Analog device and method for detecting foot movement speed and direction

Abstract

This invention relates to a simulation device and method for detecting the speed and direction of foot movements, belonging to the field of virtual reality technology. The simulation device uses a chassis as a mounting carrier, within which multiple sensing modules are arrayed. In each sensing module, a sphere is supported by two working shafts and one supporting shaft arranged in a triangular configuration, with the two working shafts perpendicular to each other. When the user runs or walks, the sphere drives the working and supporting shafts to rotate. A magnetic ring is placed at the end of each working shaft, and a Hall effect sensor is arranged near the magnetic ring. When the working shafts rotate, the signal from the Hall effect sensor reflects the rotational speed of the shafts. The vector sum of the rotational speeds of the two working shafts represents the sphere's rotational speed, including both speed and direction information. This invention eliminates the need for image processing, directly sensing the rotational state of the shafts through the Hall effect, achieving accurate recognition even for micron-level rotations, thus solving the problem of optical sensing easily missing small-step turning and low-speed walking motion signals.

Description

Technical Field

[0001] This invention relates to the field of virtual reality technology, and in particular to a simulation device and method for detecting the speed and direction of foot movements. Background Technology

[0002] Currently, when virtual reality (VR) technology is applied to shooting games, a large activity area is usually required for the players. If the area is insufficient, on the one hand, the chances of players running out of the area and having an accident will increase, and on the other hand, players will often be forced to retreat because they have moved to the boundary of the area, and cannot fully play their game.

[0003] Existing technology CN210038711U provides a VR human-computer interaction chassis with orientation dynamic sensing. Multiple Hall effect units are evenly arranged on the chassis. Each Hall effect unit comprises a rolling ball, a ball holder, and a ball motion sensor. The rolling ball slides on the ball holder, and the ball motion sensor is disposed within the ball holder. A cover plate is provided above the ball holder, and the upper part of the rolling ball passes through a limiting ball opening in the cover plate. The ball motion sensor is composed of optical and photoelectric sensors, and the rolling ball is a uniformly diffuse reflective sphere. An electronic image information processing unit maps the detected values ​​of the rolling direction, rolling amount, and rolling speed of each rolling ball into a virtual space, forming the virtual space's human movement direction, step distance, and movement speed status.

[0004] The aforementioned VR human-computer interaction chassis uses an optical sensing solution. During long-term use, dust generated from wear on the ball's surface and environmental dust adhere to the sensor surface, easily obstructing the light path and causing missed steps and misjudgments in motion recognition. Secondly, this VR human-computer interaction chassis requires the use of photosensitive devices to capture the grayscale changes in the diffuse reflection image from the ball's surface, and then uses image processing algorithms to calculate the ball's rotation direction and speed. The detection accuracy of this type of solution is limited by the pixel density and sampling frame rate of the photosensitive devices, making it difficult to capture the micron-level displacements produced by the ball during low-speed rolling. When the user performs subtle movements such as small turns or slow walks, motion signals are easily missed.

[0005] Therefore, it is necessary to further optimize the sensing elements for detecting the rolling direction, rolling amount, and rolling speed of the ball to improve detection accuracy and reduce the possibility of missed detections and false judgments. Summary of the Invention

[0006] To address the shortcomings of related technologies, this invention provides a simulation device and method for detecting the speed and direction of foot movements. The simulation device uses a chassis as its mounting carrier, within which multiple sensing modules are arrayed. Each sensing module contains a sphere supported by two working shafts arranged in a triangle and one supporting shaft, with the two working shafts perpendicular to each other. When the user runs or walks, the sphere drives the working and supporting shafts to rotate. A magnetic ring is placed at the end of each working shaft, and a Hall effect sensor is positioned near the magnetic ring. The signal from the Hall effect sensor reflects the rotational speed of the working shafts. The vector sum of the rotational speeds of the two working shafts represents the sphere's rotational speed, including both rate and direction information. This invention directly senses the rotational state of the shafts through the Hall effect, achieving accurate identification even for micron-level rotations, thus solving the problem of optical sensing easily missing small-step turning and low-speed walking motion signals.

[0007] This invention provides a simulation device for detecting the speed and direction of foot movement, including a chassis and multiple sensing modules arranged in an array within the chassis; the sensing modules include: a sphere, a bracket, a limiting cover, a working shaft, a supporting shaft, and a Hall effect unit; The sphere is supported by two working shafts and one support shaft arranged in a triangle. Each working shaft is horizontal and rotatably connected to a bracket at both ends, and the support shaft is horizontal and connected to a bracket at both ends. The two working shafts are perpendicular to each other. Each working shaft corresponds to a Hall unit mounted on the bracket. The Hall unit includes a magnetic ring mounted on the end of the working shaft and two Hall sensors mounted on the bracket at the same distance from the magnetic ring. The sensing surfaces of the two Hall sensors are parallel to the working shafts and perpendicular to each other. A limiting cover is provided with a limiting hole with a diameter smaller than that of the sphere. The limiting cover is detachably connected to the bracket, and the top of the sphere extends out of the limiting hole from the limiting cover.

