# US 2018/0178342 A1 · Work tool positioning system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0178342 A1 - Document ID: US20180178342A1 - Status: Published application - Kind: A1 - Application number: 15/842,102 - Filed: 2017-12-14 - Published: 2018-06-28 - Earliest claimed: 2016-12-23 - Assignees: Caterpillar Inc. - Applicants: Caterpillar Inc. - Inventors: Carey Dean Russell - Web page: https://patentgrep.com/patent/US20180178342A1 ## CPC - B23Q 17/2241: {Detection of contact between tool and workpiece} - B23Q 17/2208: {Detection or prevention of collisions} - B25H 1/0092: {by optical means} - E02F 9/2033: {Limiting the movement of frames or implements, e.g. to avoid collision between implements and the cabin (sub-groups of E02F3/431 of E02F3/435 take precedence; for turntables E02F9/123)} - E02F 9/2058: {Electric or electro-mechanical or mechanical control devices of vehicle sub-units (for vehicles in general B60W)} - E02F 9/264: {Sensors and their calibration for indicating the position of the work tool} - G01C 9/04: Transmission means between sensing element and final indicator for giving an enlarged reading - G05B 19/402: characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position (G05B19/19 takes precedence) - B23B 2270/32: Use of electronics - G05B 2219/37423: Distance, gap between tool and surface sensor - B23Q: DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING (tools of the kind used in lathes or boring machines B23B27/00); MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT - B25H: WORKSHOP EQUIPMENT, e.g. FOR MARKING-OUT WORK; STORAGE MEANS FOR WORKSHOPS (storing or packaging B65) - E02F: DREDGING; SOIL-SHIFTING (winning peat E21C49/00) - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - 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) - B23B: TURNING; BORING (arrangements for copying or controlling B23Q) ## Abstract The disclosure provides a work tool positioning system for a work machine comprising a movable work tool. The work tool positioning system comprises a work tool mounted at an end of a movable arm. At least one proximity sensor is provided for providing a proximity signal indicative of a distance between the at least one proximity sensor and an object in front of the proximity sensor. A processor is configured to receive the proximity signal and to calculate a clearance distance between a reference location on the work tool and an object in front of the proximity sensor. An alert system is provided for alerting an operator of the work machine. The processor is configured to activate one or more alerts when the clearance distance is greater than or equal to a first threshold unloading distance. ## Claims ### Claim 1 A work tool positioning system for a work machine comprising a movable work tool, the work tool positioning system comprising: a work tool mounted at an end of a movable arm; at least one proximity sensor for providing a proximity signal indicative of a distance between the at least one proximity sensor and an object in front of the proximity sensor; a processor configured to receive the proximity signal and to calculate a clearance distance between a reference location on the work tool and an object in front of the proximity sensor; and an alert system for alerting an operator of the work machine; wherein the processor is configured to activate one or more alerts when the clearance distance is greater than or equal to a first threshold unloading distance. ### Claim 2 (depends on 1) A work tool positioning system according to claim 1, wherein the processor is further configured to activate one or more alerts when the clearance distance is greater than or equal to a second threshold unloading distance, wherein the second threshold unloading distance is smaller than the first threshold unloading distance. ### Claim 3 (depends on 2) A work tool positioning system according to claim 2, wherein the one or more alerts vary in direct proportion to distance, between the second threshold unloading distance and the first threshold unloading distance. ### Claim 4 (depends on 1) A work tool positioning system according to claim 1, wherein the processor is further configured to activate one or more alerts when the proximity signal corresponds to a distance which is less than or equal to a first threshold contact distance. ### Claim 5 (depends on 4) A work tool positioning system according to claim 4, wherein the processor is further configured to activate one or more alerts when the proximity signal corresponds to a distance which is less than or equal to a second threshold contact distance, wherein the second threshold contact distance is smaller than the first threshold contact distance. ### Claim 6 (depends on 5) A work tool positioning system according to claim 5, wherein the one or more alerts vary in direct proportion to distance, between the first threshold contact distance and the second threshold contact distance. ### Claim 7 (depends on 4) A work tool positioning system according to claim 4, wherein the processor is further configured to activate a braking system of the work machine when the proximity signal corresponds to a distance which is less than or equal to the first threshold contact distance and/or the second threshold contact distance. ### Claim 8 (depends on 1) A work tool positioning system according to claim 1, wherein the at least one proximity sensor is activated when the movable arm is raised to an angle such that the work tool itself will not be detected by the at least one proximity sensor. ### Claim 9 (depends on 1) A work tool positioning system according to claim 1, wherein the at least one proximity sensor is located at a front end of the work machine. ### Claim 10 (depends on 1) A work tool positioning system according to claim 1, comprising two or more proximity sensors. ### Claim 11 (depends on 1) A work tool positioning system according to claim 1, wherein the alert system comprises means to provide an audible alert. ### Claim 12 (depends on 1) A work tool positioning system according to claim 1, wherein the alert system comprises means to provide at least one visible alert. ### Claim 13 (depends on 1) A work tool positioning system according to claim 1, wherein the alert system comprises a display panel. ### Claim 14 (depends on 1) A work tool positioning system according to claim 1, wherein the work tool comprises a loader bucket. ### Claim 15 (depends on 1) A work tool positioning system according to claim 1, wherein the work tool comprises a loader fork.