ratio is 0.1.