EP1614448B2 - Training apparatus - Google Patents

Abstract

Training device comprises a rotary angle sensor (6) assigned to a motor (2). The measuring signal from the sensor is fed to a frequency converter (4) and to a control unit (5). A theoretical value for the torque released from the motor is prescribed for the frequent converter by the control unit. Preferred Features: The control unit controls the position of the exercised part to a theoretical value. The frequency converter controls the torque of the motor to a theoretical value prescribed by the control unit.

Description

The invention relates to a training device according to the preamble of claim 1. Such a training device is from the EP 0 853 961 B1 known. In this training device, a frequency converter of a computing device set values for the current intensity and for the frequency of the current of a three-phase motor provided for torque generation. The computing device is supplied with the output of a position sensor, which detects the position of acting as a training organ crank, which is driven by the engine detected. From the position value, the computing device uses stored tables in which all relevant machine-specific characteristic data are stored to determine the values of the current strength and the frequency of the motor current required for a desired course of the torque over the position.

Although this known training device works satisfactorily, it can still be improved with regard to certain functional requirements. Thus, in particular for the application of such training devices to medical rehabilitation measures, both a high accuracy in the maintenance of a desired torque, as well as precisely adjustable limit stops for the range of motion of the training body are required. The latter is important, for example, when the maximum deflection angle of a body joint is to be brought back to the normal value after a surgical intervention by means of gymnastic exercises in defined steps.

From the FR 2 709 067 A1 is a training device with a three-phase motor for torque generation is known in which both the speed of the motor with a frequency-analog rotation rate sensor, as well as the output torque is measured with a force sensor. The measured speed is used to control the frequency and the measured torque to control the magnitude of the motor current. The concept of this training device thus includes two sensors and two coupled control loops and is relatively expensive to implement. Furthermore, the force measurement via a sensor has potential problems in the form of temperature influence, long-term drift and disturbances due to vibration or shock.

In view of this prior art, the present invention seeks to provide a training device of the type mentioned, which complies with a predetermined torque with high accuracy, at the same time limits the range of motion by precisely adjustable stops, and is characterized by simple and reliable structure.

This object is achieved by a training device with the features of claim 1. Advantageous embodiments are specified in the subclaims.

The exercise device according to the invention is characterized in that the rotational control of the motor is detected by means of a rotation angle sensor for measuring torque, the measuring signal is supplied to both the frequency converter, as well as the control device. By means of the control device, the frequency converter is given a setpoint value for the torque to be delivered by the motor into which the measurement signal of the rotation angle sensor is received. The frequency converter adjusts the frequency and the strength of the motor current according to the principle of field-oriented regulation. Although the latter is known per se as a concept for controlling an asynchronous motor, but not in connection with exercise equipment of the kind of interest here.

A significant advantage of the invention over the prior art mentioned in the introduction is that it allows more accurate control of the torque output by the engine. In particular, this is helped by the fact that in the normal operating range of an asynchronous machine, i. is operated at a relatively low slip, where only slight specimen scattering of the torque characteristic is expected. In contrast, the operating range according to said prior art, i. at relatively large slippage, affected by significantly larger specimen spreads. Another advantageous effect of the other operating range is the reduction of the power loss of the engine and thus an energy saving. The lower power loss also makes cooling by forced convection unnecessary, so that the outgoing noise from a fan is avoided. Finally, the direct detection of the angle of rotation of the motor instead of its mathematical determination of a measured angle of rotation of the training body and the dynamics of the control loop sustainably improved.

In an advantageous mode of operation, the controller controls the position of the exerciser to a set point so that the user must apply force to deflect the exerciser from a rest position, and the frequency converter, in turn, controls the motor torque to the setpoint set by the controller, thereby reducing the speed of the motor Size of force to be applied by the user to move the exerciser is determined.

