Device for evaluating proprioceptive abilities of a subject, and associated method and computer program

Abstract

A device for evaluating proprioceptive abilities of a subject (8), the device comprising: - two articulated frames (21, 22); - a plurality of actuators (23, 24). Each articulated frame is rotatable around a first axis (X1, X2) and a second axis (Z1, Z2), and the device further comprises: - a sensor (45, 46) configured to detect positions of one of the articulated frames moving according to an original movement, the original movement being a rotation around at least one of the two axes, and to detect positions of one of the articulated frames moving according to a reproduced movement; and - a control unit (50), configured to command the actuators to move one of the articulated frames according to the original movement, and to compare the original movement and the reproduced movement.

Description

[0001] TITLE: Device for evaluating proprioceptive abilities of a subject, and associated method and computer program

[0002] The present invention concerns a device for evaluating proprioceptive abilities of a subject, a method for evaluating proprioceptive abilities of a subject and an associated computer program.

[0003] It is known to evaluate the proprioceptive abilities of a subject by qualitative experiments performed for example by a tester, such as a medical practitioner, on the subject. For example, a tester lifts one arm of the subject and asks him to reproduce the same movement, with the same arm, or with the other arm. The tester then qualitatively determines if the subject correctly reproduced the movement.

[0004] However, this process could lack precision, and can only be performed if the subject is able to move his arms by himself. In addition to this, the range of movements that can be performed is fairly limited, since the tester needs to keep track of the movement he / she imposes on one of the arms of the patient, and compare it to the movement reproduced by the patient using the same arm, or the other arm.

[0005] An aim of the invention is therefore to provide precise analysis of movements performed by the subject with his arms, and to make such tests easier to perform.

[0006] To this end the invention relates to a device for evaluating proprioceptive abilities of a subject, the device comprising:

[0007] - a first and second articulated frames, each first and second frame being configured to support an arm of the subject;

[0008] - a first and second actuators, mechanically connected to one of the first and second frames.

[0009] According to the invention:

[0010] - each first and second articulated frame is rotatable around a first axis and a second axis, the first and second axes intersecting each other;

[0011] - each first and second articulated frame comprises a plate configured to support one of the forearm of the subject, an auxiliary plate configured to support part of an upper arm of the subject and located at one end of the plate and a handle located on an end of its plate, away from the corresponding auxiliary plate along an axis, perpendicular to first and second axes, for the subject to hold with his hand, when the arms of the subject each rest on one of the first and second articulated frames;- the first actuator is configured to move the firstarticulated frame around the two axes and the second actuator is configured to move the second articulated frame around the two axes;

[0012] and the device further comprises:

[0013] - at least one sensor configured to detect successive positions of one of the first and second articulated frames moving according to a predetermined movement, called original movement, the original movement being a rotation around at least one of the two axes, and further configured to detect successive positions of one of the first and second articulated frames moving to reproduce the original movement, called reproduced movement; and

[0014] - a control unit, connected to the sensors and the first and second actuators, and configured to command the first and second actuators to move one of the first and second articulated frames according to the original movement, and to compare the original movement and the reproduced movement.

[0015] Thanks to the invention, both the original and the reproduced movements of the arms of the subject are precisely measured. It is therefore possible to quantitatively evaluate the subject’s proprioceptive abilities, with improved accuracy. Since it is the device that moves one of the frame, and the arm supported by the frame, according to the predetermined movement, it is possible to reproduce accurately over time the same movements, for example to detect and measure improvement or worsening of the proprioceptive abilities of the subject. Furthermore, the use of the frame allows to move the subject’s arms according to more complex movements than the tester would be able to accurately compare on his own, for example a three-dimensional movement according to both the first and secondary axes. This makes testing the proprioceptive abilities easier for the tester, and also improves the quality of the test, as more varied movements can be performed. The use of the frame also allows testing proprioceptive abilities of subjects that cannot move their arms on their own, without the tester having to move the arms of the subject, thus making the testing easier for the tester and available to a wider range of people.

