Active-passive combined force feedback glove

Abstract

The invention discloses an active and passive combined force feedback glove, which comprises a glove main body, an upper computer, a controller module, a brake group module and a transmission group module, and is characterized in that the controller module is arranged on the upper surface of the glove main body, and the controller module is in communication connection with the upper computer; the brake group module is arranged along the finger direction of the glove main body, and the brake group module is electrically connected with the controller module; the transmission group module is electrically connected with the controller module, the transmission group module is connected with the brake group module through a first cable, and the transmission group module drives the brake group module to move by controlling the length of the first cable. The MR brake of a conduit-rib structure is designed based on the shearing working mode of the magnetorheological fluid, the viscosity of the magnetorheological fluid is adjusted by changing the external magnetic field intensity in real time, the output force range, the response speed and the safety of the force feedback glove are improved, and therefore the interaction reality sense of a user is enhanced.

Description

Technical Field

[0001] The invention relates to the field of force-tactile human-computer interaction, and in particular to an active and passive combined force feedback glove. Background Art

[0002] In the fields of interactive virtual reality, augmented reality and remote control operations, such as medical simulation training, remote control of fine operations and advanced virtual reality games, the importance of force feedback devices has become increasingly prominent. Force feedback devices can provide physical tactile feedback, simulating the interaction of touch and force in the real world, thereby enhancing the user's sense of immersion and operational accuracy. Force feedback gloves are a common implementation method that can provide corresponding force feedback based on the interaction in the virtual environment or remote control operation.

[0003] In recent years, force feedback gloves are constantly being improved and developed. The wearing comfort, response speed and feedback accuracy of force feedback gloves directly affect the user experience. Traditional force feedback technology mainly relies on mechanical transmission devices such as motors and gears or piezoelectric materials to generate force feedback. Although these devices can simulate the feeling of force, they have some limitations. For example, the mechanical transmission system is usually complex and bulky in structure and cannot respond to the user's interactive actions in time, which greatly reduces the flexibility of the gloves and the comfort and safety of the user; for example, piezoelectric materials are limited by their limited deformation capacity, and the size and response speed of the feedback force generated cannot be well guaranteed. Therefore, it is very important to develop a force feedback glove and its force feedback solution with stable output response, comfortable wearing and accurate feedback. Summary of the invention

[0004] Purpose of the invention: In view of the above problems, the purpose of the present invention is to provide a force feedback glove that combines active and passive forces.

[0005] Technical solution: The active and passive combined force feedback glove of the present invention comprises a glove body, a host computer, a controller module, a brake group module and a transmission group module;

[0006] The controller module is arranged on the upper surface of the glove body, and the controller module is connected to the host computer for communication; the brake group module is arranged along the finger direction of the glove body, and the brake group module is electrically connected to the controller module; the transmission group module is applied to the wrist, and the transmission group module is electrically connected to the controller module, and the transmission group module is connected to the brake group module through a first cable, and the transmission group module drives the brake group module to move by controlling the length of the first cable;

[0007] The brake group module includes a coil. The surface of a second cable arranged inside the brake group module is covered with magnetorheological fluid. When the coil is energized, an external magnetic field is generated. Under the action of the external magnetic field, the magnetorheological fluid passes through a closed magnetic circuit. The controller module controls the current of the coil, thereby controlling the strength of the external magnetic field, and adjusts the viscosity of the magnetorheological fluid through the strength of the external magnetic field.

[0008] Further, the brake group module includes a PIP brake, an MCP brake, a hose, a fixing and a finger sleeve;

[0009] The PIP brake or the MCP brake is used as a brake unit, and two adjacent brake units are connected by a hose, which produces corresponding deformation as the finger joints are bent; the brake unit is fixed to the glove body through a fixing part, and the finger sleeve is arranged at the fingertip of the glove body, and the finger sleeve is connected to the brake unit through a third cable.

