End position estimation device, method and exoskeleton binding device

Abstract

The embodiments of the present disclosure provide an end position estimation device, method and exoskeleton binding equipment, wherein the end position estimation device includes a Bowden cable, a plurality of optical waveguide sensors evenly spaced along the circumference of the Bowden cable, and a processing unit electrically connected to the plurality of optical waveguide sensors; each of the optical waveguide sensors is used to obtain an actual voltage signal corresponding to the bending of the Bowden cable; the processing unit is used to calculate the actual bending angle based on each of the actual voltage signals and a preset voltage-bending angle relationship model, so as to determine the end position of the Bowden cable according to the actual bending angle. In the present disclosure, the end position estimation device adopts the technology of integrating multiple optical waveguide sensors, which can detect the actual bending angle of the Bowden cable in space, and can accurately estimate the end position of the Bowden cable in space based on the obtained actual bending angle.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the technical field of motion assisting devices, and specifically relate to an end position estimation device, method and exoskeleton binding device. Background Art

[0002] Exoskeleton devices have been widely used in the fields of rehabilitation medicine and assistive devices. They help patients recover their motor functions or enhance their working ability by assisting human movement. However, most existing flexible exoskeleton devices use Bowden cables and steel cables for transmission. During the operation of the exoskeleton, when the user is changed or the body posture changes or when there is external interference, the joint position will shift, so that the exoskeleton cannot accurately reach the ideal position, resulting in the exoskeleton being unable to achieve the expected goals and functions during the movement.

[0003] Traditionally, the end position is often detected and estimated through ultrasound, lidar or gyroscopes, but they are often extremely expensive and susceptible to external interference. In addition, the above detection devices occupy a large volume, are not portable, and have cumbersome processing methods, which greatly increases the difficulty of subsequent maintenance and is difficult to apply to wearable exoskeletons composed of multiple joints.

[0004] Therefore, how to solve the above problems has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art, and provide an end position estimation device, method and exoskeleton binding equipment.

[0006] According to a first aspect of an embodiment of the present disclosure, there is provided an end position estimation device, the end position estimation device comprising a Bowden cable, a plurality of optical waveguide sensors evenly spaced along a circumference of the Bowden cable, and a processing unit electrically connected to the plurality of optical waveguide sensors;

[0007] Each of the optical waveguide sensors is used to obtain an actual voltage signal corresponding to the bending of the Bowden cable;

[0008] The processing unit is used to calculate the actual bending angle based on each of the actual voltage signals and a preset voltage-bending angle relationship model, so as to determine the end position of the Bowden cable according to the actual bending angle.

[0009] Optionally, the plurality of optical waveguide sensors include a first optical waveguide sensor, a second optical waveguide sensor and a third optical waveguide sensor;

[0010] The relationship between the actual voltage signal and the bending angle corresponding to the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor respectively satisfies the conditional formula:

[0011] ,

[0012] ,

[0013] ,

[0014] Wherein, θ˙ is the actual bending angle of the center of the Bowden cable, θ¨ is the actual bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when they are synchronously bent with the Bowden cable, and Y L1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor, wherein it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0015] Optionally, along the axial direction of the Bowden cable, the plurality of optical waveguide sensors are bonded around the outer circumference of the Bowden cable by means of EVA resin.

[0016] Optionally, the end position estimation device further includes a light source assembly and a light intensity receiving device; the first end of the Bowden cable is connected to the light source assembly, and the second end is connected to the light intensity receiving device;

[0017] The first ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light source assembly, the second ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light intensity receiving device, and the light intensity receiving device is electrically connected to the processing unit.

[0018] Optionally, the Bowden cable and the multiple optical waveguides are fixedly connected to the light source assembly and the light intensity receiving device respectively through UV glue.

[0019] Optionally, the light source assembly includes a light source fixing device and a red LED light source with a 15-degree lens disposed in the light source fixing device, wherein the material of the light source fixing device includes ABS mixed with glass fiber.

