CA2853540A1 - Exercise machine - Google Patents

Abstract

An exercise device comprising a biasing member to be moved by the force of a user, an electric actuator (1) having a movable portion, the biasing member being bonded to the movable portion, and the biasing member being adapted to move the moving part, a computer (12) capable of generating a control signal of the electric actuator, an acceleration sensor coupled to the moving part for measuring the acceleration of the moving part and for transmitting the acceleration measured at the computer (12), the electric actuator being adapted to exert a force on the biasing element via the moving part in response to the control signal, characterized in that the computer (12) is adapted to generating the control signal as a function of the acceleration measured so that the force exerted by the electric actuator (1) comprises a substantial artificial inertia contribution proportional to the acceleration measured by the acceleration sensor.

Description

EXERCISE MACHINE
The invention relates to the field of exercise machines. More particularly, the invention relates to the field of electric motorization designed to develop or reconstruct the musculature of a user and allowing especially the sports training or the re-education of the muscles of a user.
Among the machines for muscular exercise, there are in particular weights and inertia machines.
Weight machines operate on the principle of cast iron masses or other material that a user moves by providing an effort to counter the weight of the masses cast. These machines include presses, free bars, dependent devices guided etc.
Inertia machines work differently. These consist of example to set in motion a cast iron disc around an axis of rotation.
The user must therefore provide an adequate effort to overcome the inertia of the machine.
Some machines work with the principle of moving a fluid with a system fins.
Although the fluid put in motion has an inertia, in these machines the user must overcome mainly the viscous friction induced by fluids.
Other machines use the principle of eddy current system to generate these viscous friction.
These machines producing viscous friction are in particular the machines Of type rower or indoor bike.
According to one embodiment, the invention provides an exercise device comprising a biasing element intended to be displaced by the force of a user, an electric actuator comprising a movable part, the element of solicitation being bound to the moving part and the biasing element being able to move the moving part, a computer capable of generating a control signal of the electric actuator and an acceleration sensor coupled to the moving part for measuring the acceleration of the mobile part and to transmit the measured acceleration to the computer, the electric actuator being able to exert a force on the element of solicitation by via the moving part in response to the control signal, in which the computer is able to generate the control signal in function of the acceleration measured so that the force exerted by the actuator electric features

2 a contribution of artificial inertia substantially proportional to measured acceleration by the acceleration sensor.
According to one embodiment, the computer is able to generate the signal of command as a function of measured acceleration and a coefficient of proportionality and calculator is able to vary the coefficient of proportionality in function of at least one parameter chosen from the position, velocity and acceleration of the part mobile.
According to one embodiment, the computer is able to generate the signal of control so that the force exerted by the electric actuator comprises a additional load contribution having a predetermined direction.
According to one embodiment, the computer is able to generate the signal of control so that the artificial inertia contribution is oriented in the same sense that the predetermined direction contribution when measured acceleration is in the sense opposite of the predetermined meaning contribution.
According to one embodiment, the computer is able to generate the signal of order to cancel the artificial inertia contribution when acceleration measured is in the same direction as the predetermined direction contribution of actuator electric.
According to one embodiment, the connection between the biasing element and the part mobile has a speed reducer to increase the force of the motor.
Generally, such a reducer generates an additional real inertia for the user who actuates the solicitation element. According to one embodiment, the inertia contribution Artificial exerted by the electric actuator can compensate all or part of inertia additional actual generated by the gearbox.
According to one embodiment, the device comprises a speed sensor able to measure the speed of the moving part and the calculator is able to generate the signal from control so that the force exerted by the electric actuator comprises a viscous friction contribution substantially proportional to the speed measured by the speed sensor.
According to one embodiment, the electric actuator is a linear motor.
According to one embodiment, the electric actuator is a rotary motor in wherein the movable portion comprises a rotor of the rotary motor.
According to one embodiment, the acceleration sensor comprises:
a position encoder coupled to the moving part for measuring the position of the part mobile, the position encoder generating a position signal,

