A multi-dimensional force loading device for a plantar force sensor

Abstract

The application discloses a multi-dimensional force loading device for a plantar force sensor, which comprises a bottom plate, a vertical force loading device, a standard pressure sensor, a horizontal force loading device and an auxiliary device; the auxiliary device comprises a base, a mounting plate and a loading column; the horizontal force loading device comprises a rolling pulley, a wire rope and a weight, and when the horizontal force is loaded, the weight is connected with the loading column through the wire rope around the rolling pulley; the vertical force loading device comprises a ball screw rod; the vertical displacement of the ball is adjusted based on the threaded transmission, a force in the vertical direction is transmitted to the plantar force sensor to be calibrated through the loading column, and the loaded vertical force is measured by the standard pressure sensor. The application can realize the loading of the force in the vertical direction, the loading of the force in two horizontal directions and the loading of the force at different positions. The application can simulate the force range of the human plantar force, and the range of the force applied in the vertical direction is more than ten times of the range of the force applied in the horizontal direction.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of sensor, and relates to a technology for simulating multi-dimensional force loading, in particular to a multi-dimensional force loading device for a plantar force sensor. BACKGROUND

[0002] Plantar force refers to the reaction force generated by the interaction between the plantar and the ground during standing, walking, running and the like, and has significant time-varying and regional characteristics. It is one of important parameters in the fields of human motion, biomechanics, rehabilitation medicine, footwear design and the like. It mainly includes vertical force, forward-backward shear force and medial-lateral shear force. When a human body stands or walks, the peak value of the vertical force is about 1-1.3 times of the human body, and the peak values of the forward-backward shear force and the medial-lateral shear force are only 0.1-0.3 times of the human body.

[0003] At present, multi-dimensional force calibration platforms are mostly used for calibrating sensors with small differences in inter-dimensional ranges. For example, Chinese Patent No. ZL200810020511.4 discloses a method for calibrating a jack loading, which has the characteristic of large loading range. Chinese Patent Application Publication No. CN101936797A discloses a method for calibrating a multi-dimensional force sensor by using a weight loading mode, which is aimed at a multi-dimensional force sensor with small range. According to the characteristics of plantar force, the vertical force is ten times (loading range) of the shear force, and the plantar force has regional characteristics, i.e. the force position is variable. The inter-dimensional loading range of the existing multi-dimensional force loading device cannot achieve a ten-fold relationship, and the force position calibration cannot be achieved. SUMMARY

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application provides a multi-dimensional force loading device for a plantar force sensor, which is used to solve the technical problem that the loading range cannot achieve ten times. The present application solves the above-mentioned problem by setting a vertical force loading device and a horizontal force loading device.

[0005] To achieve the above-mentioned purpose, the present application provides a multi-dimensional force loading device for a plantar force sensor, which comprises,

[0006] a bottom plate, a vertical force loading device, a standard pressure sensor, a horizontal force loading device and an auxiliary device;

[0007] The auxiliary device comprises a base, a mounting plate and a loading column. The horizontal force loading device comprises a rolling pulley, a wire rope and a weight. When the horizontal force is loaded, the weight is connected with the loading column through the wire rope around the rolling pulley.

[0008] The vertical force loading device comprises a ball screw rod, when the vertical force is loaded, a standard pressure sensor is arranged between the ball of the ball screw rod and the loading column, the ball is in point-surface contact with the standard pressure sensor; the vertical displacement of the ball is adjusted based on the screw transmission, the force in the vertical direction is transmitted to the plantar force sensor to be calibrated through the loading column, and the loaded vertical force is measured by the standard pressure sensor.