[0020] According to a second aspect of an embodiment of the present disclosure, there is provided a method for estimating a terminal position. The method is implemented according to the above-mentioned terminal position estimation device, and includes:

[0021] Acquire actual voltage signals corresponding to a plurality of optical waveguide sensors evenly spaced and arranged in a circumferential direction of the Bowden cable when the Bowden cable is bent;

[0022] Based on each of the actual voltage signals and a preset voltage-bending angle relationship model, an actual bending angle is calculated;

[0023] The end position of the Bowden cable is determined according to the actual bending angle.

[0024] Optionally, the plurality of optical waveguide sensors include a first optical waveguide sensor, a second optical waveguide sensor and a third optical waveguide sensor;

[0025] The relationships between the actual voltage signals and the bending angles corresponding to the first optical waveguide sensor, the second optical waveguide sensor, and the third optical waveguide sensor respectively satisfy the conditional formula:

[0026] ,

[0027] ,

[0028] ,

[0029] Wherein, θ˙ is the central bending angle of the Bowden cable, θ¨ is the bending angle when the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor are synchronously bent with the Bowden cable, and Y L1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor, wherein it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0030] According to a third aspect of the embodiments of the present disclosure, there is provided an exoskeleton binding device, wherein the binding device comprises the above-mentioned terminal position estimation device.

[0031] The beneficial effects of the embodiments of the present disclosure include:

[0032] In the present disclosure, the end position estimation device adopts the technology of integrating multiple optical waveguide sensors, which can detect the bending angle of the Bowden cable in space, and can accurately estimate the end position of the Bowden cable in space based on the actual bending angle obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of an end position estimation device according to an embodiment of the present disclosure;

[0034] Figure 2 The present invention discloses the relationship between the bending angle and the voltage value measured by a single optical waveguide sensor concentric with the Bowden wire in the xy plane and the yz plane under the standard Cartesian position system, and the error bar diagram and the corresponding fitting curve;

[0035] Figure 3The present invention discloses the relationship between the bending angle and the voltage value measured by three optical waveguide sensors in a circular array attached to the Bowden cable on the xz plane in a standard Cartesian coordinate system and an error bar graph;

[0036] Figure 4 for Figure 3 A fitting diagram of the changes in the voltage values ​​corresponding to the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor;

[0037] Figure 5 for Figure 4 a difference between the voltage values ​​of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor;

[0038] Figure 6 The figure is a flowchart of a method for estimating an end position according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, the present disclosure is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0040] The following is a further detailed description of the implementation methods of the present application in conjunction with the accompanying drawings and examples. The detailed descriptions and drawings of the following examples are used to illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments. In the description of the present application, it should be noted that, unless otherwise specified, the meaning of "multiple" is more than two; the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inside", "outside", etc. is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the error tolerance range. "Parallel" is not parallel in the strict sense, but within the error tolerance range.

[0041] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0042] like Figure 1As shown, an end position estimation device includes a Bowden cable, a plurality of optical waveguide sensors evenly spaced along the circumference of the Bowden cable, and a processing unit electrically connected to the plurality of optical waveguide sensors.

[0043] Each optical waveguide sensor is used to obtain an actual voltage signal corresponding to the bending of the Bowden cable. The processing unit is used to calculate the actual bending angle based on each actual voltage signal and a preset voltage-bending angle relationship model, so as to determine the end position of the Bowden cable according to the actual bending angle.

[0044] In the present disclosure, the end position estimation device adopts the technology of integrating multiple optical waveguide sensors, which can detect the actual bending angle of the Bowden cable in space, and can accurately estimate the end position of the Bowden cable in space based on the obtained actual bending angle.

[0045] In some embodiments, the plurality of optical waveguide sensors includes a first optical waveguide sensor, a second optical waveguide sensor, and a third optical waveguide sensor.

[0046] The relationship between the actual voltage signal and the bending angle corresponding to the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor respectively satisfies the conditional formula:

[0047] ,

[0048] ,

[0049] ,

[0050] Where θ˙ is the actual bending angle of the center of the Bowden cable, θ¨ is the actual bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when they are synchronously bent with the Bowden cable, and Y L1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor, wherein it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0051] In some embodiments, along the axis of the Bowden cable, multiple optical waveguide sensors are bonded around the outer circumference of the Bowden cable by EVA resin. It can be understood that the above conditional expressions are all normalized conditional expressions to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0052] In some embodiments, the end position estimation device further includes a light source assembly and a light intensity receiving device, wherein the first end of the Bowden cable is connected to the light source assembly, and the second end is connected to the light intensity receiving device. The first ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light source assembly, and the second ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light intensity receiving device, and the light intensity receiving device is electrically connected to the processing unit.