In order to predetermine a predetermined course of the torque as a function of the angle of rotation, the control device comprises two control circuits in cascade structure, namely an outer for regulating the position and an inner for controlling the speed of the exercise organ. For this purpose, an evaluation device is needed, which determines both the position and the rotational speed of the training organ from the measurement signal of the rotational angle sensor and provides as actual variables for the two control circuits.

For safety reasons, it is highly advisable to provide a limiter in the position control loop, which limits the target speed of the training body to a maximum value, so that the engine does not allow the training body to snap back into its predetermined desired position with the system-related maximum speed when the exercising person lets go or slip off him.

In the interest of ergonomics, it is also recommended if in the position control loop, a further limiter is provided which limits the rate of change of the target speed of the exercise organ to a maximum value in order to avoid a jerky movement behavior thereof.

In order to predetermine a specific torque curve as a function of the position of the exerciser and / or its rotational speed according to a specific function, a corresponding transmission element is to be provided in the speed control loop, which realizes these functions. Components of these functions can be sudden changes in torque at certain positions, which can simulate mechanical stops. If such position-dependent torque changes are not designed as sudden, but as running continuously, mechanical stops with springing can be simulated by linearly increasing the torque to be overcome by the user after overcoming a fixed end position, for example with increasing further deflection. Furthermore, a stop damping can be simulated, namely by a continuous increase in the after overcoming a predetermined end position to be overcome torque with increasing speed.

For safety reasons, it makes sense here to limit the setpoint torque of the exercise organ in terms of amount to a maximum value. As a result, it is possible to counteract a possible overstraining of the exercising person and the risk of injury due to improper use of the training device, in particular due to an incorrect posture or the use of impermissible aids.

Since the force exerted by the exerciser on the exercising person depends not only on engine torque and gear reduction but also on a variety of mechanical and / or thermal operating parameters such as gear friction, the temperature of the engine and transmission, and the weight of the exerciser Precisely complying with a force effective on the exerciser for the exercising person requires correcting the desired torque of the motor in response to said mechanical and / or thermal operating parameters of the device. For this purpose, a computing device is required in the speed control loop, which also performs said correction in addition to the conversion of the target torque of the training body in a desired torque of the motor, including their determined by the evaluation device from the measured signal of the rotation angle sensor movement quantities of the training body, such as the actual position and / or the actual speed must be supplied as further input variables. For example, the contribution of the self-weight of the exercise organ to the force depends on the position of the exercise organ. In some cases, said operating parameters are also fixed variables, such as the lever length of the exercise organ.

From the output signal of the rotational angle sensor can be obtained by the evaluation device after conversion into the rotational speed of the training body by repeated time differentiation and the angular acceleration of the training body. This is of interest if inertia effects are also to be included in the aforementioned correction. Thus, the computing device can determine the inertial component of the force exerted by the exerciser on the exercising person from the angular acceleration of the training body as a further mechanical operating parameter and take into account.

Finally, the temperature is one of the essential operating parameters of a training device according to the invention, since both the electrical parameters of the engine, as well as the friction and inertia of the transmission depend on the temperature. To compensate for temperature effects, the target torque of the engine can be temperature-dependent corrected, including the engine and / or the transmission must be assigned at least one temperature sensor for detecting the current temperature. The temperature-dependent correction can be done either together with the mechanical correction in the computing device or in a separate compensation device, which may already be integrated into the frequency converter.

Fig. 1

eine schematische Darstellung eines erfindungsgemäßen Trainingsgerätes,

Fig. 2

die Momentenkennlinie eines Drehstrommotors,

Fig. 3

einen Drehmomentverlauf eines erfindungsgemäßen Trainingsgerätes als Funktion der Position, und

Fig. 4

ein elektrisches Blockschaltbild eines erfindungsgemäßen Trainingsgerätes.

Hereinafter, an embodiment of the invention will be described with reference to the drawings. In these shows

Fig. 1

a schematic representation of a training device according to the invention,

Fig. 2

the torque characteristic of a three-phase motor,

Fig. 3

a torque curve of a training device according to the invention as a function of position, and

Fig. 4

an electrical block diagram of a training device according to the invention.