[0010] Further, the brake unit includes a second cable, a housing, a plug, a bobbin, a coil, and a seal;

[0011] The second cables in each brake unit are connected in sequence through steel wire ropes, and then connected to the first cable and the third cable to form one cable; the winding tube is a hollow column and is arranged on the outside of the second cable, and the sealing members are arranged at the two ends of the winding tube. A closed space is formed between the outer surface of the second cable, the inner surface of the winding tube and the inner side of the plug, and a magnetorheological fluid is arranged in the closed space, and the coil is wound on the outer surface of the winding tube; the outer shell is arranged at the outermost layer of the brake unit, the plug is in a circular ring shape, the plug is embedded in both ends of the outer shell, and the second cable passes through the plug and extends out of the brake unit; a small hole is arranged on the surface of the outer shell, and the coil passes through the small hole to be electrically connected to the controller module.

[0012] Furthermore, the transmission group module includes a wire box, a wristband, and a transmission group unit arranged inside the wire box, and two ends of the wristband are fixed to two sides of the wire box;

[0013] The transmission group unit includes a motor, a support frame, a frame, a gear set and a bobbin. The support frame and the frame are fixed inside the wire box, and the motor is fixed on the support frame; the gear set includes a driving gear, a first driven gear, a second driven gear, a third driven gear, a fourth driven gear and a fifth driven gear, the driving gear is meshed with the five driven gears respectively, the driving gear is connected to the transmission shaft of the motor, and the five driven gears are fixed on the frame through bearings; a bobbin is set at the center of the five driven gears, the end of the first cable is fixed on the bobbin and the first cable is wound on the bobbin; the five first cables pass through the holes set on the wire box and are respectively connected to the second cable in the brake unit on each finger.

[0014] Furthermore, the force feedback glove also includes a sensor module, a communication module and a power module. The communication module and the power module are arranged above the glove body, the sensor module is arranged on the finger sleeves of the glove body, the sensor module is communicatively connected to the controller module through the communication module, and the power module is electrically connected to the controller module.

[0015] Furthermore, the sensor module includes an angle sensor, a force sensor and a positioner.

[0016] Furthermore, the second cable, the plug and the shell are all made of electromagnetic pure iron, the first cable and the third cable are made of steel wire rope, and the winding tube is made of non-magnetic material.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0018] 1. The present invention designs a "duct-rib" structure MR brake based on the shear working mode of magnetorheological fluid. By changing the external magnetic field strength in real time to adjust the viscosity of the magnetorheological fluid, the output force range, response speed and safety of the force feedback glove are improved, thereby enhancing the user's interactive realism;

[0019] 2. The catheter-rib structure MR brake of the present invention has a simple structure, is easy to install and easy to control;

[0020] 3. The present invention adopts an under-driven motor-cable mechanism to realize the contraction of the cable, which improves the working efficiency of the brake and improves the portability and comfort of the gloves. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the overall structure of the active and passive combined force feedback glove;

[0022] Figure 2 It is a schematic diagram of the structure of the glove body;

[0023] Figure 3 It is a schematic diagram of the structure inside the brake unit;

[0024] Figure 4 It is a schematic diagram of the structure inside the transmission group module;

[0025] Figure 5 is a schematic diagram of the relative positions of the gear sets;

[0026] Figure 6 This is a block diagram of the hardware functional modules. DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0028] The active and passive combined force feedback gloves described in this embodiment are as follows: Figure 1 to Figure 2 As shown, the force feedback glove includes a glove body 1, a host computer, a controller module, a brake group module 2 and a transmission group module 3;

[0029] The controller module is arranged on the upper surface of the glove body 1, and the controller module is connected to the host computer by communication; the brake group module 2 is arranged along the finger direction of the glove body 1, and the brake group module 2 is electrically connected to the controller module; the transmission group module 3 is applied to the wrist, and the transmission group module 3 is electrically connected to the controller module, and the transmission group module 3 is connected to the brake group module 2 through a first cable, and the transmission group module 3 drives the brake group module 2 to move by controlling the length of the first cable;

[0030] The brake group module 2 includes a coil, and the surface of a second cable arranged inside the brake group module 2 is covered with magnetorheological fluid. When the coil is energized, an external magnetic field is generated, and the magnetorheological fluid is passed through a closed magnetic circuit under the action of the external magnetic field. The controller module controls the current of the coil, thereby controlling the strength of the external magnetic field, and adjusts the viscosity of the magnetorheological fluid through the strength of the external magnetic field.