3 branching elements adapted to derive the position signal for determine the acceleration of the moving part.
According to one embodiment, the exercise device is selected from the including rowing machines, indoor bicycles, lifting bars and the devices of guided load.
According to one embodiment, the movable part comprises a mounted motor shaft in rotation, the motor shaft is coupled to a gearbox, a pulley is coupled to the reducer, a cable is attached to the pulley at one end of the cable, the cable is attached to the element handling at a second end of the cable and the cable is suitable for curl up on the pulley.
According to one embodiment, the exercise device comprises an interface man-machine allowing a user to set a coefficient of proportionality between measured acceleration and calculated artificial inertia contribution.
According to one embodiment, the calculator is able to calculate the force at exercise way that the force to be exerted by the electric actuator comprises a contribution of additional load having a predetermined meaning, the human interface machine allowing a user to adjust the additional charge contribution regardless of coefficient of proportionality.
According to one embodiment, the man-machine interface allows a user to adjust the additional charge contribution to a zero value.
According to one embodiment, the biasing element is movable in a vertical direction and that the calculator is able to calculate the force at exercise in the absence of force exerted by the user so that the force to be exerted by the electric actuator has a default load contribution that compensates for a dead weight of the element of solicitation without causing spontaneous displacement of the element of solicitation in the absence force exerted by the user.
According to one embodiment, the invention also provides a method of control of an exercise device comprising:
measure the acceleration of a moving part of an electric motor in response to strength of a user exercised on a solicitation element related to the party mobile, generate a control signal according to the measured acceleration and control the electric actuator with the control signal so that the strength exerted by the electric actuator on the biasing element by through the

4 moving part has a contribution of artificial inertia substantially proportional to measured acceleration An idea underlying the invention is to simulate on an exercise machine, during the use of the machine by a user, a different inertia of the real inertia of the exercise machine using an electric actuator.
An idea underlying the invention is to design a machine that allows to vary weight and inertia independently of each other.
Some aspects of the invention start from the idea of simulating, on the machine of exercise, extra weight using the electric actuator.
Some aspects of the invention start from the idea of simulating, on the machine exercise, additional friction using the electric actuator.
Some aspects of the invention start from the observation that combining the exercises of type inertia characteristics of inertial machines and the exercises of type weight features of weight machines in a single machine allows a gain of place important and a less expensive investment.
Some aspects of the invention start from the idea of generating forces inertia during certain phases of muscle exercise performed by the user and to cancel these forces of inertia in the other phases of the exercise muscular.
Some aspects of the invention start from the idea of generating forces of inertia without fixed charge to create muscular solicitations specific to the reversal of movement of a mass launched on a substantially horizontal trajectory, in particular the inversion of the movement of a runner.
The invention will be better understood, and other purposes, details, features and advantages of it will become clearer in the description next several particular embodiments of the invention, given only as illustrative and not limiting, with reference to the accompanying drawings.
On these drawings:
Figure 1 is a schematic representation of an exercise device comprising an engine.
FIG. 2 is a schematic representation of the control system of the motor shown in Figure 1.
Figure 3 is a graph of position and acceleration based of time of the handle described in Figure 1 corresponding to a manipulation by the user.

= Figure 4 is a graph of the force exerted by the engine during a manipulation of the device of Figure 7.
= Figure 5 is a graph of the force exerted by the motor during the manipulation of the device according to Figure 3 corresponding to a first type

5 exercise.
= Figure 6 is a graph of the force exerted by the motor during the manipulation of the device according to Figure 3 corresponding to a second type Exercise.
= Figure 7 is a schematic representation of a variant of device Exercise.
= Figure 8 is a schematic representation partially in section a exercise device comprising a motor according to another embodiment.
= Figure 9 is a schematic functional representation of a system of motor control shown in Figure 8.
= The figure 10 is a schematic representation of an inversion exercise of the movement of a runner.
= Figure 11 is a graphical representation of the operation of a hysteresis comparator which can be used in the control system of Figure 9.
Figures 1 and 2 illustrate an exercise device in which can to be put in implementing control methods according to the invention. With reference to the Figure 1, the exercise device comprises an electric motor 1 which can lead to rotating a tree 2 and exert a torque on the shaft 2. A pulley 3 is tightly mounted on the tree 2. A cable 4 is fixed at its first end in the groove of the pulley 3. This cable 4 can wind up in the groove around the pulley 3. At the second end 5 of the cable is fixed a handle 6 by through which a user can influence the device with his strength muscle when practicing muscle exercises.
The motor 1 comprises a position encoder 10 which measures the position of the tree 2. The position is transmitted to an electronic card 7 in the form a signal from position 9. This electronic card 7 is adapted to receive this signal of position and uses the position signal 9 to generate a control signal. Thanks to this signal order, the electronic board 7 controls the torque generated by the engine 1 to control strength exerted by the engine 1, which is transmitted at the level of the handle 6 by intermediate pulley 3 and cable 4. For this, the electronic card 7 transmits the signal from