According to Fig. 1 Among the main components of a training device according to the invention include an exercise member 1, for example in the form of a crank, and a three-phase motor 2, which are interconnected by a reduction gear 3. The motor 2 is driven by a frequency converter 4, which supplies the frequency and the power of the motor 2 Current sets to set a desired torque M _{M of} the motor 2. The frequency converter 4, the target torque M _{M of} the motor 2 is set by a control device 5. For the purpose of the control, the actual size of the motor 2 by means of a rotation angle sensor 6 whose rotation angle φ _M detected and both the frequency converter 4, and the control device 5 is supplied.

The specification of the setpoint value M _{s of} the torque with which the crank 1 is to be driven is effected by an operating unit 7, which has a keypad 8 and a display unit 9. Optionally, a magnetic or chip card reader 10 for data input and / or a bus interface 11 for networking with a central computer, not shown, which controls a plurality of training devices may be provided on the operating unit 7.

To the motor 2 and / or to the transmission 3, a temperature sensor 12 is still attached, the temperature signal T is the frequency converter 4 and / or the control device 5 is supplied to take into account the influence of the temperature in the control and thus to compensate.

In contrast to the prior art, the actual value detection for forming a control loop according to the invention is based on the rotational angle φ _{M of} the motor 2 and not on that of the crank 1. Another in the schematic representation of Fig. 1 not recognizable, but crucial difference is the realization of a field-oriented control of the asynchronous motor 2 by the frequency converter. 4

Field-based control is an algorithm for controlling an asynchronous motor that operates in a frequency converter and is based on a coordinate system rotating with the rotor of the motor. By means of the so-called space pointer transformation, a complex current space vector is obtained in this rotating coordinate system, which can be decomposed into a component parallel to the magnetic flux and a component perpendicular to the magnetic flux. In the steady state, the current components to be regulated are equal quantities, which are held by digital controllers on the respective setpoints. There is a back transformation into a three-phase system, with which the pulse width modulators of the frequency converter can be controlled. The perpendicular to the magnetic flux component of the motor current is proportional to the torque, which is given to the inverter as the setpoint. Depending on the direction of movement, the motor can operate both motorically and regeneratively, whereby the energy not consumed by losses is converted into heat via braking resistors.

The principle of field-oriented control of asynchronous motors is known in the art per se, for example from D. Schröder, "Electric Drives 2", Springer Verlag, 1995, Chap. 15.5 or from J. Vogel, "Electric Drive Technology", 5th Edition, Hüthig-Verlag, 1991, Chap. 5.2.3.3 .. Therefore, it need not be explained in detail here and as such is not the subject of the present invention. However, it has not yet been used in the use of asynchronous motors in exercise equipment, although it offers decisive advantages, especially in this application.

This is based on Fig. 2 clearly, which shows the basic course of the torque characteristic of an asynchronous motor, ie the course of the torque as a function of the speed n, or the slip s. This characteristic curve is known per se and reproduced in a number of works dealing with the control of electric motors, such as in the two previously mentioned textbooks, in a similar form.

Accordingly, the operating behavior of an asynchronous motor is subdivided into a brake area, an engine area and a generator area, the standstill marking the boundary between the brake area and the engine area and the idling case marking the boundary between the engine area and the generator area. The actual torque characteristic is the smooth curve. Also plotted are the straight line passing through the two nominal points and two approximate cams valid only at a greater distance from the two tilting points.

In Fig. 2 The two areas are characterized in which an asynchronous motor is operated as the drive element of a training device on the one hand in field-oriented control in the context of the present invention and on the other hand according to the above-mentioned prior art with a control of the voltage and the frequency of an inverter. While the operating range according to the invention lies between the two tipping points of the motor and generator areas around the idling point, the operating range according to the prior art extends around the standstill, namely from the tipping point of the motor area far into the braking area.