[0016] According to other advantageous aspects of the invention, the device comprises one or several of the following features, taken independently or according to any technically feasible combinations:

[0017] - the sensors are camera sensors and each first and second articulated frame comprises an optical tracker to detect successive positions of the first and second articulated frames moving according to the original movement and the reproduced movement;

[0018] - the first and second axes are perpendicular to each other;- each first and second articulated frame comprises a handle, for the subject to hold with his hand, when the arms of the subject each rest on one of the articulated frames;

[0019] - the first and second articulated frame moving according to the reproduced movement is the same articulated frame that moves according to the original movement;

[0020] - the first and second articulated frame moving according to the reproduced movement is different from the first and second articulated frame moving according to the original movement;

[0021] - the control unit is configured to command the actuators to move one of the first and second articulated frames according to the reproduced movement, and to stop moving the first and second articulated frame following a command by the subject;

[0022] - each motor of the plurality of actuators is mechanically connected to one of the first and second articulated frames by a wire and pulley system;

[0023] - the plurality of actuators comprises three motors, each motor being configured to move one of the articulated frame via the wire and pulley system, and three other motors, each configured to move the other articulated frame via the wire and pulley system;

[0024] - the first actuator comprises a first motor mechanically connected to the first articulated frame by a first wire and pulley system and the second actuator comprises a second motor mechanically connected to the second articulated frames by a second wire and pulley system;- each articulated frame comprises a plate and an auxiliary plate, located at one end of the plate;

[0025] - for each first and second articulated frame, the auxiliary plate forms an angle with the plate belonging to the same articulated frame;

[0026] For example, the device comprises comprising three first actuators, each comprising one first motor, each first motor being configured to move the first articulated frame via the first wire and pulley system, and comprising three second actuators, each comprising one second motor, each second motor being configured to move the second articulated frame via the second wire and pulley system.

[0027] Advantageously, the first motors are each mechanically connected to the first frame by a first wire and pulley system and the second motors are each mechanically connected to the second frame by a second wire and pulley system, the wires that are part of the first wire and pulley systems are attached to the first handle and the wires that are part of the second wire and pulley systems are attached to the second handle.

[0028] Advantageously, the actuators are axially offset from the plate and the auxiliary plate of the corresponding articulated frame, i.e. the actuators are not located on the articulated frame.The invention also relates to a method for evaluating proprioceptive abilities of a subject, using the device previously described, the method comprising at least the following steps:

[0029] - commanding, by the control unit, the actuators to move one of the articulated frames according to the original movement;

[0030] - detecting, by the at least one sensor, the successive positions of the frame moving according to the original movement;

[0031] - moving one of the articulated frames, to reproduce the original movement, the movement performed being the reproduced movement;

[0032] - detecting, by the at least one sensor, the successive position of the articulated frame moving according to the reproduced movement; and

[0033] - comparing, by the control unit, the original movement and the reproduced movement as detected by the at least one sensor.

[0034] According to other advantageous aspects of the invention, the method comprises one or several of the following features, taken independently or according to any technically feasible combinations:

[0035] - the original movement is a rotation around the two axes; and

[0036] - moving one of the articulated frames to reproduce the original movement is performed by the subject, or by the actuators.

[0037] The invention further relates to a computer program comprising software instructions that, when executed by a computer, implement a method for evaluating proprioceptive abilities of a subject, using the device as described before, the method comprising at least the following steps:

[0038] - commanding, by the control unit, the first and second actuators to move one of the first and second articulated frames according to the original movement; - detecting, by the at least one sensor, the successive positions of the frame moving according to the original movement;

[0039] - moving one of the first and second articulated frames, to reproduce the original movement, the movement performed being the reproduced movement;

[0040] - detecting, by the at least one sensor, the successive position of the articulated frame moving according to the reproduced movement; and - comparing, by the control unit, the original movement and the reproduced movement as detected by the at least one sensor, wherein the original movement is a rotation around the two axes and wherein moving one of the firstand second articulated frames to reproduce the original movement is performed by the subject, or by the actuators.

