Hand joint motion capture device

Abstract

The invention discloses a hand joint motion capture device, comprising a hand surface fixing block (1), five finger assemblies, each of the finger assemblies comprising at least one finger joint (2), each adjacent finger joint (2) and the finger joint (2) and the hand surface fixing block (1) are hinged via a hinged connector (3), each of the hinged connectors (3) is provided with an angle sensor (4), and the five finger assemblies and the hand surface fixing block (1) are respectively arranged at a ratio of 1:1 to the human palm. The angle sensor is used to directly capture the bending angle of the joint in real time and continuously at a ratio of 1:1, with high capture accuracy, while taking into account low cost, simple operation, and low environmental requirements.

Description

Technical Field

[0001] The invention relates to the field of human hand joint motion capture, and in particular to a hand joint motion capture device. Background Art

[0002] According to the working principle of motion capture, it can be roughly divided into two categories: field-assisted type and independent wearable type. Acoustic motion capture, electromagnetic motion capture, and optical motion capture belong to field-assisted type; independent wearable type is divided into inertial sensor type, bending sensor type, and angle sensor type according to different sensors.

[0003] The field-assisted type requires a high-precision fixed physical field or geometric space base point as a reference point for motion capture for measurement, and a high-speed computer for calculation and degree of freedom analysis. Therefore, the equipment is relatively large and the cost is relatively high. It can only be used in high-value-added projects and cannot be used by ordinary workers, especially in high-risk and harsh environments and where the users have low educational qualifications.

[0004] The inertial sensor type uses an inertial navigation sensor. Due to the size and weight of the human body, as well as the large number of degrees of freedom to be collected, a high-precision gyroscope with a certain size and weight cannot be used (high-precision gyroscopes are particularly expensive). The accumulated error over time will cause the collection accuracy to be insufficient. This is acceptable for a short period of time, but it is not suitable for long-term production labor.

[0005] The bending sensor type uses a resistive or optical fiber bending sensor. Although the capture mechanism using this type of sensor is light and wearable, the bending sensor has poor accuracy and is relatively expensive.

[0006] The existing capture mechanism using angle sensors can also be called a mechanical exoskeleton capture mechanism. It adopts a joint-link structure. Because its sensor cannot directly measure the rotation angle of the joint, it needs to calculate the key point rotation angle based on the size and position of the mechanism. Although real-time measurement can be achieved, due to the different hand sizes of different people, or the different wearing positions of the same person, there will be errors in the calculation results, and the repeatability of the measurement results is poor. Summary of the invention

[0007] In order to overcome the above shortcomings, the purpose of the present invention is to provide a hand joint motion capture device, which uses an angle sensor to directly capture the bending angle of the joint in real time and continuously at a 1:1 ratio, with high capture accuracy, while taking into account low cost, easy operation and low environmental requirements.

[0008] In order to achieve the above purpose, the technical solution adopted by the present invention is: a hand joint motion capture device, including a hand surface fixing block and five finger assemblies, each of the finger assemblies includes at least one finger joint, and each two adjacent finger joints and the finger joints and the hand surface fixing block are hinged by hinged connectors, each of the hinged connectors is provided with an angle sensor, and the five finger assemblies and the hand surface fixing block are respectively set at a 1:1 ratio with the human palm.

[0009] The beneficial effect of the hand joint motion capture device of the present invention is that it studies the movement law of hand bones, uses bionics principles, adopts a mechanical exoskeleton wearable structure, and uses an angle sensor to directly capture the bending angle of the joint in real time and continuously at a 1:1 ratio, with high capture accuracy, while taking into account low cost, easy operation, and low environmental requirements.

[0010] As a further improvement of the present invention, each of the knuckles includes a knuckle fixing block, at least one finger slider and an elastic limit reset part, the knuckle fixing block is provided with a slide rail, the at least one finger slider is slidably provided on the slide rail of the knuckle fixing block, and the elastic limit reset part forces the finger slider to reset to the initial position of the slide rail through elastic force; and when at least two finger sliders are provided, the elastic limit reset part limits the distance between each two adjacent finger sliders. The setting of the slide rail and the finger slider allows the finger slider to move forward and backward on the slide rail, and the setting of the elastic limit reset part provides the hand slider with the function of limiting and resetting, so that the hand joint motion capture device can be adjusted according to different hand sizes and is compatible with different sizes.