6 motor control 1 via the connection 8. This control signal is received by a organ integrated power supply in the motor 1 which, from this signal of command, provides a certain current to the motor 1. The current supplied by the power supply thus induces a torque on the moving part 2 and therefore via the pulley 3 and the cable 4 a strength on the handle 6. The force exerted by the motor 1 is substantially proportional to current supplied by the power supply unit to the motor 1.
Many control methods can be implemented in such a way.
device to produce different muscular stresses. A first example is from simulate the presence of a predetermined mass suspended on a cable, namely that the couple motor exerts on the handle 6 a constant load as to the direction and intensity.
When a user manipulates the handle 6 during an exercise this one opposes the force of the motor 1 with the help of its muscular strength. For example, at a practicable exercise with this device, a user is positioned above of the device and pulls the handle 6 from a low position to a high position at using his hands. When moving upwards, the user must defeat the force directed downwards by the motor 1 on the handle 6. When the handle 6 comes into position, the user performs the reverse movement and returns the handle 6 towards the low position while still being constrained by the same force submitted in the same direction by the engine 1. During the descent, the user accompanies and brakes moving the handle down. The exercise device thus simulates a mass to be alternately raised and rested by the user During this exercise, the position signal is transmitted continuously to the electronic card 7 which calculates and transmits to the motor continuously the signal from corresponding order. Thus, the device controls the effort generated by the engine 1 all throughout the exercise.
However, a slight shift may be present between the moment the encoder transmits the position and the torque exerted by the engine 1 because of the time of response from motor 1 to the control signal and the response time of the electronic card

7.
With reference to FIG. 2, the motor control means now go to be described more precisely with reference to a second example.
The electronic card 7 here comprises a microprocessor 20. An encoder position 10 measures the position of the motor shaft 2, this position is encoded in one signal from position that is transmitted via the connection 38 to the microprocessor 20. Thus, in a mode of realization this measurement can be issued every 30ms and preferably every 5 ms.

In this microprocessor 20, the position signal is transmitted to an organ of derivation 13 via the connection 18. The branch member derives the position signal generating a speed signal which is transmitted to a second branch member 14 via the connection 15.
The second branch member derives the speed signal thereby generating a signal acceleration. The acceleration signal is transmitted via the connection 17 to a module of calculation. Furthermore, the position signal and the speed signal are respectively transmitted to the calculation module 12 via the connections 11 and 16. The module of calculation 12 calculates the control signal to be supplied to the motor and transmits it to the motor via the connection 19.
More specifically, the control signal is calculated from the acceleration of so that the force exerted by the motor 1 on the handle 6 comprises the load directed to the down and a predetermined artificial inertia.
For this, the calculation module 12 takes into account the accumulation of the torque exerted by the motor 1 and the inertia of the rotating parts of the device connected to this engine what are the tree 2, the pulley 3, the cable 4 and the handle 6.
Indeed, when a user manipulates the handle 6:
mrxY = Fm + Fs (1) Where F5 is the force exerted by the user on the handle 6, Fm is the force exercised by the motor 1 on the handle 6 and controlled by the calculation module 12, mr is the inertia moving parts brought back to the handle 6 and the mass of the handle 6 and is the acceleration of the handle 6.
Equation (1) corresponds to the fundamental principle of the dynamics applied to a system in translation. However, those skilled in the art will understand that the exercised couples on a rotating system can be modeled similarly.
The force exerted by the engine Fm is composed of two induced components by the control signal: a fixed component Fch representing the load and a component proportional to the acceleration Fi which represents the artificial inertia.
So :
Fm Fch + Fi (2) Or the force Fi is defined according to a coefficient of proportionality k:
= ¨kxy (3) The coefficient k is a parameter that is programmed in the calculation module 12.
Equation (1) can be rewritten:
(m, + k) xy Fch Fs (4) In this way, if the coefficient of proportionality k used for produce the control signal is negative, ie ¨m, <k <0, the device simulates a inertia

8 lower than the actual inertia of the device, that is to say the inertia of the parts rotary device. If the coefficient of proportionality k is positive, the device simulates an inertia more important than the actual inertia of the device.
The user, through a user interface not shown can modify the values of the fixed component Fch and the factor of proportionality k and so determine the type of effort with which he wishes to practice. So, he is possible to do vary independently the load of inertia. A wide range of type exercises muscle can be offered to the user.
The user interface is connected to the calculation module 12 and is suitable for to receive data on position, speed, acceleration or information calculated from these data, for example, the effort provided or the power expended. These data and information is calculated by the calculation module 12 from the signals acceleration, speed and position transmitted to the calculation module 12 respectively by the connections 17, 16 and 11. With this data and information, the user interface can solicit sensorially the user by displaying this information. The user can this way to follow the level of his effort during his physical exercises. However, these stresses can be of different natures, solicitations are by example conceivable. In addition, the user interface includes ordered allowing the user to vary the values of the fixed component Fch and the factor of proportionality k, preferably independently of one another. These bodies of order are for example buttons on the user interface corresponding to fixed component pair Fch and proportionality factor k predetermined. These couples thus define several types of exercises. A storage organ, for example a memory in the calculation module 12, makes it possible to store this information and data.
Thanks to this storage, the user can follow the evolution of his performances during the time.
With reference to FIGS. 3, 5 and 6 several particular examples of exercises who can be produced by the device presented above will be described.
FIG. 3 represents the position of the handle 6 along the z axis of the figure 1 and the acceleration of the handle 6 as a function of time during the solicitations of traction of the handle shown with reference to Figure 1. The dashed curve 21 represents the position of the handle that is measured by the position encoder 10. The curve continue 22 represents the acceleration corresponding to the position curve 21. By convention, we have WO 2013/06099