It becomes clear that the operating range according to the invention corresponds to the normal operation of an asynchronous motor, whereas the area provided according to the prior art mentioned at the beginning represents as it were a continuous operation in the starting region and thus an alienation of an asynchronous motor, that is to say abnormal. This results in the prior art, the problem that the characteristic curve is poorly reproducible in its relevant area, as engine manufacturers guarantee compliance with the characteristics only for the normal operating range in the vicinity of the nominal point. In order to make an accurate torque adjustment in said abnormal operating range, the characteristic curve must therefore be measured on each individual copy, which is associated with a high cost, or it must be higher due to the Exemplarstreuungen the curve Tolerances of the accuracy of the set torque can be accepted. This problem is eliminated in the normal operating range, which is observed in the field-oriented control, since the characteristics are exactly right there.

The power loss of an asynchronous motor is also known to be in the normal operating range, i. at low slip, much lower than at large slip. Due to the transition to the normal operating range due to the application of the field-oriented control thus results in a lower heat generation, so that the use of a fan is unnecessary.

A typical torque curve of a training device according to the invention as a function of the position of a provided as an exercise organ crank 1 shows Fig. 3 , The torque is constant between the positions φ _min and φ _max at the value M ₀ . This constant torque M ₀ corresponds to a certain force which the exercising person must exert on the crank 1 in order to be able to move it against the action of the motor 2 in one of the two possible directions of rotation. The setpoint for the position control of the crank 1 is the position φ _min , ie when the crank 1 is relieved by the exercising person, the position φ _{min is} approached and maintained. To move the crank 1 from there in the direction of the position φ _max , the exercising person must overcome the torque M ₀ .

At the position φ _max , the torque jumps almost abruptly to a much higher value M _max , whereby an upper mechanical stop is simulated by means of the motor 2 and its control. Likewise, the torque at the position φ _min in the case of applying the crank 1 with a torque in the opposite direction by the exercising person almost abruptly jumps to the negative value -M _max , whereby a lower mechanical stop is simulated. The range of movement of the crank available for the exercising person therefore lies between the position values φ _min and φ _max ·

True, is in Fig. 3 Assuming that the torque between the two end positions φ _min and φ _{max should be} constant M ₀ , but it would also be readily possible to specify here a position-dependent torque curve, for example in the form of a linear increase of the torque with the position φ.

It is also possible, instead of almost abrupt jumps in the torque at the two end positions φ _min and φ _max each provide a continuous change at a predetermined rate to the respective final value -M _max or M _max , whereby end stops are modeled with suspension. The rate of change may also be position-dependent, which corresponds to a nonlinear spring characteristic.

In addition, at the two end positions φ _min and φ _max in the transition region from the training torque M ₀ to the respective end value -M _max or M _max , a dependence of the torque on the rotational speed ω _I and thus on the speed of the crank 1 can be provided. This corresponds to the effect of a mechanical damper. With the invention, the equipment of end stops of an exercise organ with a spring-damper system can thus be emulated by a motor, the hardness of the spring or damping characteristic via the control unit 7, the card reader 10 or the bus interface 11 is adjustable.

The amount of the maximum torque M _max does not necessarily correspond to the maximum torque that the engine 2 can ever deliver to the crank 1 via the transmission 3, but is limited to a lower value in order to prevent a risk of injury. But he is so high that the achievement of one of the two end positions φ _min or φ _{max is} perceived by the exercising person in each case as a mechanical stop.

To the in Fig. 3 To realize torque curve shown above the position φ, a control device 5 is provided, whose internal operation is described below with reference to the block diagram of Fig. 4 is explained. In the Fig. 4 The right-hand components, namely consisting of the crank 1 and the transmission 3 machine, the motor 2, the frequency converter 4 and the rotation angle sensor 6 and the temperature sensor 12 correspond to those already based Fig. 1 mentioned components of the training device and therefore need no further explanation.