[0009] Preferably, the bottom plate is a flat plate, an array of fixing holes are arranged around the flat plate for corresponding installation at different positions on the flat plate; the base is installed in the middle of the flat plate in a lifting manner; the mounting plate is connected to the upper side of the base for mounting the plantar force sensor to be calibrated; the loading column is installed at the bottom of the plantar force sensor to be calibrated;

[0010] The vertical force loading device further comprises a vertical column and a crossbeam;

[0011] The vertical column and the crossbeam constitute a frame structure for vertical force loading, and the crossbeam is provided with a threaded hole in the middle;

[0012] One end of the ball screw rod is a threaded rod, and the other end is a rollable ball;

[0013] One end of the ball screw rod is connected to the threaded hole of the crossbeam, and the ball at the other end is located directly above the loading column; by rotating the ball screw rod, the standard pressure sensor is aligned and abuts against, so that the ball of the ball screw rod and the standard pressure sensor are in point-surface contact.

[0014] Preferably, the loading column is provided with at least two annular grooves in the middle for horizontal force loading; the top of the loading column is provided as a force application position for vertical force loading; the top and the bottom of the loading column are provided with rectangular panels, the rectangular panel at the bottom is provided with a mounting hole, and the plantar force sensor to be calibrated is installed through the mounting hole.

[0015] Preferably, the ball screw rod is a bolt type universal steel ball roller.

[0016] Preferably, the fixing holes on the bottom plate are equidistant threaded holes, and the vertical force loading device and the horizontal force loading device are connected to the bottom plate through screws; by adjusting the installation position of the vertical force loading device and the bottom plate, the loading position of the vertical force is adjusted; by adjusting the installation position of the horizontal force loading device and the bottom plate, the loading position of the horizontal force is adjusted.

[0017] Preferably, the horizontal force loading device comprises at least two groups of rolling pulleys, two groups of rolling pulleys are arranged above the bottom plate on both sides of the base, and one-to-one correspond to the annular grooves of the loading column; the top wheel groove of the rolling pulley is consistent in height with the annular groove of the corresponding loading column, a wire rope is arranged on the rolling pulley, one end of the wire rope is connected to the annular groove of the corresponding loading column of the rolling pulley, and the other end is connected to the corresponding weight by passing through the rolling pulley; the wire rope between the loading column and the rolling pulley remains horizontal.

[0018] Preferably, the loading column is provided with two annular grooves, and the distance from the bottom surface of the loading column is h1 and h2 (h1>h2).

[0019] Preferably, the rolling pulley is installed above the bottom plate through a pulley support, a pulley shaft, and a shaft sleeve; the bottom of the pulley support is connected to the fixed hole through a screw, the pulley shaft is installed on the top of the pulley support through the shaft sleeve; and the rolling pulley is sleeved on the pulley shaft.

[0020] A method for using a multi-dimensional force loading device for a plantar force sensor, comprising:

[0021] Step one: install the plantar force sensor to be calibrated on the mounting plate;

[0022] Step two: load the vertical force, adjust the installation position of the vertical force loading device and the bottom plate along the length direction or the width direction of the plane of the plantar force sensor, install the loading column in the auxiliary device on the corresponding position of the plantar force sensor, adjust the loading position of the vertical force, calibrate the force application position, place the standard pressure sensor between the loading column and the ball screw rod, rotate the ball screw rod to make the ball abut against the standard pressure sensor, realize point-surface contact between the ball of the ball screw rod and the standard pressure sensor, apply the vertical force, conduct the vertical force to the plantar force sensor through the standard pressure sensor and the loading column, load the vertical force, and measure the loaded vertical force by the standard pressure sensor;

[0023] Step three: load the horizontal force, adjust the installation position of the horizontal force loading device and the bottom plate along the length direction or the width direction of the plane of the plantar force sensor, install the loading column in the auxiliary device on the corresponding position of the plantar force sensor, adjust the loading position of the horizontal force, calibrate the force application position, and install the horizontal force loading device at the position corresponding to the length direction or the width direction of the plane of the plantar force sensor;

[0024] Then, the corresponding weights of the weights on both sides of the loading column are m1 and m2, so that m1*h1=m2*h2, and the difference between m1 and m2 corresponds to the weight of the loaded horizontal force in the corresponding length direction or width direction.

[0025] Application of a multi-dimensional force loading device for a plantar force sensor in sensor calibration.