[0053] In some embodiments, the Bowden cable and the plurality of optical waveguides are fixedly connected to the light source assembly and the light intensity receiving device respectively through UV glue.

[0054] In some embodiments, the light source assembly includes a light source fixture and a red LED light source with a 15-degree lens disposed in the light source fixture, wherein the material of the light source fixture includes ABS mixed with glass fiber.

[0055] A specific example provided by the present disclosure is referred to as Figure 1-5 , including: the present invention distributes three optical waveguide sensors (a first optical waveguide sensor 2, a second optical waveguide sensor 3 and a third optical waveguide sensor 4) in a circular array on the outer surface of the Bowden cable 1 and sets them in a close fit, so that the optical waveguide sensors can bend synchronously with the bending changes of the Bowden cable.

[0056] The Bowden cable has a simple structure, which consists of a steel cable, a sheath and connectors at both ends. The Bowden cable is easy to maintain, low in cost and small in space. The Bowden cable itself has excellent flexibility, can adapt to complex layouts and motion trajectories, and is durable and easy to install and replace. In the present disclosure, the Bowden cable is mainly used to limit the stretching of the optical waveguide sensor material, allowing the optical waveguide sensor material to focus on measuring bending, and to protect the cable.

[0057] Three optical waveguide sensors are arranged in a circular array and attached to the surface of the Bowden cable, and adjacent optical waveguide sensors are arranged at a distance of 120° so as to bend synchronously with the bending change of the Bowden cable. In the present disclosure, the optical waveguide sensor has the characteristics of simple structure, low material price, outstanding anti-electromagnetic and sweat humidity interference ability, accurate measurement value, small and light size, small space occupation, and closer to the actual application environment during the bending process.

[0058] The light source uses a red LED light source with a 15-degree lens, and the wavelength of the light is 620-625nm. Red light is selected because it is easier to lose than white light in polyester materials, but it will not lose too much to cause a sudden drop in light intensity when bending. The light intensity receiving device has a photosensitive sensor, in which the photosensitive sensor uses a photodiode light detector. The photosensitive diode can filter infrared and prevent interference from invisible light. Specifically, the PD550A5F model photosensitive diode can be selected, which has the characteristics of high sensitivity.

[0059] The optical waveguide sensor consists of a high-refractive-index polyurethane elastomer core (core layer TPV) and a heat-shrinkable tube (cladding layer PET). The measurement principle of the optical waveguide sensor bending sensor: the bending of the optical waveguide sensor material will cause light intensity loss. The photosensitive diode measures the change in light intensity at the end of the material and obtains the required data based on the change in light intensity. Compared with the traditional strain gauge bending sensor, the cost of the optical waveguide sensor is only 1 / 10 of that of the strain gauge bending sensor at the same length, which greatly reduces the production cost.

[0060] The optical waveguide sensor has two parts, including the core layer TPV (refractive index n1) and the cladding layer PET (refractive index n2) (refractive index n1>n2). Due to their different refractive indices, light can propagate in the optical fiber core through reflection from the cladding. The basic principle of the optical waveguide sensor is that when light propagates into a medium with a lower refractive index, total reflection occurs, and the light beam will not escape during the transmission of the optical waveguide sensor, so that a single flexible optical waveguide sensor can be used to simultaneously detect bending and stretching deformations.

[0061] When light enters a medium with a lower refractive index (n2) from a medium with a higher refractive index (n1), if the incident angle is greater than a certain critical angle, the refracted light will disappear and all the incident light will be reflected without entering the medium with a higher refractive index.