[0008] In some embodiments, the chassis is provided with multiple sets of sensing modules along its own radial direction, and each set of sensing modules includes multiple sensing modules evenly distributed around the center of the chassis; each sensing module has a working axis perpendicular to the radial direction of the chassis.

[0009] In some embodiments, the sensing module further includes bearings; the two ends of the working shaft are respectively connected to the bracket via two bearings, and the two ends of the support shaft are respectively connected to the bracket via two bearings; neither the working shaft nor the support shaft makes frictional contact with the bracket and the limiting cover.

[0010] In some embodiments, the chassis includes a cavity and a cover plate. The top of the cavity has an opening, and the sensing modules are all located inside the cavity. The cover plate is detachably connected to the cavity and covers the opening. The cover plate has positioning holes that correspond one-to-one with the spheres, and the top of the spheres extends out of the chassis from the corresponding positioning holes. The Hall unit also includes a circuit board, and two Hall sensors are arranged on the circuit board. The two circuit boards are detachably connected to the outside of the bracket. There is a gap between the bottom edge of the circuit board and the bottom surface of the cavity.

[0011] In some embodiments, the magnetic ring and Hall unit are located completely below the limiting cover, the top edge of the limiting cover extends upward to form a waterproof edge, the waterproof edge is provided with at least one drain outlet, and all drain outlets are arranged in a staggered manner with respect to the Hall unit and the magnetic ring.

[0012] In some embodiments, the sensing module further includes locking bolts, with one locking bolt on the side of each working shaft away from the sphere and one locking bolt on the side of the support shaft away from the sphere; the locking bolts pass through the threaded connection bracket of the limit cover; in the sensing module, three drain outlets are provided, and the three drain outlets are respectively aligned with the three locking bolts.

[0013] In some embodiments, the sensing module further includes a mounting bolt and a limiting protrusion; the bottom of the bracket is provided with a mounting through hole and a limiting through hole that matches the shape of the limiting protrusion; the bottom end of the mounting bolt passes through the mounting through hole and is threaded to the chassis; the limiting protrusion is fixed to the chassis and inserted into the limiting through hole.

[0014] In some embodiments, the edge of the limiting hole extends upward to form a limiting ring that mates with the spherical surface of the sphere, and the top of the sphere extends out of the limiting ring.

[0015] In some embodiments, the outer wall of the support is provided with stiffening plates, and wiring grooves are formed on the stiffening plates.

[0016] In some embodiments, a method for detecting foot movement speed and direction is also provided. When a user runs or walks on the simulation device for detecting foot movement speed and direction described in any of the above embodiments or any combination of embodiments, the balls drive the working shaft and the support shaft to rotate. The rotation speed of each ball is calculated separately, and the rotation speed includes direction and rate. Based on the rotation speed of all balls, the user's movement speed, including rate and direction, is calculated. The formula for calculating the speed V of the working shaft is as follows:

[0017] When the working shaft rotates, the two Hall sensors of the corresponding Hall unit will output two orthogonal square waves. When the phase difference between the two square waves is positive, the rotation direction of the working shaft is recorded as positive; when the phase difference between the two square waves is negative, the rotation direction of the working shaft is recorded as negative. r represents the radius of the working shaft, and T represents the period of the square wave. Calculate the rotational velocity vectors of the two working shafts and the rotational velocity of the ball.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses a chassis as the mounting carrier, with multiple sensing modules arrayed within the chassis. Each sensing module contains a sphere supported by two working shafts arranged in a triangle and one supporting shaft, with the two working shafts perpendicular to each other. When the user runs or walks, the sphere drives the working and supporting shafts to rotate. A magnetic ring is placed at the end of each working shaft, and a Hall effect sensor is positioned near the magnetic ring. The signal from the Hall effect sensor reflects the rotational speed of the working shaft as it rotates. The vector sum of the rotational speeds of the two working shafts represents the sphere's rotational speed, including both rate and direction information. This invention directly senses the rotational state of the shafts through the Hall effect, achieving accurate identification even for micron-level rotations, thus solving the problem of optical sensing easily missing motion signals such as small-step turns and low-speed walks.

[0019] 2. This invention limits each sensing module to have a working axis perpendicular to the radial direction of the chassis. This structural design allows all sensing modules to have completely uniform motion detection sensitivity in the radial direction. The motion data collected by sensing modules at different positions have extremely high consistency. During subsequent data fusion, there is no need to perform complex deviation calibration on sensing modules at different positions. This reduces the computational load of the background algorithm and avoids directional detection deviation caused by layout asymmetry, making the final output of the user's movement speed and direction more closely match the real motion state.