9 the z-axis downwards in Figure 1. The point 24 of the curve of position 21 corresponds so when the handle 6 is in the low position and the point 23 corresponds at the position high of the handle.
For purposes of illustration between point 23 and point 25, the position 21 is substantially sinusoidal. Thus acceleration also forms, along of this period, a sinusoidal curve. Subsequently, the position curve is no longer sinusoidal and therefore the acceleration is no longer sinusoidal.
FIG. 5 represents the force opposed by the motor 1 to the user in function time for the same time interval as Figure 3. Curve 28 is constant at level of a threshold 26. Indeed, Figure 5 corresponds to a first exercise where the module calculation provided a control signal to the motor so that the force opposite to the user is constant in time. For this, the calculation module produces a signal control inducing a force having a load component equal to threshold 26 and a component zero inertia. In this exercise, the user therefore only objects to a fixed charge and to the real inertia of the system.
Figure 6 shows a second exercise that partially uses the principle of first exercise presented with reference to Figure 5. Curve 40 represents the force generated by Engine 1 during this exercise. It has two phases: a high phase 31 during which the curve is constant at the threshold 27 and a phase low during which curve takes the form of the acceleration curve at the level of the threshold 27. In effect, the user is subjected to a load force corresponding to the threshold 27 when measured acceleration is positive, ie here during phases high 31 of the manipulation of the handle where the handle is close to its high position 23.
The user is however subject to additional inertial effort oriented in the same direction that force when the measured acceleration is negative, ie during a low phase 29 when the handle reaches the low position 24 and the user decelerates the descent and then accelerates to pull the handle towards the position high 23. This low phase corresponds to the phase 30 during which the acceleration is negative. Of this way, the user is subjected to additional artificial inertia when he arrives low position and wishes to raise the handle to the up position, ie say at the moment where his muscular solicitation is the most intense. Thus, the device exercise helps produce an additional solicitation that opposes the user during an inversion of the sense of the movement of this user.

For the implementation of the second exercise, the calculation module 12 applies a proportionality coefficient k determined as follows:
Siy> 0, k = 0 (5) If y <0, k = + ko, ie k> 0 (6) Where ko is a predetermined positive constant.
The exercises described above are given for illustrative purposes. In particular, the calculation module can control the coefficient of proportionality k of multiple ways. AT
For example, the calculation module can vary the coefficient of proportionality in depending on the position or speed of the handle. So, in a variant, the device

Exercise produces an additional inertia component when the handle reaches a certain position. In a variant of the exercise device, this component of inertia additional is added when the speed is in a particular direction. Of this way a multitude of interesting exercises for muscle development can to be produced.
This makes it possible to solicit the muscles of the user more intense when in a particular position.
In a variant of the device shown in FIG. 1, the driving shaft 2 is connected to a speed reducer having a reduction ratio r. The presence of such reducer allows generate relatively large forces while reducing the size of the engine, miniaturization purposes of the device. The pulley 3 is fixed on a tree of output of the reducer.
In this variant, the presence of a reducer greatly increases the inertia real parts motor 1 to the handle 6. The actual inertia of the device is also increased by the reduced inertia of the rotating parts of the gearbox. inertia engine and Reducer reduced to the output of the hot reducer can be written:
Jtot = hed r2imot (7) with the inertia of the reducer'red and the real inertia of the Jmot engine. So, if The report , reduction is important, The actual inertia of the system is greatly increased. So, the use of a proportional factor k negative allows in this variant to compensate all or part of the inertia induced by this reducer. This compensation is all the more specifies that the acceleration that is measured to generate the force of inertia artificial is the acceleration of the motor shaft 2, so that this measure takes into account the effect of reduction, the effect of increasing by the ratio r the acceleration at level of the tree motor 2 with respect to the acceleration exerted on the handle 6.
The very simple exercise device described with reference to FIGS. 1 and 2 given for illustrative purposes, the invention is therefore in no way limited to this type of exercise device.