[0041] The invention will be better understood upon reading the following description, given solely by way of a non-limiting example, and made with reference to the drawings in which:

[0042] [Fig. 1] Figure 1 is a perspective schematic view of a device according to the invention;

[0043] [Fig. 2] Figure 2 is a representation of the device of figure 1 in use, when an original movement is according to the first axis;

[0044] [Fig. 3] Figure 3 is a representation of the device of figures 1 and 2 in use, when the original movement is according to the second axis, and

[0045] [Fig. 4] Figure 4 is a block diagram of a method according to the invention.

[0046] In the following description, “equal to” means equal to plus or minus 5%.

[0047] Figure 1 represents a device 5 for evaluating proprioceptive abilities of a subject 8, the subject 8 being represented on figure 2. The subject 8 will be referred to as he / him, but this should not be considered a limitation on the gender of the subject. The subject 8 may be an adult or a child. In particular, the device 5 evaluates the proprioceptive abilities of an arm and / or forearm of the subject 8. The device 5 advantageously comprises a support 10, including support frames 12 and 13, visible on figure 1. Support frames 12 and 13 extend parallel to a plane defined by two axes X and Y. The axes X and Y are perpendicular to each other and advantageously parallel to a flat ground surface; in other words, the axes X and Y are horizontal. Therefore, the support frame 12 is advantageously horizontal.

[0048] The support 10 advantageously comprises vertical bars, which are not represented. The vertical bars extend along an axis Z, perpendicular to the axes X and Y, to rigidly connect the support frame 12 with the support frame 13.

[0049] The device 5 further comprises two articulated frames 21 and 22, and a plurality of actuators 23 and 24, mechanically connected to the articulated frames 21 and 22. In particular, the actuators 23 are connected to the articulated frame 21 and the actuators 24 are connected to the articulated frame 22.

[0050] Each articulated frame 21 or 22 is configured to support an arm 28 of the subject 8, as represented for frame 21 on figures 2 and 3. To this end the articulated frames 21 and 22 respectively comprise a plate 31 or 32, each plate 31 and 32 being configured to support one of the arms 28 of the subject 8. In particular, the plates 31 and 32 are each configured to support one of the forearm of the subject 8. Plate 31 advantageously extends along an axis Y1, linked to the articulated frame 21. The axis Y1 is parallel to the axis Y when the device 5 is not in use. In other words, when the device 5 is not in use, the plate 31 is horizontal. Similarly, plate 32 advantageously extends along an axis Y2, linked to thearticulated frame 22. The axis Y2 is parallel to the axis Y when the device 5 is not in use. In other words, when the device 5 is not in use, the plate 32 is horizontal.

[0051] The articulated frames 21 and 22 advantageously further comprise auxiliary plates 33 and 34 respectively. The auxiliary plates 33 and 34 are each located at one end of the plates 31 and 32. For example, the auxiliary plate 33 is located at one end of the plate 31, along the axis Y1 , and the auxiliary plate 34 is located at one end of the plate 32, along the axis Y2. The auxiliary plates 33, 34 are advantageously configured to support part of an upper arm of the subject 8, or an elbow of the subject 8.

[0052] Advantageously, the auxiliary plates 33 and 34 do not extend parallel to the axes Y1 and Y2. In particular, the auxiliary plates 33 and 34 form an angle A1, A2 with respectively the plates 31 and 32. The angles A1 , A2 are equal to or greater than 90°. The angle A1 is formed in a plane defined by axis Y1 and an axis Z1, advantageously perpendicular to axis Y1. Advantageously, when the device 5 is not in use, the axis Z1 is vertical, in other words, parallel to the axis Z. The angle A2 is formed in a plane defined by axis Y2 and an axis Z2, advantageously perpendicular to axis Y2. Advantageously, when the device 5 is not in use, the axis Z2 is vertical, in other words, parallel to axis Z.

[0053] Advantageously, the angles A1 and A2 are equal to each other.