[0020] 3. The present invention extends the top edge of the limiting cover upward to form a waterproof edge. The waterproof edge is provided with a drain outlet that is staggered from the drain outlet of the Hall unit and the magnetic ring. When beverages, sweat or other liquids are accidentally spilled on the surface of the simulation device, the liquid will only flow along the gap of the cover plate to the top of the limiting cover. Under the protection of the waterproof edge, it will not flow directly to the Hall unit and magnetic ring area below. The liquid will then be discharged from the side through the staggered drain outlet. This achieves indirect waterproofing of the electronic component area from a structural level, completely avoiding the problem of short circuit and burnout caused by liquid directly contacting the Hall unit circuit board. This greatly improves the operational safety of the device in complex scenarios such as VR experience halls where there are dense crowds and users sweat a lot. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a perspective view of the sensing module in a specific embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the positions of the two working shafts in a specific embodiment of the present invention; Figure 3 for Figure 1 Top view of the induction module; Figure 4 for Figure 1Bottom view of the induction module; Figure 5 for Figure 4 Enlarged view of region A in the middle; Figure 6 This is a schematic diagram illustrating the mounting groove and the clearance groove in a specific embodiment of the present invention; Figure 7 This is a schematic diagram of a simulation device for detecting the speed and direction of foot movement in one specific embodiment of the present invention; Figure 8 for Figure 7 A schematic diagram of the internal structure of a simulation device used to detect the speed and direction of foot movements; Figure 9 This is a schematic diagram illustrating the calculation of the rolling ball speed in a specific embodiment of the present invention.

[0022] In the diagram: 1. Chassis; 11. Cavity; 12. Cover plate; 2. Sensing module; 21. Sphere; 22. Bracket; 221. Limiting through hole; 222. Mounting groove; 223. Clearance groove; 23. Limiting cover; 231. Limiting ring; 232. Waterproof edge; 233. Drain outlet; 24. Working shaft; 25. Supporting shaft; 26. Hall unit; 261. Magnetic ring; 262. Hall sensor; 263. Circuit board; 27. Bearing; 28. Connecting bolt; 29. ​​Locking bolt; 210. Mounting bolt; 211. Rib plate; 2111. Wiring groove; 212. Limiting protrusion; 3. Support foot. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] In the description of this invention, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] In this invention, the term "velocity" is a vector term that includes both speed and direction information.

[0028] like Figure 1-8 As shown, in an illustrative embodiment of the simulation device and method for detecting foot movement speed and direction of the present invention, the simulation device for detecting foot movement speed and direction includes a chassis 1 and a plurality of sensing modules 2 arranged in an array within the chassis 1; the sensing module 2 includes: a ball 21, a bracket 22, a limiting cover 23, a working shaft 24, a supporting shaft 25, and a Hall unit 26. The sphere 21 is supported by two working shafts 24 arranged in a triangle and a support shaft 25. Each working shaft 24 is horizontal and rotatably connected to a bracket 22 at both ends. The support shaft 25 is horizontal and connected to the bracket 22 at both ends. The two working shafts 24 are perpendicular to each other. Each working shaft 24 corresponds to a Hall unit 26 installed on the bracket 22. The Hall unit 26 includes a magnetic ring 261 installed at the end of the working shaft 24 and two Hall sensors 262 installed on the bracket 22 with the same spacing from the magnetic ring 261. The sensing surfaces of the two Hall sensors 262 are parallel to the working shafts 24 and perpendicular to each other. The limiting cover 23 is provided with a limiting hole with a diameter smaller than that of the sphere 21. The limiting cover 23 is detachably connected to the bracket 22. The top of the sphere 21 extends out of the limiting hole from the limiting cover 23.

[0029] The aforementioned simulation device uses chassis 1 as the mounting carrier. Multiple sensing modules 2, arrayed within chassis 1, can fully cover the foot-stepping area, ensuring that foot movements under different standing postures can be effectively collected. Each sensing module 2 adopts a triangular support structure consisting of a sphere 21, a bracket 22, a limiting cover 23, two working shafts 24, and a supporting shaft 25. The perpendicular arrangement of the two working shafts 24 enables independent sampling of two-dimensional motion in a plane, avoiding the problem of missing motion dimensions caused by single-axis detection. A magnetic ring 261 is installed at the end of each working shaft 24, which, together with two Hall sensors 262 on the bracket 22 with sensing surfaces parallel to and perpendicular to the working shafts 24, completely eliminates the optical path structure relied upon by traditional optical detection. This fundamentally eliminates the detection failure problem caused by wear and tear of the sphere and environmental dust obstructing the optical path, significantly improving hardware stability. The limiting cover 23 constrains the ball 21 through a limiting hole with a diameter smaller than that of the ball 21. The top of the ball 21 extends out of the limiting hole, ensuring that the ball 21 will not fall out of the bracket 22 during rolling, and also ensuring that the foot pressure can be smoothly transmitted to the ball 21 to drive its rotation. The entire structure requires no image processing and directly senses the rotation state of the shaft through the Hall effect. It can accurately identify even micron-level rotations, solving the problem that optical sensing is prone to missing small-step turning and low-speed walking motion signals. The detection accuracy and environmental interference resistance have achieved a qualitative leap, and it can be widely adapted to application scenarios with extremely high requirements for the reliability of foot movement detection, such as VR shooting games.