[0011] Preferably, each of the elastic limit reset parts adopts a compression spring, and the compression spring is located on one side of the finger slider, or between two finger sliders. The limit and reset functions of the finger slider can be realized, the structure is simple, the assembly is convenient, and the cost is saved. Generally, the compression spring is located on one side of the finger slider for the knuckle at the free end of each finger assembly, and the compression spring is located between the two finger sliders for the knuckle in the middle of the finger assembly.

[0012] Preferably, each of the articulated connectors includes a first joint component and a second joint component that are rotatably connected, and the outer end surfaces of the first joint component and the second joint component are fixed with a finger guide shaft, and the finger guide shaft passes through the adjacent hand surface fixing block or finger slider, and the compression spring is sleeved on the finger guide shaft, and the end of the finger guide shaft is provided with a limit block to prevent the compression spring from moving outward. The matching arrangement of the finger guide shaft and the compression spring makes the assembly of the compression spring simple.

[0013] Preferably, the first joint has a convex block, and the same end face of the second joint is provided with two slots, the convex block is inserted into one of the slots, the angle sensor is inserted into the other slot, an inner ring with a D-shaped hole is provided in the angle sensor, and a sensor shaft is provided on the second joint, and the sensor shaft passes through the first joint, the second joint and the inner ring with the D-shaped hole. When the finger joint moves, the first joint and the second joint can be driven to move, that is, the sensor shaft and the angle sensor produce relative motion, and the motion angle is consistent with the motion angle of the finger joint, so as to directly capture the motion angle of the finger assembly.

[0014] Preferably, one of the five finger assemblies is a thumb finger assembly, and the thumb finger assembly is rotatably connected to the palm fixed block through a thumb cavity palm joint swing capture mechanism, and the thumb cavity palm joint swing capture mechanism includes two articulated connectors, namely a first thumb articulated connector and a second thumb articulated connector, wherein the first thumb articulated joint of the first thumb articulated connector is fixed to the palm fixed block, and a thumb swing shaft is rotatably provided on the third thumb articulated joint of the second thumb articulated connector, and the thumb swing shaft slides through the second thumb articulated joint of the first thumb articulated connector and is fixedly sleeved with a reset compression spring, and the fourth thumb articulated joint of the second thumb articulated connector is slidably connected to the first joint of the articulated connector of the thumb finger assembly. Due to the above-mentioned articulated connector adopted by the thumb cavity palm joint swing capture mechanism, an angle sensor is also provided on the articulated connector, and when the thumb moves, the relevant parts can be driven to move, so as to capture the opening and closing angle of the thumb relative to the palm surface and the tilting angle of the thumb surface relative to the palm surface in real time.

[0015] Preferably, the lower end surface of the knuckle fixing block is an arc-shaped structure, which better fits the back of the user's finger. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional diagram of this embodiment;

[0017] Figure 2 It is a three-dimensional diagram of two finger joints connected by a hinged connection member in this embodiment;

[0018] Figure 3 is a three-dimensional diagram of the second joint component in this embodiment;

[0019] Figure 4 3D is a stereoscopic diagram of the angle sensor and the sensor axis in this embodiment. DETAILED DESCRIPTION