[0026] Compared with the prior art, the application has the following beneficial effects:

[0027] 1. The application can realize vertical force loading, two horizontal force loadings, and force loading at different positions. 2. The application can simulate the force range of human plantar force, and the vertical force range is more than ten times of the horizontal force range. 3. The vertical force loading device and the measured surface are point-surface contact, so that when a large vertical force is applied, no horizontal force is added, and the influence of the processing error of the vertical force loading device on the applied force error is eliminated. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0029] Figure 1 It is a structural schematic diagram of the application;

[0030] Figure 2 It is a structural schematic diagram of the vertical force loading device of the application;

[0031] Figure 3 It is a structural schematic diagram of the point-surface contact between the ball of the ball screw rod and the standard pressure sensor in the vertical force loading device of the application;

[0032] Figure 4 It is a structural schematic diagram of the rolling pulley in the horizontal force loading device;

[0033] Figure 5 It is a structural schematic diagram of the auxiliary device of the application;

[0034] Figure 6 It is a schematic diagram of horizontal force loading when the guide wheel between the loading column and the pulley assembly is located at the lowermost position in another embodiment;

[0035] Figure 7 It is a schematic diagram of horizontal force loading when the guide wheel between the loading column and the pulley assembly is located at the uppermost position in another embodiment;

[0036] The figure label: 1 bottom plate, 2 auxiliary device, 21 flange base, 22 mounting plate, 23 loading column, 3 vertical force loading device, 31 column, 32 crossbeam, 33 ball screw, 4 horizontal force loading device, 41 pulley support, 42 rolling pulley, 43 bolt shaft, 44 shaft sleeve, 45 support plate, 46 groove, 5 standard pressure sensor, 6 to be calibrated plantar force sensor, 7 guide wheel, 8 torque sensor. DETAILED DESCRIPTION

[0037] The technical solutions of the present application will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0038] Embodiment 1, please refer to Figures 1-5 The present application provides a kind of multi-dimensional force loading device for plantar force sensor, including bottom plate 1, auxiliary device 2, vertical force loading device 3, horizontal force loading device 4 and standard pressure sensor 5;Vertical force loading device 3 and horizontal force loading device 4 are fixedly connected in bottom plate 1;The bottom plate 1 is a plane plate, and array threaded hole is arranged on the surface of plane plate near the position of four around, for installing vertical force loading device 3 and horizontal force loading device 4 in corresponding position according to the need using bolt or screw;Convenient to adjust the position of exerting force.

[0039] Vertical force loading device 3 includes column 31, crossbeam 32 and ball screw 33;Two columns 31 are distributed in the two ends of crossbeam 32 respectively, and the two ends of crossbeam 32 are connected to the one end of corresponding column 31 by bolt vertically, and the other end of column 31 is connected to bottom plate 1 vertically;Threaded hole is formed in the middle of crossbeam 32 and is connected to the screw rod section of ball screw 33 by screw thread, in some embodiments, a plurality of threaded holes are uniformly formed in crossbeam 32, to facilitate position adjustment, in some embodiments, the ball screw 33 can be screw type universal ball, and the model of ball screw 33 is BCHL hexagonal bolt steel ball roller or BCHLJ hexagonal bolt steel ball roller.

[0040] The lower side of ball screw 33 is provided with auxiliary device 2, auxiliary device 2 is installed on bottom plate 1, standard pressure sensor 5 is clamped between auxiliary device 2 and ball screw 33;Make ball abut standard pressure sensor, point-face contact is realized between the ball of ball screw and standard pressure sensor, when vertical force is loaded by rotating ball screw 33, vertical displacement is realized based on screw thread transmission fine adjustment of ball screw 33, force in vertical direction is applied to standard pressure sensor 5, and the reading of standard pressure sensor 5 is obtained, that is, the size of vertical force is obtained.