[0062] The Bowden wire has high toughness and elasticity, which protects the optical waveguide sensor from being squeezed and stretched. Therefore, only the influence of bending on the optical waveguide sensor signal is considered, and the performance of the optical waveguide sensor under different bending states can be tested. In order to make the comparison of the optical waveguide sensor in the two forms more intuitive, the voltage of the signal modulation circuit when the optical waveguide sensor is not deformed is defined as , when the optical waveguide sensor is deformed, the voltage of the signal modulation circuit is U, so the signal loss ratio is defined as And the light intensity attenuation value DB is shown in formula (1):

[0063] ,

[0064] The voltage of the signal modulation circuit increases as the light intensity decreases, and the signal loss ratio can be obtained. The relationship between the light intensity attenuation value DB and the deformation: The greater the curvature of the optical waveguide sensor, The larger it is, the greater the curvature of the optical waveguide sensor is, and the greater the light intensity attenuation value DB is.

[0065] The end position estimation device disclosed in the present invention can be applied to an exoskeleton binding device. The present invention is to improve the accuracy and control efficiency of the kinematic model and dynamic model of the exoskeleton device, and enable the exoskeleton device to run to the target position more accurately. The optical waveguide sensor on the end position estimation device designed in the present invention captures real-time curvature data (actual bending angle) as the Bowden cable bends, and the spatial curvature information (actual bending angle) is calculated by the processing unit and then transmitted to the control module of the exoskeleton binding device used. Furthermore, the end position estimation device provides real-time joint position information data for the exoskeleton device, enhances the accuracy and control efficiency of the kinematic and dynamic models of the exoskeleton device, and enables the exoskeleton device to run to the target position more accurately. This technology is expected to bring positive application prospects in the fields of rehabilitation medicine and auxiliary equipment.

[0066] Specifically, Figure 1 An end position estimation device based on an optical waveguide sensor is shown, wherein three optical waveguide sensors include a first optical waveguide sensor 2, a second optical waveguide sensor 3 and a third optical waveguide sensor 4. The three optical waveguide sensors are centered on a Bowden cable 1, are parallel to the Bowden cable 1 and are fixed on the Bowden cable 1 in a circular array by bonding with EVA natural resin.

[0067] The three optical waveguide sensors and the Bowden wire have the same length. The first optical waveguide sensor 2 , the second optical waveguide sensor 3 and the third optical waveguide sensor 4 are each connected to a port of the processing unit through four wires, and the connector is an XH2.54 4P terminal.

[0068] When using EVA natural resin, the extrusion temperature is 105 degrees, and the waiting bonding time is 15 seconds. The above devices are connected by EVA natural resin to ensure the structural stability between the optical waveguide sensor and the Bowden cable.

[0069] Furthermore, the light source fixing device 5 and the light intensity receiving device 6 are both provided with holes, including a central hole and three edge holes arranged in a circular array around the central hole, the Bowden wire is arranged in the central hole, and the optical waveguide sensor is arranged in the edge hole.

[0070] Furthermore, the Bowden cable 1 and the optical waveguide sensor 2, the optical waveguide sensor 3 and the optical waveguide sensor 4 are fixedly connected to the light source fixing device 5 and the light intensity receiving device 6 through UV glue, and the two ends of the Bowden cable 1 are respectively fixed to the central holes of the light source fixing device 5 and the light intensity receiving device 6, and the two ends of the optical waveguide sensor 2, the optical waveguide sensor 3 and the optical waveguide sensor 4 are respectively fixed to the three edge holes of the light source fixing device 5 and the light intensity receiving device 6.

[0071] The light source fixing device 5 is made of ABS mixed glass fiber material printed by fused deposition molding technology, and three red LED light sources with 15-degree lenses are arranged inside it, and the three red LED light sources are bonded to the optical waveguide sensor correspondingly by UV glue.

[0072] The light intensity receiving device 6 is made of ABS mixed with glass fiber material printed by 3D printing technology, and is combined with three photosensitive diode light detectors by UV glue. The three photosensitive diode light detectors correspond to the optical waveguide sensor one by one and are in the same straight line. In the present disclosure, the UV glue connection can ensure that the high refractive index polyurethane elastomer core inside the optical waveguide sensor and the connection between the light source and the photosensitive diode are completely transparent, so that light can be transmitted inside the optical waveguide sensor.

[0073] Figure 2-4 , determine the end position of the Bowden cable in space, including:

[0074] like Figure 2 As shown, in the standard Cartesian coordinate system, on the xy plane and the yz plane, when the angle of the optical waveguide sensor concentrically arranged with the Bowden cable on the xz plane remains unchanged (in the Cartesian space, the x and z values ​​remain unchanged), the output voltage y1 corresponding to the bending angle θ˙ is measured, and a fitting curve is obtained by fitting the bending angle θ˙ and the output voltage y1.