[0030] In some embodiments, the chassis 1 is provided with multiple sets of sensing modules 2 along its own radial direction. Each set of sensing modules 2 includes multiple sensing modules 2 evenly distributed around the center of the chassis 1. Each sensing module 2 has a working shaft 24 perpendicular to the radial direction of the chassis 1.

[0031] The multi-layered, surrounding array arrangement of the sensing modules 2 enables complete coverage of the entire chassis 1 without any blind spots. Whether the user is turning or stepping in the center or edge of the chassis 1, a sufficient number of spheres 21 can simultaneously collect motion signals, preventing data loss due to insufficient sampling density in local areas. Furthermore, each sensing module 2 has a working axis 24 perpendicular to the radial direction of the chassis 1. This design ensures uniform motion detection sensitivity across all sensing modules 2 in the radial direction. When the user moves radially along the chassis 1, the vertical radial working axes 24 of all corresponding sensing modules 2 will not idle. Another set of radially arranged working axes 24 can simultaneously output motion components. The motion data collected by sensing modules 2 at different locations exhibits extremely high consistency. Subsequent data fusion eliminates the need for complex deviation calibration of sensing modules 2 at different locations, reducing the computational load on the backend algorithm and avoiding directional detection deviations caused by layout asymmetry. This results in a final output of the user's movement speed and direction that more closely matches the actual motion state.

[0032] In some embodiments, the sensing module 2 further includes bearings 27; the two ends of the working shaft 24 are respectively connected to the bracket 22 by two bearings 27, and the two ends of the supporting shaft 25 are respectively connected to the bracket 22 by two bearings 27; neither the working shaft 24 nor the supporting shaft 25 has frictional contact with the bracket 22 and the limiting cover 23.

[0033] If the shaft directly mates with the 22 holes of the bracket, wear and jamming will occur at the contact points after long-term operation. The rotational resistance of the shaft will continue to increase with the duration of use, which will not only reduce the response speed of motion detection, but also cause the shaft to spin and lose steps due to uneven distribution of frictional resistance.

[0034] With the bearing 27 used for transitional connection, the frictional resistance during the rotation of the working shaft 24 and the support shaft 25 is reduced to an extremely low level. Even with the slightest foot rubbing motion by the user, the tiny rolling of the ball 21 can smoothly drive the working shaft 24 to rotate, and the Hall unit 26 can quickly capture the corresponding motion signal, completely eliminating the signal loss caused by shaft jamming under small displacement. At the same time, the structural design that prevents the shaft from contacting the bracket 22 and the limit cover 23 also avoids the problem of metal and plastic debris generated by long-term friction entering the detection area of ​​the Hall unit 26 and interfering with the magnetic field of the magnetic ring 261, further improving the long-term operational reliability of the entire sensing module 2, significantly extending the overall service life of the equipment, and reducing the frequency and cost of daily maintenance.

[0035] Furthermore, the bracket 22 is provided with an upward-facing mounting groove 222 with a bottom diameter matching that of the bearing 27. The mounting groove 222 corresponds one-to-one with the bearing 27, and each bearing 27 is inserted into the corresponding mounting groove 222. The side wall of the bracket 22 is provided with an upward-facing clearance groove 223, which corresponds one-to-one with the working shaft 24. Each working shaft 24 passes through the corresponding clearance groove 223 and is connected to the magnetic ring 261. Each working shaft 24 can move longitudinally reciprocally in and out of the corresponding clearance groove 223.

[0036] In some embodiments, both the working shaft 24 and the supporting shaft 25 are stepped shafts. Two bearings 27 and a magnetic ring 261 connected to the working shaft 24 are fitted onto the working shaft 24 and respectively abut against different shoulders of the working shaft 24. Two bearings 27 connected to the supporting shaft 25 are fitted onto the supporting shaft 25 and respectively abut against different shoulders of the supporting shaft 25.

[0037] In some embodiments, the Hall unit 26 further includes a circuit board 263, on which two Hall sensors 262 are arranged. The circuit board 263 serves as a carrier for the two Hall sensors 262. By pre-fixing the Hall sensors 262 onto the circuit board 263, the positioning and calibration of the sensors can be completed during the production process. This ensures that the positional accuracy of the two Hall sensors 262 fully meets the requirements of being perpendicular to each other and spaced consistent with the magnetic ring 261, avoiding the positional offset problem that occurs when manually soldering a single Hall element.