11 In particular, the invention can be adapted to any type of exercise machine soliciting any part of the body. For example, the invention may be adapted for constitute a rower-type device, an exercise bike or a lifting.
Referring to Figure 7 there is shown an exercise device 50 for exercise the muscles of the arms in traction and thrust in which methods of order according the invention can be implemented.
The device 50 has two levers 53 that can be moved alternatively forwards and backwards by a user. The levers 53 are coupled each to an electric motor 54 which is controlled by the device of order 55. According to one embodiment, the motors 54 are controlled so as to generate a strength represented by the curve 33 of Figure 4. For the sake of simplification, the rotary motion levers are approximated in a linear motion along the x-axis.
Thus, FIG. 4 represents the effort opposed to a user in the context of exercise device shown in Figure 7. Curve 33 represents the force generated by the motor and has a value proportional to the acceleration curve 30. Suppose that a user performs solicitations the lever 53 so that the measured position and acceleration are the same as in Figure 3, the x axis replacing here the z axis. In this type of exercise, the control device 55 submits a control signal to the 54 engines that does not induce a charge component. Only a component of inertia artificial is produced by the engines 54. Thus, the effort made by the user is proportional to acceleration and therefore corresponds to a simulated inertia without load which is better than the actual inertia of the device.
This type of stress with artificial inertia without load extra is also interesting in an exercise machine soliciting the muscles of the legs. Indeed, the muscular strain produced by the engine when ordered from this way corresponds substantially to the muscular stress required to reverse movement of a runner on a horizontal ground. Such an exercise is illustrated on the figure 10.
In Figure 10, the runner 34 is initially running high speed in the direction of the x-axis, as schematically represented by the vector of speed 35. At the end of the exercise, the runner 34 is running at high speed in the opposite direction to the axis x, as shown schematically by the velocity vector 36. At during the exercise, the runner 34 had to slow down his movement until the stop, happened by example at point x0, then re-accelerate in the other direction. The muscles of the runner 34 have so been solicited during this exercise primarily to overcome inertia of the rider himself

12 same, oriented along the x axis. The force of gravity being perpendicular to movement she does not create any particular muscle solicitation in this exercise, that is, to say that the Muscle stress specific to exercise is a solicitation of pure inertia. The exercise machine programmed to produce this type of solicitation is all the more advantageous that this race reversal situation is very common in sports of ball, for example rugby or football.
Similarly, a control program associating the force of inertia artificial with a constant load allows to produce a muscular solicitation analogous to the completion of the same exercise on a sloping ground.
A device for simulating a viscous friction force extra will now be presented. The device is similar to described device with FIG. 7 and comprises a microprocessor having the same structure as the microprocessor 20 of the control system depicted in FIG.
exercised by the motor has three components here. The first two components correspond to the load component and the inertia component described above. The third component is a component of viscous friction. So :
= Fm - = Fch + Fi + Ff (8) Where the force Fr, corresponding to the viscous friction component, is defined according to a coefficient of proportionality k2 and according to the speed y of the handle:
Ffv = k2 XV (9) The speed is determined by the calculation module 12 thanks to a signal of speed which is transmitted to the calculation module 12 via the connection 16.
So, when the user moves the levers in one direction, the motor generates a torque on the lever including the viscous friction component proportional to the speed of movement of the lever in addition to a component of inertia. This component of viscous friction causes an additional solicitation that opposes the sense of user's movement. In this way, the device simulates a viscous friction can be produced by a machine comprising a finned system.
The coefficient k2 can be a constant stored in the memory of the microprocessor 20. In the same way as the inertia component, the module Calculation 12 can control the coefficient of proportionality k2 in multiple ways. AT
as an example, the calculation module can vary the coefficient of proportionality k2 in function of the position of the handle.