[0031] In the force feedback glove of this embodiment, by real-time control of the external magnetic field applied by the brake group module 2 and by controlling the transmission group module 3, feedback force can be provided for the interaction between the five fingers and the virtual environment. By adjusting the viscosity of the magnetorheological fluid by changing the external magnetic field strength in real time, the output force range, response speed and safety of the force feedback glove are improved, and the user's interactive realism is enhanced.

[0032] Further, the brake group module includes a PIP (Proximal Interphalangeal) brake 25, a MCP (Metacarpophalangeal joint) brake 26, a hose 22, a fixing member 23 and a finger sleeve 24;

[0033] The PIP brake 25 or the MCP brake 26 is used as a brake unit 21, and two adjacent brake units 21 are connected by a hose 22. The hose 22 produces corresponding deformation as the finger joints are bent; the brake unit 21 is fixed to the glove body 1 through a fixing part 23, and the finger sleeves are arranged at the fingertips of the glove body 1. The finger sleeves 24 are connected to the brake unit 21 through a third cable. With the help of the finger sleeves 24, the user can better feel the force feedback of the fingertips.

[0034] The brake unit 21 is arranged between two joints, two brake units are arranged on the glove corresponding to the thumb, including one PIP brake 25 and one MCP brake 26, and three brake units are arranged on the gloves corresponding to the remaining fingers, including two PIP brakes 25 and one MCP brake 26. The difference between the PIP brake 25 and the MCP brake 26 is that they are different in length, and their internal structures are the same.

[0035] Furthermore, if Figure 3 As shown, the brake unit 21 includes a second cable 211, a housing 212, a plug 213, a bobbin 214, a coil 215 and a seal 217;

[0036] The second cables 211 of each brake unit 21 are connected in sequence by steel wire ropes, and then connected to the first cable and the third cable to form a cable; the bobbin 214 is a hollow column, arranged outside the second cable 211, and the seal 217 is arranged at the two ends of the bobbin 214. A closed space is formed between the outer surface of the second cable 211, the inner surface of the bobbin 214, and the inner side of the plug 213. A magnetorheological fluid 216 is arranged in the closed space, and the coil 215 is wound on the outer surface of the bobbin 214; the shell 212 is arranged at the outermost layer of the brake unit 21, the plug 213 is annular, the plug 213 is embedded in both ends of the shell 212, and the second cable 211 passes through the plug 213 and extends out of the brake unit 21; a small hole is arranged on the surface of the shell 212, and the coil 215 passes through the small hole to be electrically connected to the controller module. The brake unit constitutes a MR brake structure of a catheter-rib structure.

[0037] like Figure 3As shown, in one example, the cross-sectional radius of the second cable 211 is 2.4 mm, and it is made of electromagnetic pure iron DT4C with good magnetic conductivity. The second cable 211 can be contracted and stretched by the bending traction of the finger and the rotation of the spool 335 driven by the gear set 334 when working. The surface of the second cable 211 is covered by a layer of magnetorheological fluid 216, and the gap thickness of the magnetorheological fluid 216 is 0.3 mm. The thickness of the thin wall of the shell 212 is 1.8 mm, the length of the MCP brake 26 shell in the brake unit 21 corresponding to the thumb is 38 mm, and the length of the shell in the PIP brake 25 is 21 mm. The lengths of the remaining PIP brake 25 and MCP brake 26 shells 212 on the glove are 21 mm and 31 mm respectively. Fine holes are opened on the surface of the shell 212 to lead out the two ends of the coil 215 for electrical connection. The plug 213 is in the shape of a ring. Each brake unit 21 is provided with two plugs 213 stuck at both ends of the shell 212. The inner diameter of the plug 213 is adapted to the wire diameter of the second cable 211, and the outer diameter of the plug 213 is adapted to the inner diameter of the shell 212, and the thickness is 3mm. The plug 213 and the shell 212 are both made of electrical pure iron DT4C. Through the shell 212, the second cable 211 and the plug 213, the magnetorheological fluid 216 can be passed through the closed magnetic circuit under the action of the external magnetic field. The winding tube 214 is in the shape of a hollow column, with an outer diameter of 3mm on the bottom surface, and is made of non-magnetic conductive materials such as aluminum and platinum. The outer surface of the winding tube 214 is wound with a coil 215, and the cross-sectional radius of the coil 215 is 0.15mm. When the coil 215 is energized, an external magnetic field can be generated around it. The cross-sectional radius of the seal 217 is 6 mm and the thickness is 4 mm. It is made of a high-molecular plastic such as polytetrafluoroethylene PTFE that is resistant to high temperatures, has good density and a low friction coefficient. The seal 217 is arranged at both ends of the brake unit 21 and is fixedly connected to the housing 212 by bolts 219. A sealing ring 218 is provided inside it to prevent leakage of the magnetorheological fluid 216 during operation.