[0038] Furthermore, the circuit board 263 is mounted to the bracket 22 by multiple connecting bolts 28.

[0039] In some embodiments, two circuit boards 263 are detachably connected to the outside of the bracket 22; this external installation method completely avoids the rotating shaft movement area inside the bracket 22, and does not occupy the movement space of the ball 21 and the rotating shaft. At the same time, the detachable installation design makes it convenient to replace the faulty circuit board 263 separately without having to replace the entire sensing module 2.

[0040] In some embodiments, the chassis 1 includes a cavity 11 and a cover plate 12. The top of the cavity 11 is provided with an opening, and the sensing modules 2 are all located inside the cavity 11. The cover plate 12 is detachably connected to the cavity 11 and covers the opening. The cover plate 12 is provided with positioning holes that correspond one-to-one with the spheres 21. The top of the spheres 21 extends out of the chassis 1 from the corresponding positioning holes.

[0041] The chassis 1 is divided into two independent components: a cavity 11 and a cover plate 12. The cavity 11 has an opening at the top, housing all the sensing modules 2. The cover plate 12 is detachably connected to the cavity 11 and covers the opening. This split structure facilitates pre-fixing and calibrating all sensing modules 2 within the cavity 11 during production assembly. During subsequent maintenance, the cover plate 12 can be directly removed to replace faulty modules without disassembling the entire chassis 1, significantly reducing the difficulty of equipment maintenance. The cover plate 12 has positioning holes corresponding to the spheres 21. The top of the spheres 21 extends out of the chassis 1 through the corresponding positioning holes. The positioning holes on the cover plate 12, together with the limiting holes on the lower limiting cover 23, form a double constraint, further limiting the swaying amplitude of the spheres 21 and ensuring that the rolling trajectory of the spheres 21 remains within a preset plane.

[0042] In some embodiments, there is a gap between the bottom edge of the circuit board 263 and the bottom surface of the cavity 11, so that the bottom of the circuit board 263 is completely suspended and ventilated. On the one hand, this prevents the dust and water accumulated on the surface of the chassis 1 from directly contacting the pins of the circuit board 263. On the other hand, air circulation can remove the small amount of heat generated by the circuit board 263 during operation, thus preventing the circuit board 263 from aging due to heat accumulation in a long-term sealed environment.

[0043] In some embodiments, the magnetic ring 261 and the Hall unit 26 are located completely below the limiting cover 23. The top edge of the limiting cover 23 extends upward to form a waterproof edge 232. The waterproof edge 232 is provided with at least one drain outlet 233. All drain outlets 233 are arranged in a staggered manner with the Hall unit 26 and the magnetic ring 261.

[0044] When beverages, sweat, or other liquids are accidentally spilled on the surface of the device, the liquid will only flow along the gaps in the cover plate 12 to the top of the limiting cover 23. Under the protection of the waterproof edge 232, it will not flow directly to the Hall unit 26 and magnetic ring 261 area below. The liquid will then be discharged from the side through the staggered drainage outlets 233. This achieves indirect waterproofing of the electronic component area from a structural perspective, completely avoiding the problem of short circuit and burnout caused by direct contact between liquid and the Hall unit 26 circuit board 263. This greatly improves the operational safety of the device in complex scenarios such as VR experience centers where there are dense crowds and users sweat a lot.

[0045] In some embodiments, the sensing module 2 further includes a locking bolt 29, with one locking bolt 29 provided on the side of each working shaft 24 away from the ball 21, and one locking bolt 29 provided on the side of the support shaft 25 away from the ball 21; the locking bolt 29 passes through the limit cover 23 and is threadedly connected to the bracket 22.

[0046] All three locking bolts 29 are arranged on the outer side away from the sphere 21. The three locking bolts 29 form a stable triangular fixing structure around the sphere 21, ensuring that the limiting cover 23 is evenly stressed around its perimeter, preventing localized warping and ensuring that the bottom of the limiting cover 23 can completely fit against the corresponding mounting surface of the bracket 22. Even under long-term upward force from the sphere 21, no localized deformation will occur. Simultaneously, this design of arranging the locking bolts 29 on the outer side completely avoids the movement area of ​​the sphere 21 within the bracket 22, preventing the bolt heads of the locking bolts 29 from interfering with the normal rolling of the sphere 21. During assembly and subsequent disassembly and maintenance, workers can directly tighten the bolts in the outer space without needing to reach into the confined space inside the bracket 22, significantly reducing the difficulty of disassembling and assembling the limiting cover 23. This significantly improves the efficiency of assembly and maintenance, and also facilitates subsequent cleaning and maintenance of the sphere 21 and shaft by opening the limiting cover 23 directly.