13 With reference to FIGS. 8 and 9, another machine will now be described.
60 using an electric motor. The machine 60 has a shape relatively similar to a weight machine known as the squat machine (from English for squat). But it can provide a range of solicitations much more muscular extended.
The structure of the machine comprises a metal base 61 placed on the ground, shown in section 8, and a guide column 62 fixed vertically to the base 61. The upper surface of the base 61 constitutes a platform 68 intended for welcome an athlete, for example in standing position as illustrated in ghost line. A carriage 63 went up to sliding on the column 62 by guide means, not shown, of way to vertically translate along column 62. According to a method of realization, the carriage 63 is a four-sided structure that completely surrounds column 62, one of which and the other having a square section. The carriage 63 carries gripping rods 69 which extend above platform 68 and are intended to be in touch with the athlete, for example at the level of his shoulders or his arms or legs according to the desired exercise.
A transmission belt 64 is mounted in the column 62 and extends between a Crazy pulley 65 pivotally mounted at the top of column 65 and a pulley motor 66 pivotally mounted in the base directly above the column 62. The belt 64 is a toothed belt that makes a round-trip closed loop between pulleys 65 and 66 of to be coupled without slippage to the drive pulley 66. The carriage 63 is linked to one of the two branches of the belt 64, for example by means of rivets 67 or other means of attachment, so that it is also coupled without sliding on the pulley motor 66, any rotation of the pulley 66 translating into a translation vertical carriage 63. Preferably, the belt 64 is balanced with an AT10 toothed belt.
which both ends are attached to the carriage 63, so as to close the buckle at the of the trolley 63.
A motor unit 70 is housed in the base 61 and coupled to the drive pulley 66 by through a speed reducer 71. More specifically, the reducer speed 71 comprises an input shaft 72 coupled without sliding to the drive shaft of the engine group 70, which is shown in more detail in FIG. 9, and an output shaft 73 which carries the pulley 66. The speed reducer 71 imposes a reduction ratio r enter here rotation speed wl of the shaft 72 and the rotation speed w2 of the shaft 73, namely wl / w2 = r. According to embodiments, the reduction ratio r is chosen between 3 and 100, and preferably between 5 and 30.

14 The machine 60 also comprises a control console 74 which can be integral with the base 61 or independent thereof. In addition, a cable power supply 75 leaves the base 61 to be connected to the power grid. The machine 60 does not does not require a exceptional electrical power and can therefore be powered by a network domesticated current.
FIG. 9 represents more precisely the motor group 70 and its unit of control 80, which is also housed in the base 61. The power unit 70 has a electric motor 76, for example an autopilot synchronous motor, and a current dimmer 77 which controls the supply current 78 of the motor 76.
It is recalled that the synchronous motor autopilot has a rotor flow constant.
This flux is created by permanent magnets or coils mounted in the rotor, while the variable stator flux is created by a three-phase winding allowing orient it in all directions. The electronic control of this engine consists in control the phase current waves so as to create a rotating field, always ahead of 90 on the Magnets field, so that the torque is maximum. In these circumstances, the engine couple on the motor shaft 2 is proportional to the stator current. This current is precisely controlled in real time by the control unit 80 via the dimmer current 77.
For this, the control unit 80 comprises a low-level controller 81, for example of FPGA type, which receives the position signal 83 from the encoder of position 84 of the motor shaft 2 and performs calculations in real time from the signal of position 83 for determine the instantaneous values of the position, speed and the acceleration of the tree 2. The position encoder 84 is for example an optical device which provides two square signals in quadrature according to the known technique.
The high-level controller 82 has a memory and a processor and executed complex ordering programs from the information provided in real time by the low-level controller 81. Possible control programs have been described higher with reference to Figures 3 to 6.
The control console 74 is connected to the high-level controller 82 by a TCP / EP 85 link, wired or wireless, and includes an interface allowing the athlete or his trainer to select prerecorded exercise programs or adjust precisely and in a personalized way the parameters of such a program.
In the example shown, the interface is a touch screen 86 which has a cursor 87 to adjust the value the load F ch along a predetermined scale, for example 0 to 3000 N, and a slider 88 to set the value of the coefficient k along a predetermined scale, that is to say, the artificial inertia force F.
Depending on the exercise program performed, the high-level controller 82 processes the information provided in real time by the base controller.
level 81 and calculates the 5 couples to be exercised by the power unit 70. The base controller level 81 generates a control signal 90 corresponding to this instantaneous torque and transmits the signal 90 to the current controller 77, for example in the form of a voltage of ordered analogue between 0 and 10V. Alternatively, a CAN digital interface can also be used.
10 The control programs to simulate different exercises can to be very numerous. Preferably, whatever the detail of the program, it is always the athlete who drives the machine 60 and the machine 60 that reacts to the solicitation by the athlete on the gripping bars 69. For this, it is preferable that the machine 60 can respond quickly to changes in direction imposed by the athlete despite friction

15 that inevitably exist in such a mechanical system.
For this, according to one embodiment, the high-level controller 82 sets in a friction compensation algorithm that will now be Explain.
We denote by mc the mass of the carriage 63. We note Fc = mc.g, the force that must impose the motor 76 on the belt 64 to compensate for the weight of the carriage 63 without the user does supports no charge. The algorithm uses parameters a and b defined by the fact that if the motor 76 applies Fc + has the carriage 63 is at the limit of movement in the direction positive, upwards, and if the motor 76 applies Fc -b the carriage 63 is at the limit of the moving in the negative direction, down. These parameters a and b can to be measured experimentally. The algorithm governs the passage of the force Fc + a to the force Fc b in case of change in the direction of the user's request. The algorithm applies laws that use the linear velocity v of the carriage 63 and a coefficient kf, to know :
Fch0 = Fc + kf.v (10) Fc ¨b <Fch0 <Fc + a (11) Where Fch0 denotes the force imposed by default on the belt 64 by the motor 76, to know the value that is applied when the cursor 87 is placed on the 0 graduation.
in other words, if the cursor 37 is placed on the graduation 3000N for a program exercise plan to exercise this charge alternately in both directions, and that the cart 63 weighs 60kg, the electric motor will actually exert a force about 3600 N in climb and 2400 N downhill.