[0075] The corresponding fitting curve is obtained by fitting the relationship between the output voltage y1 and the bending angle θ˙ on the xy and yz planes. The bending angles of the Bowden cable on the xy and yz planes are determined using the fitting curve, thereby inferring the preliminary end position of the plane.

[0076] Further, if Figure 3-4 As shown, in the standard Cartesian position system, on the xz plane (x, z values ​​change, y value remains unchanged), the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor are attached to the periphery of the Bowden wire in a circular array, and the output voltages y of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor at different bending angles θ¨ are measured respectively. L1 ,y L2 and L3 , and according to the bending angle θ¨ and the output voltage y L1 ,y L2 and L3 The relationship between them is fitted to obtain the corresponding fitting curves L1, L2, and L3.

[0077] Further, if Figure 5 As shown, according to the obtained fitting curves L1, L2, L3, the output voltage differences K1 and K2 between adjacent fitting curves are calculated, where K1=y L1−y L2 and K2=y L2 −y L3 .

[0078] The curvature model on the xz plane is established through the mapping relationship between the values ​​of K1 and K2 and the bending angle θ¨, and the end position of the Bowden cable in the xz plane is determined according to the bending angles determined on the xy plane and the yz plane and the curvature model established on the xz plane.

[0079] Specifically, Figure 2 As shown, the corresponding relationship between the output electrical signal y1 and the bending angle θ˙ satisfies the fitting condition:

[0080] (2),

[0081] It can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0082] like Figure 3 (y value is 240°) and Figure 4 (When any value of y occurs, the changes of L1, L2, and L3) and the output electrical signal y L1 ,y L2 and L3 The corresponding relationship between the bending angle θ¨ satisfies the following conditions:

[0083] (3),

[0084] (4),

[0085] (5), where it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert the different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

[0086] like Figure 5 As shown, the output voltage differences K1 and K2 between adjacent fitting curves satisfy the conditional formula:

[0087] (6),

[0088] (7),

[0089] Among them, it can be understood that the above conditional expressions are all normalized conditional expressions to convert different dimensions on both sides of the conditional expression into data of the same order of magnitude. In formula (2), θ˙ is the bending angle of the optical waveguide sensor set concentrically with the Bowden wire when the x- and z-axis values ​​of the end remain unchanged and the y-axis value changes, and θ¨ is the bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when the y-axis value of the end remains unchanged and the x- and z-axis values ​​change. By obtaining the relationship between the voltage value y1 and the bending θ˙, the mapping relationship between the voltage value and the bending angle of the end position of the optical waveguide sensor only when the y-value changes is deduced. By fixing the bending angle of the y-axis to 240° and only changing the x- and z-axis values, we get Figure 3 From formula (2), we can see that when θ˙ is 240°, the voltage value is 2.87. Figure 3 Subtract 2.87 from the three fitting curves in Figure 4 The fitting curve shown is Figure 4 When the fixed curvature on the y-axis is arbitrary, the voltage value y L1 ,y L2 and L3 The relationship between the voltage value and the bending angle θ¨ is derived from the relationship between the voltage value and the bending angle when the end position changes in the x-axis and z-axis values.

[0090] Furthermore, by comparing y L1 ,y L2 and L3 By analyzing the voltage changes of each optical waveguide sensor at different curvatures of the Bowden wire end in the xz plane, it can be found that under different curvatures, y L1 ,y L2 and L3 The corresponding values ​​are different, according to y L1 ,y L2 and L3 The difference between the fitting curves can be used to obtain the bending angle corresponding to the end position of the Bowden cable on the xz plane when the y value is arbitrary, that is, K1=y L1 −y L2 and K2=y L2 −y L3 .

[0091] Furthermore, since the three optical waveguide sensors (the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor) are located at different positions on the Bowden cable, when the Bowden cable is bent, the bending angles of the three optical waveguide sensors attached to the sides of the Bowden cable will be different. Based on this characteristic, the bending angles of the three optical waveguide sensors are intuitively presented as voltage values, so that the bending angle of the Bowden cable in space and its end position can be analyzed.