[0047] In some embodiments, the sensing module 2 has three drain outlets 233, each aligned with one of the three locking bolts 29, to prevent interference from the waterproof flange 232 on the tightening of the locking bolts 29. Furthermore, the three drain outlets 233 are evenly distributed along the triangular bolt positions, allowing liquid on the top surface of the limiting cover 23 to be simultaneously and quickly drained from the three drain outlets 233, preventing water accumulation at local corners within the waterproof flange 232. The drain outlets 233 directly drain liquid from the mounting positions of the locking bolts 29, preventing corrosion from prolonged immersion in water, extending the service life of the locking bolts 29, and preventing them from becoming stuck and impossible to disassemble and maintain.

[0048] In some embodiments, the sensing module 2 further includes a mounting bolt 210 and a limiting protrusion 212; the bottom of the bracket 22 is provided with a mounting through hole and a limiting through hole 221 that matches the shape of the limiting protrusion 212; the bottom end of the mounting bolt 210 passes through the mounting through hole and is threaded to the chassis 1; the limiting protrusion 212 is fixed to the chassis 1 and inserted into the limiting through hole 221.

[0049] By inserting the limiting protrusion 212 on the chassis 1 into the limiting through hole 221 at the bottom of the bracket 22, the bracket 22 is quickly and accurately positioned, ensuring that the installation angles of the two working rotating shafts 24 fully meet the design requirements and completely avoiding angular offset problems during assembly. Subsequently, only one mounting bolt 210 needs to be tightened to reliably position the bracket 22 in the fixed position on the chassis 1, ensuring the consistency of installation and assembly efficiency of all sensing modules 2. This positioning structure also prevents the bracket 22 from becoming loose or shifting when the device is subjected to lateral stepping force for a long time. Even if the user makes a large turning and pedaling motion, the bracket 22 can firmly remain in the initial preset position, and the fit between the rotating shaft and the ball 21 will not be disrupted due to bracket 22 shifting. The motion detection accuracy remains stable throughout long-term use.

[0050] In some embodiments, the edge of the limiting hole extends upward to form a limiting ring 231 that mates with the spherical surface of the sphere 21, and the top of the sphere 21 extends out of the limiting ring 231.

[0051] The edge of the limiting hole extends upward to form a limiting ring 231 that mates with the spherical surface of the sphere 21, with the top of the sphere 21 extending beyond the limiting ring 231. In traditional planar limiting holes, the edge of the limiting hole and the sphere 21 are in line contact. During the rolling process of the sphere 21, the edge of the limiting hole is prone to local wear. After long-term use, the effective diameter of the limiting hole will increase, and the swaying amplitude of the sphere 21 will increase accordingly. In severe cases, there may even be a safety hazard of the sphere 21 coming out of the hole. The inner ring of the limiting ring 231 of this structure is completely in contact with the spherical surface of the ball 21, greatly increasing the contact area and significantly reducing the compressive force per unit area. This not only significantly reduces the wear rate of the limiting structure and extends its service life, but also comprehensively constrains the radial sway of the ball 21, keeping it at the preset support height. This ensures that the contact pressure between the bottom of the ball 21 and the two working shafts 24 and one support shaft 25 below is always in the optimal state, preventing slippage due to the ball 21's up-and-down movement. This further improves the synchronization of the ball 21's rolling motion driving the shaft rotation and eliminates the problem of missed motion signal detection caused by the ball 21 slipping and spinning freely under extreme stress conditions.

[0052] In some embodiments, the outer wall of the bracket 22 is provided with a stiffening plate 211, and a wiring groove 2111 is provided on the stiffening plate 211.

[0053] The stiffening plates 211 on the outer side of the bracket 22 can significantly improve the overall structural strength of the bracket 22 and enhance its resistance to lateral compression. When the user's foot forcefully stomps on the ball 21, the bracket 22 will not bend or deform, ensuring that the relative positions of the three internal rotating shafts remain constant. This prevents the rotating shafts from getting stuck on the ball 21 and preventing it from rotating due to deformation of the bracket 22. The wiring grooves 2111 on the stiffening plates 211 can neatly store all the signal cables led out from the circuit board 263 of the Hall unit 26. All the cables will not be scattered inside the chassis 1, avoiding the risk of the cables being scratched and damaged by the rolling ball 21 and the rotating shafts. It also keeps the wiring inside the chassis 1 neat and orderly. During production assembly and subsequent maintenance and troubleshooting, the corresponding wiring of the sensing module 2 can be quickly identified, avoiding the problem of multiple sets of cables being tangled together and difficult to distinguish. This greatly improves the production assembly efficiency and the convenience of later maintenance of the equipment.

[0054] In some embodiments, the bottom surface of the chassis 1 is detachably connected to multiple support feet 3.

[0055] The bottom of the chassis 1 can be detachably connected to multiple support feet 3. This allows for flexible adjustment of the height of different support feet 3 according to the flatness of the ground, ensuring that the chassis 1 is level and preventing the ball 21 from rolling unnecessarily when stationary. It also allows for quick replacement of the support feet 3 after they wear out, without the need to move the entire chassis 1 to level it.