[0038] Furthermore, the transmission group module 3 includes a wire box 31, a wristband 32, and a transmission group unit arranged inside the wire box, and two ends of the wristband 32 are fixed on two sides of the wire box, and the transmission group module 3 is worn on the wrist of the user through the wristband 32;

[0039] like Figures 4 to 5As shown, the transmission group unit includes a motor 331, a support frame 332, a frame 333, a gear set 334 and a spool 335. The support frame 332 and the frame 333 are both fixed inside the wire box 31, and the motor 331 is fixed on the support frame 332 so that the motor 331 can operate stably; the gear set 334 includes a driving gear 3341, a first driven gear 3342, a second driven gear 3343, a third driven gear 3344, a fourth driven gear 3345 and a fifth driven gear 3346, the driving gear 3341 is meshed with the five driven gears respectively, the driving gear 3341 is connected to the transmission shaft of the motor 331, and the five driven gears are fixed on the frame through bearings; a bobbin 335 is set at the center of the five driven gears, the end of the first cable 210 is fixed on the bobbin 335 and the first cable 210 is wound on the bobbin 335; the five first cables 210 pass through the holes set in the wire box 31 and are respectively connected to the second cable 211 in the brake unit 2 on each finger.

[0040] A flat groove is provided on the transmission shaft of the motor 331, and the shape of the center hole of the driving gear 3341 is adapted to the shape of the end face of the transmission shaft of the motor 331, so as to stably transmit the torque to the gear set 334 through the driving gear 3341. The module and the number of teeth of the gear set 334 are designed and calculated to adapt to the lengths of different fingers, so that the gear set 334 can drive the stretching of each finger when working. The bobbin 335 is fixedly connected to its corresponding gear, and the internal structure of the bobbin 335 is spiral, with a bayonet in the center for fixing one end of the first cable 210, and a small hole with the same diameter as the first cable 210 on the surface. The under-driven motor-cable mechanism is used to achieve the contraction of the cable, which improves the working efficiency of the brake while improving the portability and comfort of the gloves.

[0041] Furthermore, if Figure 6 As shown in the hardware function module block diagram, the force feedback glove also includes a sensor module, a communication module 6 and a power module 7. Based on the sensor module, the original data of the virtual hand in the virtual space can be obtained. The communication module 6 is used to transmit data information between the host computer, the sensor module and the controller module 4, and the power module 7 is used to continuously supply power to the controller module 4. The communication module 6 and the power module 7 are arranged above the glove body 1, the sensor module is arranged on the finger sleeve of the glove body 1, the sensor module is connected to the controller module 4 through the communication module 6, and the power module 7 is electrically connected to the controller module 4. The controller module 4 receives the position information and angle information detected by the sensor module and controls the current size applied to the coil 215, thereby controlling the strength of the external magnetic field generated. The controller module 4 can receive the control instructions of the host computer based on the communication module 6, so that the motor 331 completes the power-on and power-off operations. The host computer is a PC, and the controller module is a minimum system development board based on STM32.

[0042] The sensor module includes an angle sensor 51, a force sensor 52 and a locator 53. The angle sensor 51 is used to measure the bending angle of the finger, the force sensor 52 is used to measure the force actively applied to the cable by the bending or stretching of the user's finger, and the locator 53 is used to detect the spatial position of the finger.

[0043] Furthermore, the second cable, the plug and the shell are all made of electromagnetic pure iron, the first cable and the third cable are made of steel wire rope, and the winding tube is made of non-magnetic material.