16 Thus, the higher the coefficient kf, the faster the machine responds to directional changes imposed by the user. Beyond a certain limit, a very high reactivity might require frequency filtering of the measurement speed, by example of low pass type of the first order.
Depending on the selected program, for example when a force of inertia artificial proportional to the acceleration and / or a viscous force proportional to the speed is applied by the engine, or when the program provides for reactions different in the concentric sense and in the eccentric sense, the force to apply computed may suffer discontinuity at the moment of the reversal of meaning, which is necessarily prejudicial to comfort of use of the machine.
According to one embodiment, the high-level controller 82 implements a algorithm to avoid these discontinuities. To do this, the controller 82 detects a change of direction by the passage of the speed signal in a hysteresis comparator schematically shown in FIG.
When starting the concentric phase, if the speed y> s, the controller triggers the transition from F2 to Fi. This variation is at a rate of variation constant, by example of the order of 200N / s.
Similarly, during the transition from the concentric phase to the eccentric phase, when the speed becomes negative and goes below a threshold y <-s, the controller 82 triggers the passage from Fi to F2. The threshold value s is chosen so as to ensure sufficient stability, know that the engine does not go from Fi to F2 untimely when the athlete decides to make a stop phase in his movement.
In FIG. 11, it should be noted that the curves of variation of the force in function speed between F1 and F2 values are not imposed by the system and depend in does the user's behavior, ie how does he vary the speed depending on the time, since the system imposes a force variation rate depending on the time.
In addition, the control program can prohibit the motor from realizing more than two consecutive changes if the position difference of the part mobile between the two changes do not exceed a certain limit, for example 10cm.
In other embodiments, the exercise program may also be include an elastic force contribution Fe defined as a function of a coefficient of proportionality k3 and according to the position z of the carriage 63:
Fe = k3 x (z ¨ z0) (12)

17 Where z0 is a parameterizable reference height and the z position is determined by the low-level controller 81.
So we understand that many exercise programs can be designed by combining the choice of additive contributions chosen in the group with a artificial inertia contribution proportional to the acceleration measured, a contribution viscous friction proportional to the measured speed, a contribution elastic proportional to the measured position, and a load contribution predetermined. According to one embodiment, the man-machine interface allows the user to adjust regardless of the parameters of each of these contributions, including coefficients k, k2 and k3.
Although the embodiments described above include motors rotatable, the control methods described above can be used with any Another type electric actuator. In particular, a linear motor can be used to generate a effort on the handling element.
Moreover, the calculation of the control signal can be carried out under different forms, in a unitary or distributed manner, by means of hardware components and / or software.
Usable hardware components are the specific integrated circuits ASIC, the networks FPGA programmable logic or microprocessors. Software components can be written in different programming languages, for example C, C ++, Java or VHDL.
This list is not exhaustive.
Although the invention has been described in connection with several modes of production particular, it is quite obvious that it is in no way includes all technical equivalents of the means described and their combinations if these enter in the context of the invention.
Use of the verb include, understand or include and its forms conjugates does not exclude the presence of other elements or other steps that those stated in a claim. The use of indefinite article one or one for an element or a step does not exclude, unless otherwise stated, the presence of a plurality of such elements or steps. Several means or modules can be represented by a single element equipment.
In the claims, any reference sign in parentheses can not to be interpreted as a limitation of the claim.

Claims (14)