[0056] In some embodiments, a method for detecting foot movement speed and direction is also provided. When a user runs or walks on the simulation device for detecting foot movement speed and direction described in any of the above embodiments or any combination of embodiments, the balls drive the working shaft and the support shaft to rotate. The rotation speed of each ball is calculated separately, and the rotation speed includes direction and rate. Based on the rotation speed of all balls, the user's movement speed, including rate and direction, is calculated. The formula for calculating the speed V of the working shaft is as follows:

[0057] When the working shaft rotates, the two Hall sensors of the corresponding Hall unit will output two orthogonal square waves. When the phase difference between the two square waves is positive, the rotation direction of the working shaft is recorded as positive; when the phase difference between the two square waves is negative, the rotation direction of the working shaft is recorded as negative. r represents the radius of the working shaft, and T represents the period of the square wave. To calculate the rotational velocity vectors of the two working shafts and the rotational velocity of the ball, see [reference needed]. Figure 9 The horizontal axis Va represents the rotational speed of the working shaft perpendicular to the radial direction of the chassis, the vertical axis Vb represents the rotational speed of another working shaft, Vr represents the rotational speed of the ball, and α represents the rotational direction of the ball.

[0058] This method explicitly determines the rotation direction of a single working shaft directly by the positive or negative phase difference of orthogonal square waves, and provides a formula for calculating the working shaft speed. It abandons the complex process of relying on image processing to identify changes in the grayscale of the rolling ball surface, significantly improving computational efficiency. Even subtle foot movements such as slow walking or small turns can be quickly and accurately captured by the square wave signal output by the Hall sensor, easily identifying micron-level rolling displacements and reducing the possibility of missed detections. The method explicitly proposes using the vector sum of the rotational velocities of the two working shafts as the rotational velocity of a single rolling ball, and then further synthesizing the overall movement speed and direction of the user based on the rotational velocities of all the balls. This fully utilizes the sampling redundancy of the arrayed multi-sensor modules. Even if individual rolling balls fail to rotate due to momentary force, the data from the other normally collected balls can still achieve stable data fusion and output, greatly reducing the overall motion recognition deviation caused by single sensor anomalies. The entire detection method does not rely on optical path structure at all, eliminating the problems of missed steps and misjudgment caused by ball wear dust and environmental dust blocking the light path from the root. It greatly improves the reliability and accuracy of foot movement detection in VR interactive scenarios, and is fully adapted to the recognition needs of various complex actions such as precise turning and low-speed stealth in shooting VR games. It allows users to obtain smooth and lag-free virtual space movement feedback even in the limited chassis activity space.

[0059] Furthermore, methods for calculating the participant's movement speed based on the rotation speed of all spheres include, but are not limited to, vector synthesis, contact weighting, threshold filtering followed by fusion, and region weighting.

[0060] Vector synthesis method: First, acquire the output data of the two working axes of each ball to obtain two orthogonal motion components of a single ball in a two-dimensional plane. Perform a vector sum operation on the two components to obtain the complete rotational speed of a single ball, including speed and direction. Finally, directly perform algebraic summation on the motion vectors of all effective balls to obtain the total motion components and calculate the overall movement speed and direction of the user. This method is suitable for fast operation in low-computing-power embedded devices.

[0061] Contact Weighting Method: This method adds a contact state determination dimension to the vector synthesis logic. Based on the Hall signal output amplitude and continuous trigger duration of different rolling balls, it indirectly determines the actual contact force between the corresponding rolling ball and the user's foot, assigning a corresponding weight coefficient to each valid rolling ball. By multiplying the orthogonal motion components of each rolling ball by its own weight and then summing the results, invalid rolling ball data that is not actively touched by the foot or is only triggered by inertia can be filtered out. The final output of the user's motion result closely matches the actual movement trend of human body exertion, avoiding calculation deviations caused by meaningless local rolling.

[0062] Threshold-based fusion method: This method first sets a reasonable motion speed threshold to pre-filter out stationary or slightly jittery invalid rolling ball data with output rates below the threshold, eliminating interference signals caused by false triggers. After retaining all rolling ball data in a valid motion state, the average values ​​of the X-axis motion components and Y-axis motion components of all valid rolling balls are calculated separately. The two sets of average values ​​are then combined to obtain the final user movement vector. The calculation process is simple and stable, adaptable to VR scenarios with high traffic and multiple users, reducing computational load while ensuring the smoothness of the output results.

[0063] Region weighting method: This method combines the multi-layered array arrangement of sensing modules to divide the chassis into multiple independent detection areas, including the central ring area, the middle ring area, and the edge ring area. The rolling ball motion data in each area first completes vector fusion within the area to obtain the sub-region motion result. Then, based on the actual position of the user's center of gravity, the priority coefficient of the corresponding area is matched to complete the weighted synthesis of the data in the entire area. This method can adapt to non-uniform standing posture scenarios such as single-leg force and center of gravity shift, and avoids distortion in motion direction determination caused by insufficient sampling density in local areas.

