EP0865804B1 - Training apparatus for physically handicapped persons - Google Patents

Abstract

The training device has a crank with pedals or similar on its crank arms for connection to the feet or arms of the trainee, an electric motor connected to the crank, power electronics which drive the motor and an arrangement for regulating and/or controlling the crank's revolution rate. The control arrangement is designed to produce a revolution rate change delta n as a function of a torque MK on the crank where delta n = f(MK). A new revolution rate nnew is defined by nnew = nold + delta n, and the function delta n = f(MK) is different for previously defined ranges of the value of the torque MK.

Description

The invention relates to a training device with a crank for the disabled according to the preamble of claim 1.

State of the art

Exercise equipment with a crank are in diverse Embodiments have become known and regularly a mechanical structure with a large flywheel. The flywheel has the task of a balanced one To ensure rotation of the crank. Through this However, flywheel is the size and shape of a Training device determined in a disadvantageous manner. The default on the other hand, braking torque occurs with some Embodiments electronically. The braking torque represents a moment that counteracts the crank.

A movement trainer is disclosed in US Pat. No. 5,256,115, in which the flywheel is also electronically simulated to have the properties of a physically actually present flywheel. This means that a change in speed Δn can be described over the entire value range of a torque M _pedal on the pedals by the following function:
Δn = (M _pedal - M _B ) * A / J where M _{B is} an adjustable braking torque, A is a constant and J is an moment of inertia. A change in speed Δn, whether positive or negative, is therefore proportional to this over the entire value range of the torque on the pedal, since the other variables are adjustable, but then remain unchanged during many revolutions. This movement trainer is designed as a training device for competitive athletes and thus for people who have unimpaired mobility. A drive of the pedals generated by the movement trainer is not provided.

For patients with low residual strength, even with one-sided Paralysis (e.g. as a result of a stroke) however, the difficulty that any movement at all possibly even a round movement occurs. Such Most of the time, patients can only move part of a turn Exercise muscle strength. Therefore became active / passive trainers developed that have the ability to rotate continue even if the patient is no longer able is to apply torque to a crank.

The disadvantage of these devices, however, is that a Exerciser with little residual muscle strength through an active Join in, the rotational movement essentially not can influence.

Object and advantages of the invention

The invention has for its object a training device to provide for the disabled, with which on remaining movement options or residual muscle strength can be responded to in order to be as effective as possible To ensure the training process.

This object is solved by the features of claim 1.

In the subclaims are advantageous and expedient Developments of the training device according to the invention specified.

The invention is based on a training device with a crank for people with reduced mobility, pedals or the like being provided on the crank arms for connection to the feet or arms of the exercising person. Furthermore, the training device comprises an electric motor which is connected to the crank, power electronics and means for regulating and / or controlling the speed n of the crank. The essence of the invention lies in the fact that the power electronics are designed at least to drive the motor and the means for regulating and / or controlling the speed of the crank with regard to a change in the speed of the crank are designed such that with a previous energy supply E _K by a Torque M _K applied by the exerciser to the crank, which has led to an increase in speed, there remains an increase in speed Δn if the mechanical system present in the training device or electronically simulated immediately after the supply of energy has an amount of energy due to a braking torque M _B and / or due to frictional moments M _R and / or is withdrawn by the exerciser, which corresponds to a value which results from the energy supply E _K minus the energy loss during this energy supply due to a braking torque M _B and / or friction moments M _R. The main effect of this procedure is that a short-term speed increase that occurs due to a torque M _K applied by the exercising person only slowly subsides again. In conventional exercise equipment, the energy relationship described above is different in terms of speed. If such a system takes that portion of the energy which results from the difference between the energy supplied to the system by the pedaling person and the braking and / or frictional energy absorbed by the system, the crank rotates again at the speed as before the energy supply by the pedaling person (provided that a freewheel that does not take the crank in the pedaling direction is not taken into account).