1. Exercise device comprising a biasing member (6, 69) to be displaced by the force of a user, an electric actuator (1, 76) having a movable part (2), the element of solicitation (6, (39) being related to the moving part and the element of solicitation being able to move the moving part, a calculator (12, 80) capable of calculating a force to be exerted by the actuator electric and generate a control signal of the electric actuator according to the force to exercise calculated, so that the force exerted by the electric actuator (1) in signal response of control corresponds to the force to be exercised calculated and an acceleration sensor coupled to the movable portion (2) for measuring the acceleration of the moving part and for transmitting: the measured acceleration to the computer (12, 80) the electric actuator being able to exert a force on the element of solicitation (6, 69) by via the moving part in response to the control signal, wherein the calculator (12, 80) is adapted to calculate the force to be exerted in function of the acceleration measured by the acceleration sensor, characterized in that the device further comprises:
a memory of the computer in which is stored a coefficient of proportionality between the measured acceleration and an additive contribution inertia artificial, and a human-machine interface (86) allowing a user to adjust the coefficient of proportionality, the calculator being able to calculate the additive contribution of inertia artificial according to the measured acceleration and proportionality coefficient, the force at exercise calculated by the calculator according to the measured acceleration including the contribution additive of artificial inertia proportional to the measured acceleration obtained by the calculating as the result of a multiplication of the acceleration measured by the coefficient of proportionality stored in the memory, so that the force exerted by actuator electrical (1, 76) in response to the control signal includes the additive of artificial inertia proportional to the acceleration measured by the sensor acceleration and the proportionality factor stored in the memory. 2. Exercise device according to claim 1, characterized in that the calculating (12, 80) is able to vary the coefficient of proportionality in function of at least one parameter chosen from the position, velocity and acceleration of the part mobile, 3. Device exercise device according to claim 1 or 2, characterized in that the calculator (12, 80) is able to calculate the force to be exerted so that the force to exercise the electric actuator (1, 76) has an additive contribution of charge additional with a predetermined meaning. 4. Exercise device according to claim 3, characterized in that the calculating (12, 80) is able to calculate the force to be exerted so that the contribution additive of inertia artificial is oriented in the men-the meaning that the, contribution of meaning predetermined when the measured acceleration is in the opposite sense of the meaning contribution predetermined, Exercise device according to claim 4, characterized in that the calculating (12, 80) is capable of calculating the force to be exerted so as to cancel the additive contribution of artificial inertia when the measured acceleration is in the same direction that the contribution predetermined direction of the electric actuator (1, 76), Exercise device according to one of claims 1 to 5, characterized in that the connection between the biasing element (6, 69) and the movable part comprises a reducer speed to multiply the force of the motor. Exercise device according to one of Claims 1 to 6, characterized in that has a speed sensor capable of measuring the speed of the moving part (2) and that the calculator (12, 80) is adapted to generate the control signal so that strength exerted by the electric actuator (1, 76) has an additive contribution friction viscous substantially proportional to the speed measured by the sensor of speed. Exercise device according to one of claims 1 to 7, characterized in that the electric actuator (1, 76) is a linear motor or a rotary motor. 9. Device exercise device according to one of the claims 1 to 8, characterized in that the acceleration sensor comprises:
a position encoder (10, 84) coupled to the movable portion (2) for measuring the position of the moving part, the position encoder (10, 84) generating a position signal, branching elements (13, 14) adapted to derive the position signal for determine the acceleration of the moving part (2). 10. Disposition exercise device according to one of claims 1 to 9, characterized in that the exercise device is selected from the group consisting of rowers, the bikes indoor, lifting bars and guided load devices. 11. Device exercise device according to one of claims 1 to 10, characterized in that the calculator (12, 80) is able to calculate the force to be exerted so that the force to exercise the electric actuator (1, 76) has an additive contribution of charge additional arrangement having a predetermined direction, the human-machine interface (86) allowing a user to adjust the additive contribution of additional charge regardless of coefficient of proportionality. Exercise device according to claim 11, characterized in that the interface human-machine (86) allows a user to adjust the additive contribution charge additional to a value of zero. Exercise device according to one of claims 1 to 12, characterized in that the biasing element (69, 63) is movable in one direction vertical and that the calculator (12, 80) is able to calculate the force to be exerted in the absence of the force exerted by the user, so that the force to be exerted by the electric actuator (1, 76) has an additive load contribution by default offsetting a self weight of the element of solicitation (69, 63) without causing a spontaneous displacement of the element of solicitation (69, 63) in the absence of force exerted by the user. 14. A method of controlling an exercise device comprising:
measuring the acceleration of a moving part (2) of an electric actuator answer to force of a user exerted on a biasing element (6, 69) related to the moving part, calculate a force to be exerted by the electric actuator as a function of acceleration measured and generating a control signal for controlling the electric actuator (1,76) with the control signal so that the force exerted by the electric actuator (1, 76) in response to the control signal corresponds to the calculated force to be exerted, characterized by the steps of:
- Provide a human machine interface (86) allowing a user to settle a coefficient of proportionality between the measured acceleration and a additive contribution artificial inertia, - Store the coefficient of proportionality in a memory, - Multiply the acceleration measured by the proportionality coefficient to get the additive contribution of artificial inertia, and - Get the force to exercise calculated according to the measured acceleration including the additive contribution of artificial inertia proportional to acceleration measured, the force exerted by the electric actuator (1, 76) on the element of biasing (6, 6)) via the movable portion (2) in response at the signal of command has an additive contribution of artificial inertia proportional to measured acceleration.