[0054] Each articulated frame 21 or 22 advantageously comprises a handle 35, 36, located on an end of its plate 31 or 32, away from the corresponding auxiliary plate 33 or 34 along the axis Y1 or Y2, respectively. The subject can hold the handles 35, 36 with his hands, when his arms 28 each rest on one of the articulated frames 21, 22.

[0055] Advantageously, a distance between frames 21 and 22 along the axis X1 or X2 is adjustable, to adapt the distance between the frames 21 and 22 to the preferences and / or size, in particular the shoulder size, of the subject 8.

[0056] Advantageously, a distance between plate 31 and handle 35, and between plate 31 and auxiliary plate 33 along the axis Y1 is adjustable. In particular, this allows subjects of different arm lengths to be supported comfortably by the frame 21. Similarly, a distance between plate 32 and handle 36, and between plate 32 and auxiliary plate 34 along the axis Y1 is also adjustable.

[0057] Advantageously, the plates 31, 32, the handles 35, 36 the auxiliary plate 33, 34 are mobile along axes Z1 and Z2, respectively, to adjust them according to preferences and / or size of the subject 8.

[0058] Advantageously, the angles A1 and A2 are also adjustable, according to preferences and / or size of the subject 8.

[0059] The frame 21 is rotatable around an axis X1, advantageously perpendicular to axis Y1, and around the axis Z1. Axes X1 and Z1 intersect each other, and advantageously, areperpendicular to each other. When the device 5 is not in use, the axis X1 is advantageously horizontal.

[0060] Similarly, frame 22 is rotatable around an axis X2, advantageously perpendicular to axis Y2 and around the axis Z2. Axes X2 and Z2 intersect each other, and advantageously, are perpendicular to each other. When the device 5 is not in use, the axis X2 is advantageously horizontal.

[0061] The actuators 23 and 24 advantageously comprise motors 37, 38, which are advantageously electrical motors. The actuators 23 and 24 advantageously further comprise a wire and pulley system 41 , 42. In the example of the figures, each motor 37, 38 of the plurality of actuators 23, 24 is mechanically connected to one of the articulated frames 21, 22 by one of the wire and pulley systems 41, 42. In particular, the motors 37 are each mechanically connected to the frame 21 by a wire and pulley system 41 and the motors 38 are each mechanically connected to the frame 22 by a wire and pulley system 42. In the example of the figures, the wires that are part of the wire and pulley systems 41 are attached to the handle 35 and the wires that are part of the wire and pulley systems 42 are attached to the handle 36.

[0062] Advantageously, the device 5 comprises three actuators 23 and three actuators 24, each comprising one motor. The actuators 23 each comprise one motor 37 and the actuators 24 each comprise one motor 38. All three actuators 23 and all three actuators 24 are configured to rotate the frame 21 and the frame 22 respectively around axes X1 and Z1 and around axes X2 and Z2. In a preferred variant, one of the actuators 23 and one of the actuators 24 are configured respectively to rotate the frame 21 around axis X1 and to rotate the frame 22 around axis X2 and the other two actuators 23 and two actuators 24 are advantageously configured respectively to rotate the frame 21 around axis Z1 and the frame 22 around axis Z2.

[0063] In a variant that is not represented, the actuators 23 and 24 are of a different type, for example comprise pistons or hydraulic or pneumatic circuits.

[0064] The device 5 further comprises two sensors 45, 46, which are camera sensors. The sensors 45, 46, are configured to detect successive positions of the frames 21, 22 when the frames 21 and 22 move.

[0065] Advantageously, the sensor 45 is configured to detect successive positions of the frame 21, and the sensor 46 is configured to detect successive positions of the frame 22.

[0066] Advantageously, the position of the frames 21 and 22 are detected by the sensors 45 and 46 by tracking optical trackers 47, 48 respectively comprised in the articulated frames 21 , 22. For example, the optical tracker 47 is located on the handle 35, away from the plate31 along axis Y1, and the optical tracker 48 is located on the handle 36, away from the plate 32 along axis Y2.