[0041] The auxiliary device 2 comprises a base 21, a mounting plate 22 and a loading column 23, the loading column 23 is a loading piece, the two ends of the base 21 are fixedly connected with the mounting plate 22 and the bottom plate 1 respectively, the base 21 can be provided with multiple heights to meet the needs of different heights, and the height can be adjusted by adding a shim between the base 21 and the bottom plate 1; the loading column 23 is located above the mounting plate 22 and one end thereof is in contact with the standard pressure sensor 5, and the other end of the loading column 23 is installed with the to-be-calibrated plantar force sensor 6 between the mounting plate 22, and the to-be-calibrated plantar force sensor 6 and the vertical force loading device 3 and the horizontal force loading device 4 are moved to realize the loading of corresponding forces in different positions and directions.

[0042] The loading column 23 is a cylindrical body with two annular grooves 231 formed on the outer surface (the annular grooves 231 are coaxially arranged with the loading column 23), and rectangular panels are welded on the upper and lower ends of the cylindrical body, the rectangular panel at the lower end of the cylindrical body is provided with a mounting hole and is installed on the to-be-calibrated sensor to assist in applying force.

[0043] The horizontal force loading device 4 comprises two groups of pulley assemblies, and the two groups of pulley assemblies are arranged on the two sides of the vertical force loading device 3; the pulley assembly comprises a pulley support 41, a rolling pulley 42, a bolt shaft 43 and a shaft sleeve 44, a groove 46 is formed on the top end face of the pulley support 41, the groove 46 is arranged vertically to the plane on which the vertical force loading device 3 is arranged, and the two ends of the groove 46 are arranged through the opposite two faces of the pulley support. Figure 1 The rolling pulley 42 of each pulley support 41 is installed on the side away from the vertical force loading device 3.

[0044] One of the pulley supports 41 is higher than the other, and the bottom surfaces of the two grooves 46 are respectively lower than the heights of the two annular grooves 231 (the height of one of the grooves 46 is between the heights of the two annular grooves 231, and the height of the other groove 46 is lower than the heights of the two annular grooves); the wheel groove (the point where the uppermost horizontal tangent in the wheel groove profile intersects with the wheel groove profile) of each rolling pulley 42 is consistent with the height of one annular groove 231.

[0045] Both ends of the rolling pulley 42 are provided with a support plate 45 connected to the surface of the pulley support 41, one end of the bolt shaft 43 is sequentially threaded through the support plate 45, the shaft sleeve fixed in the center of the rolling pulley 42 and the other support plate 45 on the other side, and then is threadedly connected with a nut to realize positioning, and the shaft sleeve 44 is fixedly connected to the inner wall of the through hole formed at the axial position of the rolling pulley 42.

[0046] The heights of the two annular grooves 231 of the loading column 23 from the lower end face are h1 and h2 (h1>h2), respectively; when a horizontal force is loaded, one end of a wire rope is fixed on the higher annular groove 231 of the loading column 23, the other end of the wire rope passes through the groove 46 of the higher pulley support 41 and the wheel groove of the rolling pulley 42, and hangs a weight m1. One end of another wire rope is fixed on the lower annular groove 231 of the loading column 23, and the other end of the wire rope passes through the groove 46 of the lower pulley support 41 and the wheel groove of the rolling pulley 42, and hangs a weight m2; the mass of the two ends of the weight needs to satisfy m1*h1=m2*h2, and the weight of the m2 weight minus the weight of the m1 weight is the horizontal loading force. In some embodiments, the wire rope is a steel wire rope.

[0047] The embodiment provides a use method of the multi-dimensional force loading device for the plantar force sensor:

[0048] The use method comprises the following steps:

[0049] Step two: vertical force loading is performed, the installation position of the vertical force loading device and the bottom plate is adjusted along the length direction or the width direction of the plane of the plantar force sensor, the loading column in the auxiliary device is installed at the corresponding position of the plantar force sensor, the loading position of the vertical force is adjusted, the position of the applied force is calibrated, the standard pressure sensor is arranged between the loading column and the ball screw rod, the ball screw rod is rotated to make the ball abut against the standard pressure sensor, point-surface contact is realized between the ball of the ball screw rod and the standard pressure sensor, the vertical force is applied, the vertical force is conducted to the plantar force sensor through the standard pressure sensor and the loading column, the vertical force loading is performed, and the loaded vertical force is measured by the standard pressure sensor.