In a particularly preferred embodiment of the invention the means for regulating and / or control are the speed for a speed change .DELTA.n as a function of a torque M _K at the crank according to .DELTA.n = f (M _K) designed, with a new speed n _new from the old speed n _old results from the relationship n _new = n _old + Δn, and the function Δn = f (M _K ) is different from M _K for certain predetermined value ranges.

In this way, different amounts of a change in speed during acceleration and deceleration of the crank can in particular be achieved in such a way that by selecting the function Δn = f (M _K ) in a certain range of the torque M _K z. B. a minimal torque applied by the patient is sufficient to bring about a strong increase in speed. In this case, pulse-like, oversized torque components transmitted from the patient to the crank can be “masked out”, so that a strong increase in speed is only permitted in a certain value range of the crank torque M _K.

Depending on the resolution of the speed control, changes in the speed can take place even in small angular ranges within one crank revolution. For example, in the case of discrete signal processing, the resolution is determined from the sampling time T when the torque or a parameter proportional to the torque is detected, the sampling time T being able to be significantly less than the period of a crank revolution. With such a scan z. B. the function for the speed change Δn can be written in the form of Δn = n (t _i ) - n (t _i-1 ) = F (M _K , t _i-1 ), where (t _i ) - (t _{i- 1} ) the time between two samples corresponds to the sampling time T.

In order to have a simple criterion for accelerating and decelerating the crank, it is proposed in an advantageous embodiment that a braking torque M _{B is} defined, which can also have the value "zero", with a value M _K > M _B of the torque on the crank, the means for regulating and / or controlling the speed n are designed for an increase in speed and for M _K <M _B for decreasing the speed, and the amount of the speed change caused by the means for regulating and / or controlling the speed Δn for M _K > M _{B is} greater than for M _K <M _B. This measure creates a kind of "residual muscle strengthening". This means that the speed, if the patient exceeds a predetermined braking torque, can cause a strong increase in speed, which drops only slowly when the braking torque is undershot. The advantage of this approach lies in the fact that, in addition to a continuous training process that is only possible with even tiny residual muscle strength, the positive psychological effect should not be underestimated. For the patient may realize for the first time that he has residual muscle strength and is also able to produce a round pedaling motion.

For a simple implementation of the invention, it is also proposed that the function of the speed change Δn follows the following law: Δn ∼ (M K - M B ) / k where "∼" stands for proportional and "k" is a factor that for M _K - M _B > 0 at least one value k = k _i and for M _K - M _B <0 at least one value k = k _j with k _i <k _j assumes that the speed increases more for M _K - M _B > 0 than it decreases for M _K - M _B <0. For such a regulation can be done in a particularly simple manner, for. B. program a microprocessor accordingly.

The development of the invention is particularly advantageous in that a base speed can be set by means of regulating and / or controlling the speed. This measure allows a patient to be moved passively without having to apply any torque to the crank itself. However, as soon as he B. overcomes a preset braking torque M _B , he can also increase the speed.

In the case of a basic speed specification, it is also favorable if the means for regulating and / or controlling the speed switch off the basic speed specification when a previously set limit torque M _{K, limit} on the crank occurs when the crank is driven by the engine. This avoids injuries that can occur when a rotation z. B. would be forced if the trainee cramps. In this context, it is further preferred if, when the basic speed specification is switched off, the means for regulating and / or controlling the speed are designed for slowly swinging the crank and resuming the basic speed. The pendulum process of the crank or a rocking movement of the crank can begin with a small angular deflection, which is increased until the rocking movement changes into a rotary movement again. An embodiment in which the means for regulating and / or controlling the rotational speed for starting in the direction opposite to the previous direction of rotation is designed is also favorable. This corresponds to the antagonistic principle for solving a spasm.