[0067] The optical trackers 47, 48 may be passive, in that they are not electrically powered, and are for example fiducial markers, reflecting markers or colored markers. In variant, the optical trackers are active, in other words are configured to emit a signal, such as light, when electrically powered, and are for example LEDs or laser diodes.

[0068] In variant, the sensors 45, 46 are configured to detect the position of the frames 21, 22 without optical trackers, for example by object detection and recognition methods.

[0069] In variant, not represented, the device 5 comprises one sensor, or more than two sensors. The sensors may be of a type different from camera sensors, for example radar, lidar or ultrasound sensors. The optical trackers 47, 48 may be passive or active, and for example, in the case of ultrasound sensors, may be configured to emit ultrasound waves to be detected by the sensors 47, 48.

[0070] Advantageously, the precision of the sensors 45, 46 is equal to, or smaller than 0.1°. In other words, any rotation around axes X1 or Z1, or around axes X2 or Z2 that has an angle greater than 0.1° will be considered a movement. Advantageously, the precision is equal to 0.01°.

[0071] The device 5 further comprises a control unit 50, connected to the sensors 45, 46, and to the actuators 23 and 24. For the sake of simplicity, the connection between the control unit 50 and the actuators 23 and 24 is not shown on figures 1 and 2. The control unit 50 is for example implemented in the form of a programmable logic component, such as an FPGA, or Field Programmable Gate Array, or an integrated circuit, such as an ASIC, or Application Specific Integrated Circuit.

[0072] In variant, the control unit 50 is implemented as a computer program, also known as a computer program product, and is also suitable for recording on a computer-readable medium, not shown. The computer-readable medium is, for example, a medium capable of storing electronic instructions and of being coupled to a bus of a computer system. By way of example, the readable medium is an optical disk, a magneto-optical disk, a ROM memory, a RAM memory, any type of non-volatile memory (e.g. FLASH or NVRAM) or a magnetic card. A computer program containing software instructions is stored on the readable medium.

[0073] The control unit 50 is configured to command the actuators 23, 24, to move the frames 21, 22.

[0074] Advantageously, the control unit 50 is also configured to command the actuators to move the frame with specific angular velocity.The control unit 50 is further configured to receive from the sensors 45 and 46, signals representative of the successive positions of the frames 21 and 22 and to compare these successive positions. The mode of operation of the control unit 50 will be explained in further detail here below.

[0075] Advantageously, the control unit 50 is connected to a terminal 52, via a wired or a wireless connection. The terminal 52 is for example a personal electronic device, such as a computer or a smartphone, and is configured for example to display messages, results of calculations received from the control unit 50. In some examples, a tester, such as a medical practitioner, may control the device 5 via the terminal 52, which then acts as a humanmachine interface.

[0076] An operation of the device 5 is now described.

[0077] The subject 8 places one of his arms 28 on articulated frame 21. Advantageously, the subject places one of his arms on frame 21 and the other on frame 22.

[0078] The subject 8 advantageously holds on to the handles 35 and 36 with his hands while his arms 28 are supported by the articulated frames 21 and 22, as shown only for the left arm 28 of the subject 8 on figures 2 and 3.

[0079] In some examples, the arms 28 of the subject are secured to the frames 21 and 22, for example by straps, to prevent slipping and / or falling of the arms 28 from the frames 21 and 22.

[0080] The tester, via the terminal 52, or the subject 8 via his own muscular force, commands the device 5, to perform a method for evaluating proprioceptive abilities of the subject 8. The method is performed by the device 5. The method is described with reference to figure 4. Before the method is performed, the frames 21, 22 are in an initial position, which is the position of the frames 21, 22 when the device 5 is not in use.

[0081] The control unit 50 commands the actuators 23 or 24 to move one of the frames 21 , 22 according to a predetermined movement, called original movement, at step S102. The original movement is performed only by one of the articulated frames 21 or 22, while one arm 28 of the subject 8 is supported by the frame 21 or 22. Advantageously, the actuators 23 and 24 respectively move the frames 21, 22 via the motors 37 and wire and pulley systems 41, and via the motors 38 and the wire and pulley systems 42.

