# US 2018/0024017 A1 · Method For Determining A Torsional Moment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0024017 A1 - Document ID: US20180024017A1 - Status: Published application - Kind: A1 - Application number: 15/547,570 - Filed: 2015-12-10 - Published: 2018-01-25 - Earliest claimed: 2015-01-30 - Assignees: Siemens Aktiengesellschaft - Applicants: Siemens Aktiengesellschaft - Inventors: WERNER BREUER; MINYI YU - Web page: https://patentgrep.com/patent/US20180024017A1 ## CPC - G01L 3/04: wherein the torque-transmitting element comprises a torsionally-flexible shaft - G01M 7/022: {Vibration control arrangements, e.g. for generating random vibrations} - G01M 17/10: Suspensions, axles or wheels - B60B 17/0006: {Construction of wheel bodies, e.g. disc wheels (B60B17/0003 takes precedence)} - B60B 2320/00: Manufacturing or maintenance operations - B60Y 2200/30: Railway vehicles - B61L 23/047: {Track or rail movements} - B61L 25/028: {Determination of vehicle position and orientation within a train consist, e.g. serialisation} - B61L 27/16: Trackside optimisation of vehicle or train operation - G06N 7/06: Simulation on general purpose computers - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - B60B: VEHICLE WHEELS (making wheels or wheel parts by rolling B21H1/00, by forging, hammering or pressing B21K1/28); CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY - B61L: GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC (brakes or auxiliary equipment B61H, B61K; point or crossing construction E01B) - G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS ## Abstract A method for determining a torsional moment of a wheel set shaft of a rail vehicle during the operation of the rail vehicle is used for a wheel set shaft having two wheels secured to ends of the shaft for rolling on two rails. A model is used to calculate a torsional moment which acts on the wheel set shaft, and the model is based on a torsional vibration of the wheel set shaft at a specified slip action point. The torsional moment acting on the wheel set shaft is ascertained based on the energy of the torsional vibration of the wheel set shaft at the slip action point and based on a damping energy which acts on the torsional vibration of the wheel set shaft. ## Claims ### Claim at position 1 1-11. (canceled) ### Claim 12 A method for determining a torsional moment of a wheel set shaft of a rail vehicle during operation of the rail vehicle, the method comprising the following steps: providing a wheel set shaft having two ends and two wheels each being secured to a respective one of the ends of the shaft for rolling on a respective one of two rails; using a model to calculate a torsional moment acting on the wheel set shaft; basing the model on a torsional vibration of the wheel set shaft at a specified slip action point; and ascertaining the torsional moment acting on the wheel set shaft based on an energy of the torsional vibration of the wheel set shaft at a slip action point and based on a damping energy acting on the wheel set shaft during the torsional vibration. ### Claim 13 (depends on 12) The method according to claim 12, which further comprises: using a model for the energy of the torsional vibration of the wheel set shaft at the slip action point and using a model for the damping energy, both models depending on an amplitude of a vibration angle of the torsional vibration; starting from a starting value for both models, increasing the amplitude of the vibration angle until both models exhibit an equal value for energy at an intersection point; and calculating a torsional moment acting on the wheel set shaft based on the amplitude of the torsional vibration at the intersection point and as a function of a specified torsional rigidity of the shaft. ### Claim 14 (depends on 12) The method according to claim 12, which further comprises determining the torsional moment for at least one of a positive or negative acceleration of the rail vehicle, and using the specified slip action point for at least one of the positive or negative acceleration as an operating state. ### Claim 15 (depends on 12) The method according to claim 12, which further comprises subdividing the model for the energy of the torsional vibration into at least three ranges having different characteristics of a friction coefficient between the wheel and the rail. ### Claim 16 (depends on 15) The method according to claim 15, wherein the friction coefficients depend on a slip of the wheels. ### Claim 17 (depends on 15) The method according to claim 15, which further comprises calculating the energy of the torsional vibration during a torsional vibration at the slip action point for each of the at least three ranges, and adding three energy components together to give an energy of the torsional vibration. ### Claim 18 (depends on 12) The method according to claim 12, which further comprises calculating the energy of the torsional vibration as a function of a specified travelling speed range of the rail vehicle. ### Claim 19 (depends on 18) The method according to claim 18, which further comprises using a maximum energy of the torsional vibration for ascertaining a maximum torsional moment of rotation of the wheel set shaft for an intersection point. ### Claim 20 (depends on 12) The method according to claim 12, which further comprises calculating the energy of the torsional vibration as a function of a specified angular velocity range. ### Claim 21 (depends on 20) The method according to claim 20, which further comprises using a maximum energy for ascertaining a maximum torsional moment of rotation of the wheel set shaft. ### Claim 22 (depends on 12) The method according to claim 12, which further comprises using a sine wave to ascertain a vibration angle of a torsion of the wheel set shaft. ### Claim 23 (depends on 12) The method according to claim 12, which further comprises taking a slip during a torsional vibration into consideration as a function of an angular velocity of the torsional vibration. ### Claim 24 (depends on 12) The method according to claim 12, which further comprises using a respective mechanical connecting structure to connect each wheel to the shaft, and dimensioning at least one of the shaft or the connecting structure so that the wheel set shaft bears the calculated torsional moment without damage. ### Claim 25 (depends on 12) The method according to claim 12, which further comprises using a respective mechanical connecting structure to connect each wheel to the shaft, capturing at least one of a thickness of the shaft or a strength parameter of the connecting structure to check the wheel set shaft, and performing a check with reference to at least one of the thickness of the shaft or the strength parameter to determine whether the wheel set shaft is suitable for bearing the calculated torsional moment without damage.