A first shaft segment and a second shaft segment are joined by a first fastener and a second fastener to form a shaft test assembly. The first shaft segment and the second shaft segment are each curved between first and second circumferential ends. A method of testing a shaft includes displacing a first applicator part relative a second applicator part to exert a load on the shaft test assembly. The resulting shear stress on the shaft test assembly can be measured to determine material properties of the shaft. A first applicator part extends at least partially into the shaft test assembly and interfaces with the first shaft segment to apply a load. A second applicator part extends at least partially into the shaft test assembly and interfaces with the second shaft segment to apply a load.

In the present invention, an input-side control device generates an input-side torque command signal Tr using an engine torque command signal, an input-side velocity detection signal ω, and an input-side shaft torque detection signal Tsh, and is provided with: a shaft torque controller that generates a torque command signal on the basis of the engine torque command signal and an input shaft torque detection signal; and an inertia compensator that feeds back an inertia compensation signal generated by multiplying a set inertia value Jset by the input-side velocity detection signal. The shaft torque controller is provided with a first low-pass filter that, from the engine torque command signal, allows a high-frequency component to decay; and the inertia compensator is provided with a second low-pass filter that, from the input-side velocity detection signal, allows a high-frequency component to decay.

The invention relates to a method for ascertaining the backlash (40) of a gear (24) which is coupled to an electric machine (12) of a vehicle which has at least one electric machine (12). According to the method, at least the following steps are carried out: a) detecting the rotational speed of the at least one electric machine (12) during a driving intervention (80) and detecting rotational speed fluctuations produced therefrom, b) evaluating a high-frequency vibration (60) which is generated as a result of the gear (24) reaching a lower stop (54) in delay phases (56) and reaching an upper stop (50) when reversing the rotational direction in acceleration phases (58), c) filtering out high-frequency components from the high-frequency vibration (60) according to step b), wherein position information (42), relating to a corresponding rotational angle, from the rotational speed signal is saved in the event said components occur, and d) evaluating the distance between the upper stop (52) and the lower stop (54) and ascertaining the backlash (40) from the difference of the position information (42) between the upper stop (52) and the lower stop (54).

An input-side control device includes: a feedback controller that generates a first control input signal for eliminating the difference between a model speed signal ωm and a speed detection signal ω by using the signal difference between a higher order torque command signal Tref and an axial torque detection signal Tsh to generate the model speed signal ωm which corresponds to the rotational speed of an inertial body having a set moment of inertia Jset moving under a torque corresponding to the signal difference; a feed-forward controller that generates a second control input signal by multiplying the signal difference by k.Math.Jdy/Jset; and a low-pass filter that generates a torque command signal Tr from a signal obtained by combining the outputs of the controllers and attenuating components at a higher frequency than a cut-off frequency fc set in the vicinity of the resonant frequency.

The invention relates to a method for controlling, more particularly in a closed-loop manner, a test bench for a powertrain with a real transmission, the method including calculating a desired value of a control parameter, more particularly a desired rotational speed, at the transmission output of the real transmission by means of a model that represents the transmission and at least one further component, more particularly a shaft, of the output side of the powertrain as virtual components, on the basis of at least one measurement parameter, more particularly a rotational speed and/or a torque, measured on the powertrain; and controlling the test bench, more particularly a load machine, on the basis of the desired value.

The invention relates to a method for controlling, more particularly in a closed-loop manner, a test bench for a powertrain with a real transmission, the method including calculating a desired value of a control parameter, more particularly a desired rotational speed, at the transmission output of the real transmission by means of a model that represents the transmission and at least one further component, more particularly a shaft, of the output side of the powertrain as virtual components, on the basis of at least one measurement parameter, more particularly a rotational speed and/or a torque, measured on the powertrain; and controlling the test bench, more particularly a load machine, on the basis of the desired value.

The mechanical characteristic estimating method is a method for estimating a value of a mechanical characteristic parameter of a test piece W provided with a first shaft S1, and a second shaft S2 and a third shaft S3 which are connected to the first shaft S1. The mechanical characteristic estimating method includes: a first measuring step of measuring a resonant frequency ωL of the test piece in a state in which a gear ratio of the transmission TM1 and the differential gear TM2 is set to a first gear ratio gL; a second measuring step of measuring the resonant frequency ωH of the test piece in a state in which the gear ratio is set to a second gear ratio gH; and an estimating step of calculating the resonant frequencies ωL and ωH, the gear ratios gL and gH, and an estimated value of a spring stiffness.

The mechanical characteristic estimating method is a method for estimating a value of a mechanical characteristic parameter of a test piece W provided with a first shaft S1, and a second shaft S2 and a third shaft S3 which are connected to the first shaft S1. The mechanical characteristic estimating method includes: a first measuring step of measuring a resonant frequency ωL of the test piece in a state in which a gear ratio of the transmission TM1 and the differential gear TM2 is set to a first gear ratio gL; a second measuring step of measuring the resonant frequency ωH of the test piece in a state in which the gear ratio is set to a second gear ratio gH; and an estimating step of calculating the resonant frequencies ωL and ωH, the gear ratios gL and gH, and an estimated value of a spring stiffness.

In the present invention, an input-side control device generates an input-side torque command signal Tr using an engine torque command signal, an input-side velocity detection signal ω, and an input-side shaft torque detection signal Tsh, and is provided with: a shaft torque controller that generates a torque command signal on the basis of the engine torque command signal and an input shaft torque detection signal; and an inertia compensator that feeds back an inertia compensation signal generated by multiplying a set inertia value Jset by the input-side velocity detection signal. The shaft torque controller is provided with a first low-pass filter that, from the engine torque command signal, allows a high-frequency component to decay; and the inertia compensator is provided with a second low-pass filter that, from the input-side velocity detection signal, allows a high-frequency component to decay.

This abnormality detection device is provided with a first encoder for detecting the rotation angle of an input shaft of a decelerator, and a second encoder for detecting the rotation angle of an output shaft of the decelerator. An operation control unit controls a servo motor such that the position acquired from the output of the second encoder corresponds to a position determined by an operation program. A detection unit calculates the angle difference, which is the difference between the rotation angle acquired from output of the first encoder and the rotation angle acquired from output of the second encoder. The detection unit determines whether or not the decelerator is abnormal on the basis of the angle difference.