[0020] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0021] See attached Figure 1 As shown in FIG. 4 , a hand joint motion capture device of this embodiment includes a hand surface fixed block 1, five finger assemblies, namely thumb finger assembly S1, index finger assembly S2, middle finger assembly S3, ring finger assembly S4, and pinky finger assembly S5. Among them, thumb finger assembly S1 and pinky finger assembly S5 each include one knuckle 2, and index finger assembly S2, middle finger assembly S3, and ring finger assembly S4 each include two knuckles 2. The knuckles 2 of thumb finger assembly S1 and pinky finger assembly S5 are hinged to the hand surface fixed block 1 through an articulated connector 3, and one knuckle 2 of index finger assembly S2, middle finger assembly S3, and ring finger assembly S4 near the hand surface fixed block 1 is hinged to the hand surface fixed block 1 through an articulated connector 3; the two knuckles 2 are hinged to each other through an articulated connector 3. An angle sensor 4 is provided on each articulated connection part 3, and the five finger assemblies (thumb finger assembly S1, index finger finger assembly S2, middle finger finger assembly S3, ring finger finger assembly S4, little finger finger assembly S5) and the palm fixing block 1 are respectively arranged in a 1:1 ratio with the human palm.

[0022] In this embodiment, each knuckle 2 includes a knuckle fixing block 21, at least one finger slider 22, and an elastic limit reset portion 23. The knuckles 2 of the thumb finger assembly S1, the pinky finger assembly S5, and the knuckles 2 at the end of the index finger assembly S2, the middle finger assembly S3, and the ring finger assembly S4 all include a finger slider 22, and the other knuckles 2 of the index finger assembly S2, the middle finger assembly S3, and the ring finger assembly S4 all include two finger sliders 22. The upper end surface of the knuckle fixing block 21 is provided with a slide rail 24, and at least one finger slider 22 is slidably provided on the slide rail 24 of the knuckle fixing block 21, wherein the lower end surface of the knuckle fixing block 21 is an arc-shaped structure, and the elastic limit reset portion 23 forces the finger slider 22 to reset to the initial position of the slide rail 24 through elastic force. Each elastic limit reset part 23 adopts a compression spring, which is arranged on the outside of the finger slider 22 at the end of the knuckle 2 of the thumb finger assembly S1, the little finger finger assembly S5, and the end of the knuckle 2 of the index finger finger assembly S2, the middle finger finger assembly S3, and the ring finger finger assembly S4, and is arranged between the two finger sliders 22 of the other knuckle 2 of the index finger finger assembly S2, the middle finger finger assembly S3, and the ring finger finger assembly S4.

[0023] Specifically, each articulated connection part 3 includes a first joint part 31 and a second joint part 32 which are rotatably connected. A finger guide shaft 33 is fixed to the outer end faces of the first joint part 31 and the second joint part 32. The finger guide shaft 33 passes through the adjacent hand fixing block 1 or the adjacent finger slider 22. The compression spring is sleeved on the finger guide shaft 33. The end of the finger guide shaft 33 is provided with a limit block 34 to prevent the compression spring from moving outward.

[0024] In this embodiment, the first joint component 31 and the second joint component 32 are connected in rotation by the following structure: the first joint component 31 has a protrusion 35, so that the cross section of the first joint component 31 is in the shape of a "T", and the same end face of the second joint component 32 is provided with two slots 36, so that the cross section of the second joint component 32 is in the shape of a "mountain", the protrusion 35 is inserted into one of the slots 36, and the angle sensor 4 is inserted into the other slot 36, and the angle sensor 4 is provided with an inner ring with a D-shaped hole 37, and the second joint component 32 is provided with a sensor shaft 38, and the sensor shaft 38 passes through the first joint component 31, the second joint component 32 and the inner ring with the D-shaped hole 37. When the finger joint 2 moves, it can drive the first joint component 31 and the second joint component 32 to move, that is, the sensor shaft 38 and the angle sensor produce relative motion, and the action angle is consistent with the action angle of the finger joint, so as to directly capture the action angle of the finger assembly.

