# US 7,610,800 B2 · Method and system for collecting crankshaft position data > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,610,800 B2 - Document ID: US7610800B2 - Status: Granted - Kind: B2 - Application number: 11/847,109 - Filed: 2007-08-29 - Published: 2009-03-05 - Granted: 2009-11-03 - Earliest claimed: 2007-08-29 - Assignees: GM Global Technology Operations LLC - Inventors: Xuan Dung T. Avallone; John L. Lahti; David S. Mathews; Robert C. Simon, Jr.; Leonard G. Wozniak; William R. Cawthorne; Robert S Wickman - Web page: https://patentgrep.com/patent/US7610800B2 ## CPC - B60W 20/15: Control strategies specially adapted for achieving a particular effect - B60K 6/48: Parallel type - B60W 10/08: including control of electric propulsion units, e.g. motors or generators - B60W 50/04: Monitoring the functioning of the control system - F02D 41/009: {using means for generating position or synchronisation signals} - F02D 41/0097: {using means for generating speed signals} - B60W 20/00: Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} - B60W 2050/0005: {Processor details or data handling, e.g. memory registers or chip architecture} - F02D 41/123: {the fuel injection being cut-off} - F02D 41/2441: {characterised by the learning conditions} - F02D 41/2451: {characterised by what is learned or calibrated} - Y02T 10/62: Hybrid 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 - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method for collecting crankshaft position data includes rotating a crankshaft of an engine within a selected angular velocity range without any fuel being applied to the engine and measuring crankshaft position data. ## Claims ### Claim 1 A method for collecting position data of an internal combustion engine crankshaft comprising: monitoring crankshaft velocity; rotating the crankshaft into a selected angular velocity range; maintaining the crankshaft within the selected angular velocity range without any fuel being applied to said engine; measuring crankshaft position data while the crankshaft is maintained within the selected angular velocity range; and determining a crankshaft error factor based on the measured crankshaft position data. ### Claim 2 (depends on 1) The method of claim 1, wherein rotating the crankshaft comprises rotating the crankshaft by backdriving the engine. ### Claim 3 (depends on 2) The method of claim 2, wherein backdriving the engine comprises backdriving the engine during vehicle coasting. ### Claim 4 (depends on 2) The method of claim 2, wherein the crankshaft is operatively coupled to a hybrid transmission including an electric motor, and backdriving the engine comprises backdriving the engine during vehicle coasting through the hybrid transmission and maintaining the crankshaft within the selected angular velocity range comprises controlling crankshaft speed with the electric motor. ### Claim 5 (depends on 2) The method of claim 2, wherein backdriving the engine comprises backdriving the engine with a dynamometer. ### Claim 6 (depends on 1) The method of claim 1, wherein rotating the crankshaft into the selected angular velocity range comprises rotating the crankshaft into the selected angular velocity range by fueling the engine. ### Claim 7 (depends on 1) The method of claim 1, wherein maintaining the crankshaft within the selected angular velocity range comprises rotating the crankshaft with an electric motor. ### Claim 8 (depends on 7) The method of claim 7, wherein rotating the crankshaft into the selected angular velocity range comprises rotating the crankshaft into the selected angular velocity range with the electric motor. ### Claim 9 (depends on 7) The method of claim 7, wherein said electric motor and said engine are part of a hybrid drive system. ### Claim 10 (depends on 1) The method of claim 1, said measuring staffing after a transitory period. ### Claim 11 (depends on 1) The method of claim 1, said method further comprising processing said crankshaft position data. ### Claim 12 (depends on 11) The method of claim 11, said processing including discarding data points of said crankshaft position data measured during a transitory period. ### Claim 13 (depends on 11) The method of claim 11, said processing including discarding data points of said crankshaft position data measured subsequent to any data point of said crankshaft position data falling outside of said selected angular velocity range. ### Claim 14 (depends on 11) The method of claim 11, said processing including calculation of the crankshaft error factor. ### Claim 15 (depends on 11) The method of claim 11, said processing including calculation of crankshaft error factors for each of a plurality of crankshaft positions. ### Claim 16 A crankshaft position data measurement system for an internal combustion engine comprising: means operative to rotate said crankshaft into a selected angular velocity range; means for maintaining the crankshaft within the selected angular velocity range with no fuel being applied to said engine; a measurement device operative to measure crankshaft position data while the crankshaft is maintained within the selected angular velocity range with no fuel being applied to said engine; and a processor determining crank error values based on the measured crankshaft position data. ### Claim 17 (depends on 16) The system of claim 16, said means operative to rotate said crankshaft into the selected angular velocity range comprising an electric motor. ### Claim 18 (depends on 16) The system of claim 16, said means operative to rotate said crankshaft into the selected angular velocity range comprising said engine operative to accelerate said crankshaft to a fuel cutoff point, and said means for maintaining the crankshaft within the selected angular velocity range comprising an electric motor operative to rotate said crankshaft subsequent to said fuel cutoff point. ### Claim 19 (depends on 18) The system of claim 18, said measurement device operative to measure said crankshaft position data during a transitory period after said fuel cutoff point. ### Claim 20 (depends on 16) The system of claim 16, said means operative to rotate said crankshaft into the selected angular velocity range comprising means for backdriving the engine.