The control device 5 contains, as Fig. 4 reveals two control circuits in cascade structure, namely an inner loop for the speed ω and an outer loop for the position φ. The position in the form of a rotation angle φ and the rotational speed ω thus relate to the movement of the crank 1. To from the signal supplied by the sensor 6, which the rotation angle φ _M indicates the actual position φ _I and the actual speed ω _{I of} the crank 1, an evaluation device 13 is provided, in whose calculations in particular the reduction of the transmission 3 received.

The difference between a desired position φ _s and the actual position φ _I is fed to a first controller 14, which is preferably a proportional controller. In this case, the setpoint position φ _s corresponds to the lower end position φ _min in Fig. 3 The output variable of the controller 14 is a speed that is initially limited by a limiter 15 to a maximum value ω _max . This avoids that the crank 1 can reach the given by the engine 2 and the transmission 3 maximum speed, since in such extremely rapid movements of the crank 1, for example in the case of sudden relief by slipping of the exercising person from the crank 1, a high Danger of injury would be given. A second limiter 16 Also limits the angular acceleration to a maximum value α _max , to avoid excessive jerk when starting the crank 1, which, although less dangerous, but would be detrimental to the comfort of training. The two limiters 15 and 16 are basically optional but very useful from the point of view of safety and comfort.

At the output of the second limiter 16 is present as a signal a target speed ω _S , from which the calculated in the evaluation device 13 actual speed ω _{I is} subtracted. This is supplied to a preferably designed as a proportional / integral controller speed controller 17, which supplies a torque as an output variable. This is varied in a characteristic unit 18 as a function of the actual position φ _{I in} accordance with a predetermined function, for which purpose the characteristic unit 18 is supplied with the actual position φ _I as a further input variable. A preferred function with three constant sections and two equally high steps between these sections was previously described Fig. 3 explained.

Basically, by the characteristic unit 18 but also a different curve of the torque in dependence on the actual position φ _I than that of Fig. 3 be specified. In particular, the changes in the region of the two end positions φ _min and φ _max in the sense of a suspension could run continuously instead of suddenly. Furthermore, in the sense of damping, an additional dependence on the actual rotational speed ω _{I could also be} provided. The output variable of the characteristic unit 18 is the setpoint torque M _s for the crank 1.

Since the frequency converter 4 requires a setpoint torque M _M for the motor 2 as an input variable, the setpoint torque M _s for the crank 1 supplied by the characteristic unit 18 must be converted into said setpoint torque M _M for the motor 2 in a computing device 19. Initially, the reduction of the transmission 3 enters into this conversion. In addition, the computing device 19 has a memory in which tables are stored which describe the influence of further mechanical system parameters on the relationship between the two setpoint torques M _S and M _M. These include, for example, the weight of the crank, the friction losses of the transmission, moments of inertia of the transmission and the crank, the viscosity of the transmission oil and its temperature dependence.

The parameters which are included in the relationship between the two torques M _s and M _M are partly constant, but in some cases also dependent on motion variables and / or on the temperature. Therefore, the arithmetic unit 19 of the evaluation device 13 at least the actual position φ _I and the actual speed ω _{I of} the crank 1, optionally also additionally the actual angular acceleration α _I supplied, which is needed to take into account inertial effects. Furthermore, the measurement signal T of the temperature sensor 12 is also supplied to compensate for temperature influences.

In the course of the conversion of the setpoint torque M _{S of} the crank 1 into a corresponding payload torque M _{M of} the motor 2, the computing device 19 also carries out corrections which include additional mechanical and thermal influences which, apart from the gear reduction, are still converted into the conversion of the torque of the motor 2 into that enter the crank 1, compensate.

As far as the temperature is concerned, the compensation of their influence between the computing device 19 and a separate compensation device 20 or the frequency converter 4 may be divided, preferably in that the compensation of the temperature dependence of the motor 2 alone is already integrated in the frequency converter 4, or is perceived by a separate compensation device 20, since this temperature dependence is a motor-specific property. The presence of the compensation device 20 is therefore optional and depends on whether the used frequency converter 4 already provides an internal compensation of the motor temperature or not.