[0050] Step three: horizontal force loading is performed, the installation position of the horizontal force loading device and the bottom plate is adjusted along the length direction or the width direction of the plane of the plantar force sensor, the loading column in the auxiliary device is installed at the corresponding position of the plantar force sensor, the loading position of the horizontal force is adjusted, the position of the applied force is calibrated, and the horizontal force loading device is installed at the position corresponding to the length direction or the width direction of the plane of the plantar force sensor.

[0051] Then, when the corresponding mass of the weights on both sides of the loading column is m1 and m2, and m1*h1=m2*h2, the difference between m1 and m2 corresponds to the weight of the horizontal force loaded in the length direction or the width direction.

[0052] In order to conveniently perform horizontal force loading, in the embodiment 1, please refer to Figure 6 and 7The embodiment provides: on one side of the loading column 23, a guide pulley 7 capable of being adjusted up and down is arranged between the loading column 23 and the pulley assembly;

[0053] When the guide pulley 7 is located at the lower side of the rolling pulley 42 of the corresponding pulley assembly, the wire rope between the corresponding guide pulley 7 and the loading column 23 is in abutment at the lower side of the guide pulley 7; when the guide pulley 7 is located at the upper side of the rolling pulley 42 of the corresponding pulley assembly, the wire rope between the corresponding guide pulley 7 and the loading column 23 is in abutment at the upper side of the guide pulley 7;

[0054] A torque sensor 8 is arranged at the bottom of the loading column 23 to adjust the position of the guide pulley 7; when the torque sensor 8 shows that the torque at the bottom of the loading column is 0, that is, the torque vector sum of the forces of the weights on both sides at the bottom of the loading column is 0, the horizontal inclination angle θ of the wire rope between the guide pulley 7 and the loading column 23 is measured (the horizontal inclination angle θ is the angle between the wire rope and the horizontal direction); at this time, the weight of the weight hanging on the wire rope is M, Mcosθ is the weight of the weight of the corresponding pulley assembly, and the difference between the weight of the weight hanging on the wire rope on the other side and the weight of the weight hanging on the wire rope on the other side corresponds to the horizontal loading force, and Msinθ is the additional vertical loading force at this time.

[0055] The above embodiment is only used to illustrate the technical method of the present application and is not limited. Although the present application is described in detail with reference to the preferred embodiment, it should be understood by those skilled in the art that the technical method of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical method of the present application.

Claims

1. A multi-dimensional force loading device for a plantar force sensor, characterized in that: include, Base plate, vertical force loading device, standard pressure sensor, horizontal force loading device and auxiliary device; The auxiliary device includes a base, a mounting plate and a loading column; the horizontal force loading device includes a rolling pulley, a rope and a weight. When the horizontal force is loaded, the weight is connected to the loading column through the rope passing around the rolling pulley; The vertical force loading device includes a ball screw rod. When the vertical force is loaded, a standard pressure sensor is placed between the ball of the ball screw rod and the loading column, and the ball and the standard pressure sensor are in point-to-surface contact. The vertical displacement of the ball is fine-tuned based on the threaded transmission, and the vertical force applied is transmitted to the plantar force sensor to be calibrated via the loading column, and the loaded vertical force is measured by the standard pressure sensor. The base plate is a flat plate with an array of fixing holes arranged around it for corresponding installation at different positions on the base plate. The base is arbitrarily installed in the middle of the base plate. The mounting plate is connected to the upper side of the base and is used to install the plantar force sensor to be calibrated. The bottom of the loading column is installed on the plantar force sensor to be calibrated. The vertical force loading device also includes a column and a beam; The columns and beams constitute a frame structure for vertical force loading, and a threaded hole is provided in the middle of the beam; One end of the ball thread rod is a threaded rod, and the other end is a rollable ball; One end of the ball screw rod is connected to the threaded hole of the beam, and the ball at the other end is located directly above the loading column. By rotating the ball screw rod and aligning it with the standard pressure sensor, point-to-surface contact is achieved between the ball of the ball screw rod and the standard pressure sensor. The middle of the loading column is provided with at least two annular grooves for horizontal force loading; the top of the loading column is set as a force application position for vertical force loading; The top and bottom of the loading column are provided with rectangular panels, and the rectangular panel at the bottom is provided with mounting holes, through which the plantar force sensor to be calibrated is mounted.