[0092] Specifically, based on (2) and (3), (4) and (5), equations (8), (9) and (10) are calculated. Equation 2 is the relationship between the bending angle and voltage of the Bowden cable itself. Equations 3, 4 and 5 are the relationship between the bending angle and voltage of the three optical waveguides attached to the Bowden cable when the three optical waveguides are bent with the Bowden cable. Equation 2 is coupled and added with equations 3, 4 and 5 respectively to obtain equations 8, 9 and 10, that is, Y L1 , Y L2 and Y L3 , when each optical waveguide is bent, Y L1 is the actual voltage of the first optical waveguide sensor, Y L2 is the actual voltage of the second optical waveguide sensor, Y L3 is the actual voltage of the third optical waveguide sensor, the voltage value Y L1 , Y L2 and Y L3 All can be directly measured.

[0093] (8),

[0094] (9),

[0095] (10),

[0096] Among them, it can be understood that the above conditional expressions are normalized conditional expressions to convert the different dimensions on both sides of the conditional expression into data of the same order of magnitude. After solving the values ​​of θ˙ and θ¨ using equations (8), (9) and (10) respectively, we can determine the bending angle of the Bowden cable in space and thus obtain the end position of the Bowden cable.

[0097] Compared with the traditional end position estimation device, the optimized end position estimation device disclosed in the present invention integrates multiple optical waveguide sensors with good anti-interference ability, which can measure the bending angle and voltage value change of the Bowden cable with high precision, and has the function of rapid customization. This data acquisition method enables the exoskeleton device to obtain the position information estimated by the end position estimation device in real time, thereby improving the accuracy and control efficiency of the kinematic model and dynamic model of the exoskeleton device, and enables the exoskeleton to correct the deviation in real time, so that the exoskeleton device can always run to the ideal target position. Not only that, it can also compensate for the friction between the inner wall of the Bowden cable and the wire rope in the Bowden cable transmission device in three-dimensional space.

[0098] First, the end position detection device disclosed in the present invention has high accuracy and real-time performance. Second, the end position estimation device disclosed in the present invention is based on an optical waveguide sensor and has extremely excellent anti-interference capabilities. Third, the end position estimation device we invented is small in size, light in weight, and highly portable. Fourth, the cost of the end position estimation device disclosed in the present invention is greatly reduced compared to the cost of the end position detection devices on the market.

[0099] The disclosed end position estimation device integrates multiple optical waveguide sensors, which can detect the cumulative bending angle of the Bowden cable in space and provide real-time joint position information data for the exoskeleton device, enhancing the accuracy and control efficiency of the kinematic and dynamic models of the exoskeleton device, and enabling the exoskeleton device to move to the target position more accurately. This technology is expected to bring positive application prospects in the fields of rehabilitation medicine and assistive devices.

[0100] refer to Figure 6 According to a second aspect of an embodiment of the present disclosure, a terminal position estimation method is provided. The estimation method is implemented according to any of the above terminal position estimation devices, and includes:

[0101] S101 . Acquire actual voltage signals corresponding to a plurality of optical waveguide sensors evenly spaced around the Bowden cable when the Bowden cable is bent.

[0102] S102: Calculate the actual bending angle based on each actual voltage signal and a preset voltage-bending angle relationship model.

[0103] S103, determining the end position of the Bowden cable according to the actual bending angle.

[0104] In some embodiments, the plurality of optical waveguide sensors includes a first optical waveguide sensor, a second optical waveguide sensor, and a third optical waveguide sensor.

[0105] The relationship between the actual voltage signal and the bending angle corresponding to the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor respectively satisfies the conditional formula:

[0106] ,

[0107] ,

[0108] ,

[0109] In the formula, it can be understood that the above conditional expressions are normalized conditional expressions to convert the different dimensions on both sides of the conditional expression into data of the same order of magnitude. θ˙ is the actual bending angle of the center of the Bowden cable, θ¨ is the actual bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when they are synchronously bent with the Bowden cable, and YL1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor.

[0110] According to a third aspect of the embodiments of the present disclosure, there is provided an exoskeleton binding device, the binding device comprising any of the above-mentioned end position estimation devices.