As far as the computing device 19 fulfills a temperature compensation, this is preferably limited to the temperature dependence of the motor 2 downstream mechanical components, in particular the transmission 3, in which, for example, the viscosity of the oil and thus the friction and the inertia depend on the temperature.

For example, it is conceivable to associate the computing device 19 with an operating time counter, to predict a mechanical wear of certain components dependent on the operating time on the basis of a mathematical model, and to set the desired torque M _M to compensate for the Wear phenomena to change over time accordingly.

It is also possible to make the length of the lever arm of the crank 1 to adapt to the body dimensions of the person exercising variable. In this case, the force exerted by the crank 1 in the tangential direction, which is the decisive criterion for the physiotherapeutic effect of training, depends on the lever length, so that the torque must be corrected accordingly to set a specific force with variable lever length. The body size can be communicated to the training device via the magnetic or chip card reader 10, whereupon the lever length is suitably adjusted via a servo motor and a specific one is selected by the computing device 19 from the data sets stored in its memory to take into account the set lever length.

The corrected from the torque M _{S of} the crank 1 and corrected target torque M _{M of} the motor 2 is supplied to the frequency converter 4 as an input variable. This regulates the engine 2 independently the previously explained principle of field-oriented control, so forms with the engine 2 a subordinate further control loop. For this he needs the measurement signal of the rotary encoder 6 on the shaft of the motor 2, which is fed directly to him. Since the control loop formed by the frequency converter 4 based on the measurement of an immediate state variable of the engine, namely the motor rotation angle φ _M , reacts this innermost control loop very quickly. This is a great advantage for the dynamic properties and the stability of the entire control. Frequency converters for three-phase motors, which operate on the principle of field-oriented control, are available in today's market for drive electronics. The application in a training device, however, is an innovation that is proposed here for the first time.

In the embodiment described above, the exerciser against which the user of the exerciser exerts a force during exercise is a crank. However, as one skilled in the art will readily appreciate, the exerciser may also take a variety of other forms, such as e.g. that of a stirrup, a handle, or one or two pedals. The present invention is not limited to a crank, but it includes all conceivable variants of an exercise organ, which is suitable to be acted upon by a person with muscle power. This includes, inter alia, training bodies that do not rotate, but perform a translational motion, which is then mechanically translated into rotation of a motor shaft. In this case, the terms used here of the rotation angle, the rotational speed and the torque correspond to a translational displacement or a translational speed or a force. Such modifications as would be obvious to one skilled in the art are intended to be included in the scope of the claims.

Claims (14)