2. A multi-dimensional force loading device for a plantar force sensor according to claim 1, characterized in that: The ball threaded rod is a bolt-type universal steel ball roller.

3. A multi-dimensional force loading device for a plantar force sensor according to claim 2, characterized in that: The fixing holes on the base plate are equally spaced threaded holes, and the vertical force loading device and the horizontal force loading device are connected to the base plate by screws; the vertical force loading position is adjusted by adjusting the installation position of the vertical force loading device and the base plate; the horizontal force loading position is adjusted by adjusting the installation position of the horizontal force loading device and the base plate.

4. A multi-dimensional force loading device for a plantar force sensor according to claim 3, characterized in that: The horizontal force loading device includes at least two groups of rolling pulleys, which are arranged above the bottom plate on both sides of the base and correspond one to one to the annular grooves of the loading columns; the top wheel grooves of the rolling pulleys are consistent in height with the annular grooves of the corresponding loading columns, and a rope is configured on the rolling pulley, one end of the rope is connected to the annular groove of the loading column corresponding to the rolling pulley, and the other end passes around the rolling pulley and is connected to the corresponding weight; the rope between the loading column and the rolling pulley is kept horizontal.

5. The multi-dimensional force loading device for a plantar force sensor according to claim 4, characterized in that: The loading column is provided with two annular grooves, the heights of which from the bottom surface of the loading column are h1 and h2 (h1>h2).

6. A multi-dimensional force loading device for a plantar force sensor according to claim 5, characterized in that: The rolling pulley is installed above the base plate through a pulley bracket, a pulley shaft and a shaft sleeve; the bottom of the pulley bracket is connected to the fixing hole through a screw, and the pulley shaft is installed on the top of the pulley bracket through the shaft sleeve; the rolling pulley is sleeved on the pulley shaft.

7. A method for using the multi-dimensional force loading device for a plantar force sensor according to claim 5 or 6, characterized in that: include: Step 1: Install the plantar force sensor to be calibrated on the mounting plate; Step 2: Loading the vertical force, adjusting the installation position of the vertical force loading device and the base plate along the length direction or width direction of the plane of the plantar force sensor, and installing the loading column in the auxiliary device at the corresponding position of the plantar force sensor, adjusting the loading position of the vertical force, and calibrating the force application position; placing the standard pressure sensor between the loading column and the ball screw rod, rotating and adjusting the ball screw rod so that the ball abuts the standard pressure sensor, and achieving point-surface contact between the ball of the ball screw rod and the standard pressure sensor, applying the vertical force, and transmitting it to the plantar force sensor through the standard pressure sensor and the loading column, loading the vertical force, and measuring the loaded vertical force by the standard pressure sensor; Step 3: Apply horizontal force by adjusting the installation position of the horizontal force loading device and the base plate along the length or width direction of the plantar force sensor plane, and installing the loading column of the auxiliary device at the corresponding position of the plantar force sensor to adjust the horizontal force loading position; calibrate the force application position; Install a horizontal force loading device at a position corresponding to the length direction or width direction of the plane of the plantar force sensor; Then, the corresponding weight masses on both sides of the loading column are m1 and m2, so that when m1*h1=m2*h2, the weight corresponding to the difference between m1 and m2 is the horizontal force loaded in the corresponding length direction or width direction.

8. Use of the multi-dimensional force loading device for a plantar force sensor according to any one of claims 1 to 6 in sensor calibration.

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