[0082] The next paragraph will describe the case where articulated frame 21 moves according to the original movement. This description is also valid for articulated frame 22, replacing the axes X1 and Z1 by axes X2 and Z2, sensor 45 by sensor 46, and optical tracker 47 by optical tracker 48.

[0083] The original movement is a rotation around axis X1 as visible in figure 2, or around axis Z1, as visible in figure 3, or, advantageously, a rotation around both axes X1 and Z1.In some examples, the tester specifies what is the original movement, for example the type of rotation, and the amplitude of the movement. The amplitude of the movement is for example specifically chosen by the tester. Advantageously, a rotation of the frame 21 around the axis Z1 has an angle between 45° and +45°, advantageously between -30° and +30° from the position of the frame 21 when it is not in use. Advantageously, a rotation of the frame 21 around the axis X1 has an angle equal to or smaller than 135° from the position of the frame 21 when it is not in use.

[0084] In variant, a library of predefined original movements is stored in the control unit 50 and the tester chooses one. In another variant, a library of predefined original movements is stored in the control unit 50 and one is selected randomly, or according to instructions input by the tester, by the control unit 50.

[0085] Once the original movement is selected, the control unit 50 commands the actuators 23 to move the frame 21 according to the original movement. The arm 28 that rests on the frame 21 moves with the frame 21 according to the original movement.

[0086] Advantageously, the control unit 50 commands the actuators 23 to move the frame 21 according to a predetermined angular velocity, for example a value between 57s to 207s, for example 107s. In other examples, the angular velocity is variable during the original movement.

[0087] At step S104, the sensor 45 detects the successive positions of the frame 21 moving according to the original movement. In particular, the sensor 45 detects the movement of the optical tracker 47 and determines the successive positions of the frame 21 based on the position of the optical tracker 47. The successive positions are sent to the control unit 50.

[0088] Once the frame 21 has moved according to the original movement, the frame 21 can stay in a final position of the original movement, or the control unit 50 can command the actuators 23 to move the frame 21 back in the initial position.

[0089] For example, in the case of an ipsi-lateral test, the subject’s 8 ability to repeat a movement imposed on one arm 28 with the same arm is tested. In this case, once the frame 21 has moved according to the original movement, the control unit 50 can command the actuators 23 to move the frame 21 back in the initial position.

[0090] In the case of a contra-lateral test, the subject’s 8 ability to repeat a movement imposed to one arm 28 with the other arm is tested. In this case the frame 21 can either stay in the final position of the original movement or can be commanded to move back in the initial position.One of the frames 21, 22 is then moved to reproduce the original movement at step S106. The movement performed by the frame 21 or 22 at step S106 is called a reproduced movement.

[0091] In the example of an ipsi-lateral test, the frame 21 is moved to reproduce the original movement at step S106. In the example of a contra-lateral test, the frame 22 is moved to reproduce the original movement at step S106. In other words, in a contra-lateral test, the frame that moves according to the reproduced movement is different from the frame that moves according to the original movement.

[0092] In an ipsi-lateral test, the reproduced movement and the original movement are performed by the same arm 28, and can be superposed to each other. In a contra-lateral test, the reproduced movement and the original movement are performed by different arms, and the reproduced movement is symmetric to the original movement along a sagittal plane of the subject 8. The sagittal plane of the subject 8 is parallel to the plane formed by the axes Y and Z. The original and reproduced movement therefore cannot be superposed to each other.

[0093] Both in an ipsi-lateral test and a contra-lateral test, the frame 21 or 22 that is moved during step S106 is moved by the subject 8 himself, or, in alternative, moved by the actuators 23 or 24.

[0094] In the first case, the subject 8 moves the frame 21 or 22 to reproduce the original movement to the best of his ability.

[0095] In the second case, the control unit 50 commands the actuators 23 or 24 to move the frame 21 or 22 to reproduce the original movement. In particular, the frame 21 or 22 moves along a trajectory identical to the one followed during the original movement, and stops following a command by the subject 8. Such a command is for example pressing on a pedal, a voice command, or a signal to the tester, who then stops the movement of the frame 21 or 22. The control unit 50 commands the actuators 23 or 24 to move the frame 21 or 22 at an angular velocity that is identical to the angular velocity of the original movement, or in variant, a different, or variable angular velocity.