[0064] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0065] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A simulation device for detecting the speed and direction of foot movement, characterized in that, It includes a chassis and multiple sensing modules arranged in an array within the chassis; the sensing modules include: a sphere, a bracket, a limit cover, a working shaft, a support shaft, and a Hall unit; The sphere is supported by two working shafts and one support shaft arranged in a triangle. Each working shaft is horizontal and rotatably connected to a bracket at both ends, and the support shaft is horizontal and connected to a bracket at both ends. The two working shafts are perpendicular to each other. Each working shaft corresponds to a Hall unit mounted on the bracket. The Hall unit includes a magnetic ring mounted on the end of the working shaft and two Hall sensors mounted on the bracket at the same distance from the magnetic ring. The sensing surfaces of the two Hall sensors are parallel to the working shafts and perpendicular to each other. A limiting cover is provided with a limiting hole with a diameter smaller than that of the sphere. The limiting cover is detachably connected to the bracket, and the top of the sphere extends out of the limiting hole from the limiting cover.

2. The simulation device for detecting foot movement speed and direction according to claim 1, characterized in that, The chassis is equipped with multiple sets of sensing modules along its own radial direction. Each set of sensing modules includes multiple sensing modules evenly distributed around the center of the chassis. Each sensing module has a working shaft perpendicular to the radial direction of the chassis.

3. The simulation device for detecting the speed and direction of foot movement according to claim 1 or 2, characterized in that, The sensing module also includes bearings; the two ends of the working shaft are connected to the bracket through two bearings, and the two ends of the support shaft are connected to the bracket through two bearings; neither the working shaft nor the support shaft makes frictional contact with the bracket and the limit cover.

4. The simulation device for detecting the speed and direction of foot movement according to claim 1 or 2, characterized in that, The chassis includes a cavity and a cover plate. The top of the cavity has an opening, and the sensing modules are all located inside the cavity. The cover plate is detachably connected to the cavity and covers the opening. The cover plate has positioning holes that correspond one-to-one with the spheres, and the top of the spheres protrudes from the chassis through the corresponding positioning holes. The Hall unit also includes a circuit board, and two Hall sensors are arranged on the circuit board. The two circuit boards are detachably connected to the outside of the bracket. There is a gap between the bottom edge of the circuit board and the bottom surface of the cavity.

5. The simulation device for detecting foot movement speed and direction according to claim 4, characterized in that, The magnetic ring and Hall unit are located completely below the limiting cover. The top edge of the limiting cover extends upward to form a waterproof edge. The waterproof edge is provided with at least one drain outlet. All drain outlets are staggered from the Hall unit and magnetic ring.

6. The simulation device for detecting the speed and direction of foot movement according to claim 5, characterized in that, The sensing module also includes locking bolts. Each working shaft has a locking bolt on the side away from the sphere, and the support shaft has a locking bolt on the side away from the sphere. The locking bolts pass through the limit cover threaded connection bracket. In the sensing module, there are three drain outlets, which are respectively aligned with the three locking bolts.

7. The simulation device for detecting the speed and direction of foot movement according to claim 1 or 2, characterized in that, The sensing module also includes mounting bolts and limiting protrusions; the bottom of the bracket is provided with mounting through holes and limiting through holes that match the shape of the limiting protrusions; the bottom end of the mounting bolt passes through the mounting through holes and is threaded to the chassis; the limiting protrusions are fixed to the chassis and inserted into the limiting through holes.

8. The simulation device for detecting the speed and direction of foot movement according to claim 1 or 2, characterized in that, The edge of the limiting hole extends upward to form a limiting ring that fits with the spherical surface of the sphere, and the top of the sphere extends out of the limiting ring.

9. The simulation device for detecting the speed and direction of foot movement according to claim 1 or 2, characterized in that, The outer wall of the support is equipped with stiffening plates, and wiring grooves are opened on the stiffening plates.

10. A method for detecting the speed and direction of foot movement, characterized in that, When a user runs or walks on the simulation device for detecting foot movement speed and direction as described in any one of claims 1-9, the balls drive the working shaft and the support shaft to rotate; the rotation speed of each ball is calculated, including direction and rate; the user's movement speed, including rate and direction, is calculated based on the rotation speed of all balls. The formula for calculating the speed V of the working shaft is as follows: When the working shaft rotates, the two Hall sensors of the corresponding Hall unit will output two orthogonal square waves. When the phase difference between the two square waves is positive, the rotation direction of the working shaft is recorded as positive; when the phase difference between the two square waves is negative, the rotation direction of the working shaft is recorded as negative. r represents the radius of the working shaft, and T represents the period of the square wave. Calculate the rotational velocity vectors of the two working shafts and the rotational velocity of the ball.

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