[0111] A fourth aspect of the embodiments of the present disclosure provides a computer-readable storage medium having a computer program stored thereon, characterized in that:

[0112] When the computer program is executed by a processor, the end position estimation method described above can be implemented.

[0113] The computer-readable medium may be included in the apparatus, device, or system of the present disclosure, or may exist independently.

[0114] Among them, computer-readable storage media can be any tangible media that contains or stores a program, which can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or equipment. More specific examples include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, an optical fiber, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0115] The computer-readable storage medium may also include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code, specific examples of which include but are not limited to electromagnetic signals, optical signals, or any suitable combination thereof.

[0116] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and substance of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. An end position estimation device, characterized in that: The end position estimation device includes a Bowden cable, a plurality of optical waveguide sensors evenly spaced along the circumference of the Bowden cable, and a processing unit electrically connected to the plurality of optical waveguide sensors; Each of the optical waveguide sensors is used to obtain an actual voltage signal corresponding to the bending of the Bowden cable; The processing unit is used to calculate the actual bending angle based on each of the actual voltage signals and a preset voltage-bending angle relationship model, so as to determine the end position of the Bowden cable according to the actual bending angle; The plurality of optical waveguide sensors include a first optical waveguide sensor, a second optical waveguide sensor, and a third optical waveguide sensor; The relationship between the actual voltage signal and the bending angle corresponding to the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor respectively satisfies the conditional formula: ， ， ， Wherein, θ˙ is the actual bending angle of the center of the Bowden cable, θ¨ is the actual bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when they are synchronously bent with the Bowden cable, and Y L1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor, wherein it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

2. The end position estimation device according to claim 1, characterized in that: Along the axial direction of the Bowden cable, the plurality of optical waveguide sensors are bonded around the outer circumference of the Bowden cable by means of EVA resin.

3. The end position estimation device according to claim 1, characterized in that: The end position estimation device further includes a light source assembly and a light intensity receiving device; the first end of the Bowden cable is connected to the light source assembly, and the second end is connected to the light intensity receiving device; The first ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light source assembly, the second ends corresponding to the plurality of optical waveguide sensors are respectively connected to the light intensity receiving device, and the light intensity receiving device is electrically connected to the processing unit.

4. The end position estimation device according to claim 3, characterized in that: The Bowden cable and the plurality of optical waveguides are fixedly connected to the light source assembly and the light intensity receiving device respectively through UV glue.

5. The end position estimation device according to claim 3, characterized in that: The light source assembly includes a light source fixing device and a red LED light source with a 15-degree lens arranged in the light source fixing device, wherein the material of the light source fixing device includes ABS mixed with glass fiber.

6. A method for estimating an end position, characterized in that: The estimation method is implemented according to the end position estimation device according to any one of claims 1 to 5, comprising: Acquire actual voltage signals corresponding to a plurality of optical waveguide sensors evenly spaced and arranged in a circumferential direction of the Bowden cable when the Bowden cable is bent; Based on each of the actual voltage signals and a preset voltage-bending angle relationship model, an actual bending angle is calculated; Determining the end position of the Bowden cable according to the actual bending angle; The plurality of optical waveguide sensors include a first optical waveguide sensor, a second optical waveguide sensor, and a third optical waveguide sensor; The relationships between the actual voltage signals and the bending angles corresponding to the first optical waveguide sensor, the second optical waveguide sensor, and the third optical waveguide sensor respectively satisfy the conditional formula: ， ， ， Wherein, θ˙ is the actual bending angle of the center of the Bowden cable, θ¨ is the actual bending angle of the first optical waveguide sensor, the second optical waveguide sensor and the third optical waveguide sensor when they are synchronously bent with the Bowden cable, and Y L1 is the voltage signal of the first optical waveguide sensor, Y L2 is the voltage signal of the second optical waveguide sensor, Y L3 is the voltage signal of the third optical waveguide sensor, wherein it can be understood that the above conditional expressions are all normalized conditional expressions, so as to convert different dimensions on both sides of the equal sign of the conditional expressions into data of the same order of magnitude.

7. An exoskeleton binding device, characterized in that: The binding device comprises the end position estimation device according to any one of claims 1-5.

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