[0096] The sensor 45, respectively 46, detects the successive positions of the frame 21, respectively 22, moving according to the reproduced movement at step S108. In particular, the sensor 45, 46 detects the movement of the optical tracker 47 or 48 and determines the successive positions of the frame 21 or 22 based on the position of the optical tracker 47, 48. The successive positions are sent to the control unit 50.

[0097] The control unit then compares the successive positions detected while the frame 21 was moving according to the original movement, and the successive positions detected while the frame 21 or 22 was moving according to the reproduced movement, at step S110.In other words, the control unit 50 compares the original movement and the reproduced movement as detected by the sensor 45 or 46. In particular, the control unit 50 determines if there are discrepancies in an angle of the rotation performed during the reproduced movement compared to the original movement.

[0098] The control unit 50 advantageously sends a message for display on the terminal 52 at an emission step S112. The message is for example a graph showing the original movement and the reproduced movement, discrepancies between the two if there are any, such as a wrong trajectory, different amplitudes, reflecting for example that the subject stopped too early or too late when performing the reproduced movement.

[0099] The data displayed is for example interpreted by the tester to determine if the subject 8 has impaired proprioceptive abilities and to what degree. For example, by comparing different types of movements, such as rotations around axes X1, Z1 and a combination of both, and by precisely detecting the successive positions, it is possible to accurately determine if the impairment to proprioceptive abilities of the subject 8 is heavy or light, for example based on a percentage of the reproduced trajectory which accurately reproduces the original trajectory. It is also possible to monitor proprioceptive abilities of the subject 8 over time, for example by storing the messages emitted at emission step S112 and comparing them with later messages.

[0100] This method may be repeated, for example during a series of test evaluating proprioceptive abilities of the subject 8, with movement along different axes, with varying amplitudes or both.

[0101] The device 5 can be used by testers such as medical practitioners, who can use the messages emitted at step S112 to assess the proprioceptive abilities of one or several subjects. In this case, it is necessary that the medical practitioner interprets the message displayed on the terminal to establish such an assessment. The device 5 can also be used in other settings, such as in sports centres, to improve proprioceptive abilities of athletes.

[0102] Any feature described for one embodiment or variant may be implemented for the other embodiments and variants described above, insofar as technically feasible.

Claims

CLAIMS1. A device (5) for evaluating proprioceptive abilities of a subject (8), the device (5) comprising:- A first and a second articulated frames (21 , 22), each first and second frame (21 , 22) being configured to support an arm (28) of the subject (8);- a first and second actuators (23, 24), each mechanically connected to one of the first and second articulated frames (21, 22);characterized in that:- each first and second articulated frame (21, 22) is rotatable around a first axis (X1 , X2) and a second axis (Z1 , Z2), the first and second axes (X1 , Z1 , X2, Z2) intersecting each other;- each first and second articulated frame (21, 22) comprises a plate (31, 32) configured to support one of the forearm of the subject (8), an auxiliary plate (33, 34) configured to support part of an upper arm of the subject (8) and located at one end of the plate (31, 32) and a handle (35, 36) located on an end of its plate (31 , 32), away from the corresponding auxiliary plate (33, 34) along an axis (Y1 , Y2), perpendicular to first and second axes (X1, Z1, X2, Z2), for the subject (8) to hold with his hand, when the arms (28) of the subject each rest on one of the first and second articulated frames (21, 22);the first actuator (23) is configured to move the first articulated frame (21) around the two axes (X1, Z1) and the second actuator (24) is configured to move the second articulated frame (22) around the two axes (X2, Z2); and in that the device (5) further comprises:- at least one sensor (45, 46) configured to detect successive positions of one of the first and second articulated frames (21, 22) moving according to a predetermined movement, called original movement, the original movement being a rotation around at least one of the two axes (X1 , Z1 , X2, Z2), and further configured to detect successive positions of one of the first and second articulated frames (21, 22) moving to reproduce the original movement, called reproduced movement; and- a control unit (50), connected to the sensors (45, 46) and the first and second actuators (23, 24), and configured to command the first and second actuators (23, 24) to move one of the first and second articulated frames (21 , 22) according to the original movement, and to compare the original movement and the reproduced movement.