1. Exerciser, more particularly an exerciser for strength training, with a torque-producing means having an electric motor (2) and a speed-reduction gear unit (3), the output of said torque-producing means interacting with at least one exercise unit (1) available to the user, wherein the electric motor (2) is in the form of a three-phase motor (2) associated with a frequency converter (4), by means of which frequency converter (4) the frequency and strength of the three-phase current supplied to the electric motor (2) are adjustable, wherein the frequency converter (4) is connected downstream of a closed-loop control means (5), characterized in that the motor (2) is associated with a rotation-angle sensor (6), the measured signal (ϕ_M) of said rotation-angle sensor (6) being supplied both to the frequency converter (4) and also to the closed-loop control means (5), wherein the frequency converter (4) is provided by the closed-loop control means (5) with a setpoint value (M_M) for the torque to be delivered by the motor (2), said setpoint value (M_M) including the measured signal (ϕ_M) of the rotation-angle sensor (6), wherein the frequency converter (4) adjusts the frequency and strength of the motor current according to the principle of field-oriented closed-loop control, and the closed-loop control means (5) has two cascaded control loops for regulating the position and rotational speed of the exercise unit (1), wherein the closed-loop control means (5) has an evaluation means (13) which, from the measured signal (ϕ_M) of the rotation-angle sensor (6), determines at least the position (ϕ_I) and rotational speed (ω_I) of the exercise unit (1) and supplies said values as actual values for the two control loops.
2. Exerciser according to claim 1, characterized in that the closed-loop control means (5) regulates the position of the exercise unit (1) to a setpoint value (ϕ_min).
3. Exerciser according to claim 2, characterized in that the position control loop is provided with a first limiter (15), which limits the setpoint rotational speed (ω_S) of the exercise unit (1) to a maximum value (ω_max).
4. Exerciser according to claim 3, characterized in that the position control loop is provided with a second limiter (16), which limits the rate of change of the setpoint rotational speed (ω_S) of the exercise unit (1) to a maximum value (α_max).
5. Exerciser according to any one of claims 1 to 4, characterized in that the rotational-speed control loop is provided with a transfer element (18), which varies the setpoint torque (M_S) of the exercise unit (1) according to a predetermined function depending on the position ((ϕ_I) and/or rotational speed (ω_I).
6. Exerciser according to claim 5, characterized in that the predetermined function includes increasing the value of the setpoint torque (Ms) of the exercise unit (1) at a predetermined rate in the case of increasing under/overstepping of at least one predetermined end position (ϕ_min; (ϕ_max) of the exercise unit (1).
7. Exerciser according to claim 5 or 6, characterized in that the predetermined function includes increasing the value of the setpoint torque (Ms) of the exercise unit (1) with increasing rotational speed (ω_I) in the case of under/overstepping of at least one predetermined end position ((ϕ_min; (ϕ_max) of the exercise unit (1).
8. Exerciser according to any one of claims 5 to 7, characterized in that the predetermined function includes limiting the value of the setpoint torque (Ms) to a predetermined maximum value (M_max).
9. Exerciser according to any one of claims 1 to 8, characterized in that the rotational-speed control loop is provided with a computing means (19), wherein said computing means (19) converts the setpoint torque (Ms) of the exercise unit (1) into a setpoint torque (M_M) of the motor (2) and adjusts said setpoint torque (M_M) as a function of mechanical and/or thermal operating parameters of the exerciser.
10. Exerciser according to claim 9, characterized in that the computing means (19) is supplied, as further input values, with movement values (ϕ_I, (ω_I, α_I) of the exercise unit (1) determined by the evaluation means (13) from the measured signal (ϕ_M) of the rotation-angle sensor (6), more particularly with the actual position (ϕ_I) and/or actual rotational speed (ω_I) of the exercise unit (1), wherein said movement values (ϕ_I, (ω_I, α_I) are included by the computing means (19) in the adjustment of the setpoint torque (M_M) of the motor (2).
11. Exerciser according to claim 10, characterized in that the angular acceleration (α_I) of the exercise unit (1) is one of the movement values that are determined by the evaluation means (13), supplied to the computing means (19) and included by the computing means (19) in the adjustment of the setpoint torque (M_M) of the motor (2).
12. Exerciser according to any one of claims 9 to 11, characterized in that the motor (2) and/or the gear unit (3) is/are associated with at least one temperature sensor (12), wherein the measured signal (T) of said temperature sensor (12) is supplied to the computing means (19) and/or to a separate compensating means (20) as an input value and is used there for the temperature-dependent adjustment of the setpoint torque (M_M) of the motor (2).
13. Exerciser according to any one of claims 9 to 12, characterized in that a compensating means, separate from the computing means (19), is provided for adjusting the temperature influence on the motor (2), said compensating means being integrated into the frequency converter (4).
14. Exerciser according to any one of claims 1 to 13, characterized in that the exercise unit is translationally movable, wherein means are provided for mechanically converting the translational movement into a rotational movement of the shaft of the electric motor, so that, at the exercise-unit end, the movement values are a distance, a velocity and a force instead of, respectively, a rotation angle, a rotational speed and a torque.

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