Furthermore, it is advantageous if the means for Regulation and / or control of the speed Crank rotation direction z. B. predefined for a basic speed can be. For different directions of crank rotation trains different muscle areas on the patient become.

drawings

An embodiment of the invention is as follows and is shown in the description below under Details of further advantages and details explained.

The figure shows the block diagram of a preferred circuit to control or regulate an inventive Training device.

Description of the embodiment

The figure is intended to illustrate the function of a training device according to the invention on the basis of a schematically illustrated block diagram of a circuit 1 for control and / or regulation. In circuit 1, the flow of information is represented by arrows drawn in solid lines, whereas the flow of energy is to be symbolized by arrows drawn in bold. The circuit according to the invention comprises an operating unit 2 via which a basic speed n ₀ , a braking torque M _B , a maximum permitted torque on the crank M _{K, max} and various other parameters can be entered. These values are passed on to a general control unit 3 in accordance with the arrows labeled n ₀ , M _B , M _{K, max} and 100 in circuit 1. For information and adaptation purposes, the general control unit 3 is also supplied with a signal 101 that the actual rotational speed corresponds to the crank (not shown) connected to an electric motor 4, which is used to hold the feet of a trainee. In addition, the general control unit 3 also receives a signal 102 for information and, if necessary, adaptation purposes, which corresponds to the actual torque M _K on the crank. The torque signal 102 is further fed to a control unit 5 for the speed change Δn and a control unit 6 for the speed and the torque on the crank. In addition to the general control unit 3, the speed signal 101 also supplies the control unit 6 for the speed and the torque.

A core element of the circuit 1 is the control unit 5 for the speed change Δn. For example, a change in speed Δn results from the context
Δn = (M _K - M _B ) * A / k. Where M _{K represents} the torque on the crank, M _B the braking torque, A a factor and k a value dependent on the difference value M _K - M _B. For M _K - M _B> 0, a value k = k _i and for M _K - M _B <0, a value k = k _j used, where k _i <k _j. As a result, if the braking torque M _B , which the control unit 5 receives from the control unit 3, is exceeded on the crank, a speed increase Δn _i occurs which is greater in amount than a speed decrease Δn _j when the resulting torque M _K - M _B is negative again. In other words, the amount for Δn for M _K - M _B > 0 is greater than for M _K - M _B <0. The speed change Δn is added to an old target speed n _old in the control unit 3 and thus results in the new target speed n _new .

If a basic speed specification is active, the basic speed n ₀ entered by the control unit 2 is used as the basis for this calculation. That means for a first speed change Δn the new target speed n _new results from the sum of n ₀ and Δn. This value then serves as the old target speed for the next calculation of the new target speed. In the event that there is a negative speed change Δn, the speed does not fall below the value n ₀ due to the basic speed setting.

The respective current target speed n _new is passed on to the control unit 6 for the speed and the torque, which, by processing the speed signal 101, transmits a manipulated variable 103 to power electronics 7, which then energize the electric motor 4 connected to the crank in order to achieve the target speed.

In order for a basic speed set by the basic speed n ₀ injury in a training person, for his feet. B. are connected to the pedals of the crank to avoid, a maximum crank torque M _{K, max} can be set on the control unit 2 that passes through the control unit 3 to the control unit. If the torque signal 102 exceeds this permissible torque, the basic speed specification is switched off and the crank comes to a standstill. The control unit 3 then starts to run up from standstill. With the appropriate presetting, the direction of rotation can be changed. This is useful, for example, when the torque limitation is used for spastic disabled people in cramped conditions. The opposite start of the crank corresponds to the antagonistic principle of the cramp solution.

In the present exemplary embodiment, the control units 3, 5, 6 are implemented in a microcontroller 8, which implements digital signal processing. For this purpose, the speed signal 101 or the torque signal 102 is sampled with a sampling frequency f = 1 / T and fed to the microcontroller 8. Conveniently, a speed change .DELTA.n and a new target rotational speed from n _recalculated after every sampling time T. Provided that the sampling time T is much smaller than the period of the rotary movement on the crank, speed changes are made during small angular rotations of the crank. This creates a highly dynamic relationship between a moment M _K at the crank and a subsequent change in speed.