2. Device (5) according to claim 1, wherein the sensors (45, 46) are camera sensors and each first and second articulated frame (21 , 22) comprises an optical tracker (47, 48) to detect successive positions of the first and second articulated frames (21 , 22) moving according to the original movement and the reproduced movement.

3. Device (5) according to any one of claims 1 and 2, wherein the first and second axes (X1, X2, Z1, Z2) are perpendicular to each other.

4. Device (5) according to any one of claims 1 to 3, wherein the first and second articulated frame (21, 22) moving according to the reproduced movement is the same first and second articulated frame (21 , 22) that moves according to the original movement.

5. Device (5) according to any one of claims 1 to 3, wherein the first and second articulated frame (21 , 22) moving according to the reproduced movement is different from the first and second articulated frame (21 , 22) moving according to the original movement.

6. Device (5) according to any one of claims 1 to 5, wherein the control unit (50) is configured to command the first and second actuators (23, 24) to move one of the first and second articulated frames (21 , 22) according to the reproduced movement, and to stop moving the first and second articulated frame (21, 22) following a command by the subject.

7. Device (5) according to any one of claims 1 to 6, wherein the first actuator (23) comprise a first motor (37) mechanically connected to the first articulated frame (21) by a first wire and pulley system (41) and the second actuator (24) comprises a second motor (38) mechanically connected to the second articulated frames (22) by a second wire and pulley system (42).

8. Device (5) according to claim 7, comprising three first actuators (23), each comprising one first motor (37), each first motor being configured to move the first articulated frame (21) via the first wire and pulley system (41), and comprising three second actuators (24), each comprising one second motor (38), each second motor (38) being configured to move the second articulated frame (22) via the second wire and pulley system (42).

159. Device (5) according to claim 8, wherein, the first motors (37) are each mechanically connected to the first frame (21) by the first wire and pulley system (41) and the second motors (38) are each mechanically connected to the second frame (22) by the second wire and pulley system (42), the wires that are part of the first wire and pulley systems (41) are attached to the first handle (35) and the wires that are part of the second wire and pulley systems (42) are attached to the second handle (36).

10. Device (5) according to any of the preceding claims, wherein for each first and second articulated frame (21, 22), the auxiliary plate (33, 34) forms an angle (A1, A2) with the plate (31 , 32) belonging to the same articulated frame (21 , 22).

11. Device (5) according to any of the preceding claims, wherein the first and second actuators (23, 24) are axially offset from the plate (31, 32) and the auxiliary plate (33, 34) of the corresponding articulated frame (21, 22).

12. Computer program comprising software instructions that, when executed by a computer, implement a method for evaluating proprioceptive abilities of a subject (8), using the device (5) of any one of claims 1 to 11 , the method comprising at least the following steps:- commanding (S102), by the control unit (50), one of the first and second actuators (23, 24) to move one of the first and second articulated frames (21 , 22) according to the original movement;- detecting (S104), by the at least one sensor (45, 46), the successive positions of the frame (21 , 22) moving according to the original movement;- moving one of the first and second articulated frames (21, 22), to reproduce the original movement (S106), the movement performed being the reproduced movement;- detecting (S108), by the at least one sensor (45, 46), the successive position of the first and second articulated frame (21, 22) moving according to the reproduced movement; and - comparing (S110), by the control unit (50), the original movement and the reproduced movement as detected by the at least one sensor (45, 46), wherein the original movement is a rotation around the two axes (X1, Z1, X2, Z2) and wherein moving one of the first and second articulated frames (21, 22) to16reproduce the original movement (S106) is performed by the subject (8), or by one of the first and second actuators (23, 24).

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