[0025] The thumb-finger assembly S1 in this embodiment is rotatably connected to the palm fixing block 1 through the thumb cavity palm joint swing capture mechanism 5. The thumb cavity palm joint swing capture mechanism 5 includes two articulated connectors 3, namely a first thumb articulated connector 51 and a second thumb articulated connector 52. The structures of the first thumb articulated connector 51 and the second thumb articulated connector 52 are consistent with the structures of the articulated connector 3. Similarly, the first thumb articulated connector 51 and the second thumb articulated connector 52 also have an angle sensor 4, and the installation structure of the angle sensor 4 is consistent with the above structure. The first thumb articulated joint 51a of the first thumb articulated connecting member 51 is fixed on the palm fixing block 1, and a thumb swing shaft 53 is rotatably arranged on the third thumb articulated joint 52a of the second thumb articulated connecting member 52. The thumb swing shaft 53 slides through the second thumb articulated joint 51b of the first thumb articulated connecting member 51 and is fixedly sleeved with a reset compression spring 54. The fourth thumb articulated joint 52b of the second thumb articulated connecting member 52 is slidably connected to the first joint 31 of the articulated connecting member 3 of the thumb finger assembly S1.

[0026] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A hand joint motion capture device, comprising a hand surface fixing block (1), five finger assemblies, each of the finger assemblies comprising at least one knuckle (2), characterized in that: Each of the two adjacent finger joints (2) and the finger joints (2) and the palm fixing block (1) are hingedly connected via hinged connectors (3), each of the hinged connectors (3) is provided with an angle sensor (4), and the five finger assemblies and the palm fixing block (1) are respectively arranged in a 1:1 ratio with the human palm; Each of the knuckles (2) comprises a knuckle fixing block (21), at least one finger slider (22) and an elastic limit reset portion (23); a slide rail (24) is arranged on the knuckle fixing block (21); the at least one finger slider (22) is slidably arranged on the slide rail (24) of the knuckle fixing block (21); and the elastic limit reset portion (23) forces the finger slider (22) to reset to the initial position of the slide rail (24) through elastic force; Each of the elastic limit reset parts (23) adopts a compression spring, and the compression spring is located on one side of the finger slider (22), or between two finger sliders (22).

2. The hand joint motion capture device according to claim 1, characterized in that: Each of the articulated connecting parts (3) comprises a first joint part (31) and a second joint part (32) which are rotatably connected, and the outer end faces of the first joint part (31) and the second joint part (32) are fixed with a finger guide shaft (33), and the finger guide shaft (33) passes through the adjacent hand surface fixing block (1) or finger slider (22), and the compression spring is sleeved on the finger guide shaft (33), and the end of the finger guide shaft (33) is provided with a limit block (34) for preventing the compression spring from moving outward.

3. The hand joint motion capture device according to claim 2, characterized in that: The first joint component (31) has a convex block (35); the same end surface of the second joint component (32) is provided with two slots (36); the convex block (35) is inserted into one of the slots (36); the angle sensor (4) is inserted into the other slot (36); an inner ring with a D-shaped hole (37) is provided in the angle sensor (4); a sensor shaft (38) is passed through the first joint component (31), the second joint component (32) and the inner ring with the D-shaped hole (37).

4. The hand joint motion capture device according to claim 1, characterized in that: One of the five finger assemblies is a thumb finger assembly (S1), and the thumb finger assembly (S1) is rotatably connected to the palm fixing block (1) via a thumb cavity palm joint swing capture mechanism (5) and the thumb finger assembly (S1), and the thumb cavity palm joint swing capture mechanism (5) comprises two articulated connectors (3), namely a first thumb articulated connector (51) and a second thumb articulated connector (52), wherein a first thumb articulated joint component (51a) of the first thumb articulated connector (51) is fixed On the palm fixing block (1), a thumb swing shaft (53) is rotatably arranged on the third thumb articulated joint (52a) of the second thumb articulated connection member (52), the thumb swing shaft (53) slides through the second thumb articulated joint (51b) of the first thumb articulated connection member (51) and is fixedly sleeved with a return compression spring (54), and the fourth thumb articulated joint (52b) of the second thumb articulated connection member (52) is slidably connected to the first joint (31) of the articulated connection member (3) of the thumb finger assembly (S1).

5. The hand joint motion capture device according to claim 1, characterized in that: The lower end surface of the knuckle fixing block (21) is an arc-shaped structure.

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