By means of the procedure according to the invention, a training device is provided for movement-impaired persons, with which a continuous training sequence largely determined by the handicapped person himself can be guaranteed even with the smallest residual muscle forces. If the patient has only very small residual muscle forces, the braking torque M _B can be reduced to such an extent that the value M _K - M _B becomes positive even with a very small torque on the crank, but causes a large speed change by means of a correspondingly small value for k . As soon as the patient is no longer able to apply torque to the crank, the speed does not drop with this small value for k. This is because, according to the invention, a large value for k can be used for M _K - M _B <0, so that the speed of rotation until the next force pulse of the patient, with which the value M _K - M _B becomes positive again, has dropped only slightly. In this way, tremendous psychological motivation can be created for the disabled, who may feel for the first time that they still have residual muscle strength.

Claims (9)

1. Training apparatus with a crank for physically handicapped persons, pedals or the like for connection to the feet or arms of the person training being provided on the crank arms, and with an electric motor (4) connected to the crank, an electronic power unit (7), and with means for regulating and/or controlling the speed of the crank, characterised in that the electronic power unit is designed at least to drive the motor and the means for regulating and/or controlling the speed of the crank are designed with a view to changing the speed of the crank in such a way that with a previous supply of energy E_K, owing to a torque M_K at the crank applied by the person training, which has led to an increase in speed, there is a change in speed Δn if immediately after the supply of energy a quantity of energy is taken away from the mechanical system existing or reproduced electronically in the training apparatus owing to a braking moment M_B and/or owing to frictional moments M_R and/or owing to the person training, which quantity of energy corresponds to a value which is produced from the supply of energy E_K minus the loss in energy during this supply of energy owing to a braking moment M_B and/or frictional moments M_R.
2. Training apparatus according to claim 1, characterised in that means (1) for regulating and/or controlling the speed are designed for a change in speed Δn as a function of a torque M_K at the crank in accordance with Δn = f(M_K), a new speed n_new being produced from the old speed n_old in accordance with the equation n_new = n_old + Δn, and in that the function Δn = f(M_K) is different for specific, previously determined value ranges of M_K.
3. Training apparatus according to claim 2, characterised in that a braking moment M_B is defined, the means (1) for regulating and/or controlling the speed being designed for an increase in speed for a value M_K > M_B and for reduction in speed for M_K < M_B, the value for the change in speed Δn being greater for M_K > M_B than for M_K < M_B.
4. Training apparatus according to claim 3, characterised in that the function of the change in speed Δn obeys the following law; Δn ∼ (MK - MB) / k, wherein "∼" means proportional and k is a factor which for M_K - M_B > 0 at least assumes a value k - k_i and for M_K - M_B < 0 at least assumes a value k = k_j, where k_i < k_j, so the speed increases more for M_K - M_B > 0 than it decreases for M_K - M_B < 0.
5. Training apparatus according to any one of the preceding claims, characterised in that a basic speed can be adjusted by the means (1) for regulating and/or controlling the speed.
6. Training apparatus according to claim 5, characterised in that the means (1) for regulating and/or controlling the speed switch off the basic speed preset when an adjustable limit moment M_K,limit occurs at the crank in a crank driven by the motor.
7. Training apparatus according to claim 6, characterised in that when the basic speed preset is switched off the means (1) for regulating and/or controlling the speed are designed for slow oscillation of the crank and resumption of the basic speed.
8. Training apparatus according to claim 6 or 7, characterised in that the means (1) for regulating and/or controlling the speed are designed to start in the direction counter to the preceding direction of rotation.
9. Training apparatus according to any one of the preceding claims, characterised in that the direction of rotation of the crank can be predetermined by the means (1) for regulating and/or controlling the speed.

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