[0044] The following is the working process of the active and passive combined force feedback glove described in this embodiment:

[0045] The system is defined as the initial state before powering on. The upper computer performs software design to reconstruct the virtual object to be interacted with in the virtual environment. The locator 53 detects the spatial position information of the user's finger in real time and transmits it to the upper computer through the communication module 6. At this time, a virtual hand is generated in the virtual environment and reflects the user's finger posture and the relative position with the virtual object in real time. In the process of the user grasping and sensing the stiffness of the virtual object, the transmission group module 3 is always in the power-off state, and the first cable 210 is guided to extend the brake unit 21 as the user's finger bends.

[0046] When the virtual hand collides with the virtual object, the host computer sends a collision signal and transmits it to the controller module 4 through the communication module 6. The controller module 4 adjusts the current applied to the coil 214 of the brake unit 21 according to the virtual object stiffness preset by the system and continuously supplies power, thereby changing the viscosity of the magnetorheological fluid 216 and generating a damping force of the expected magnitude. The first cable 210 transmits the damping force to the fingertips to achieve a corresponding force feedback effect. The user can intuitively feel the stiffness of the virtual object through the force feedback glove of the present invention.

[0047] When the force sensor 52 detects the tensile force actively applied to the first cable 210 by the user's finger, and the user's finger posture detected by the angle sensor 51 reaches the preset condition, the host computer issues a power-off command, the controller module 4 stops supplying power to the brake group module 2, and the brake unit 21 will quickly stop generating damping force; at the same time, the host computer issues a stretching command, the controller module 4 receives the command to control the motor 331 to operate, and the active gear 3341 drives the five driven gears to work under the operation of the motor 331, thereby controlling the spool 335 to rotate and retract the cable 211; when the angle sensor 51 detects the initial finger angle, the host computer issues a power-off command, and the system returns to the initial working state.

Claims

1. An active and passive combined force feedback glove, characterized in that: It includes a glove body, a host computer, a controller module, a brake group module and a transmission group module; The controller module is arranged on the upper surface of the glove body, and the controller module is connected to the host computer for communication; the brake group module is arranged along the finger direction of the glove body, and the brake group module is electrically connected to the controller module; the transmission group module is applied to the wrist, and the transmission group module is electrically connected to the controller module, and the transmission group module is connected to the brake group module through a first cable, and the transmission group module drives the brake group module to move by controlling the length of the first cable; The brake group module includes a coil, which generates an external magnetic field when energized. The surface of a second cable arranged inside the brake group module is covered with magnetorheological fluid. The magnetorheological fluid is passed through a closed magnetic circuit under the action of the external magnetic field. The controller module controls the current passed into the coil, thereby controlling the strength of the external magnetic field, and adjusts the viscosity of the magnetorheological fluid through the strength of the external magnetic field.

2. The active and passive combined force feedback glove according to claim 1, characterized in that: The brake group module includes PIP brake, MCP brake, hose, fixings and finger sleeves; The PIP brake or the MCP brake is used as a brake unit, and two adjacent brake units are connected by a hose, which produces corresponding deformation as the finger joints are bent; the brake unit is fixed to the glove body through a fixing part, and the finger sleeve is arranged at the fingertip of the glove body, and the finger sleeve is connected to the brake unit through a third cable.

3. The active and passive combined force feedback glove according to claim 2, characterized in that: The brake unit includes a second cable, a housing, a plug, a bobbin, a coil, and a seal; The second cables in each brake unit are connected in sequence through a steel wire rope, and then connected with the first cable and the third cable to form one cable; The winding tube is a hollow column and is arranged on the outside of the second cable. The sealing members are arranged at the two ends of the winding tube. A closed space is formed between the outer surface of the second cable, the inner surface of the winding tube and the inner side of the plug. Magnetorheological fluid is arranged in the closed space, and the coil is wound on the outer surface of the winding tube. The outer shell is arranged on the outermost layer of the brake unit, the plug is in a circular ring shape, the plug is embedded in both ends of the outer shell, and the second cable passes through the plug and extends out of the brake unit. Small holes are arranged on the surface of the outer shell, and the coil is electrically connected to the controller module through the small holes.

4. The active and passive combined force feedback glove according to claim 3, characterized in that: The transmission group module includes a wire box, a wristband, and a transmission group unit arranged inside the wire box, and two ends of the wristband are fixed on both sides of the wire box; The transmission group unit includes a motor, a support frame, a frame, a gear set and a bobbin. The support frame and the frame are fixed inside the wire box, and the motor is fixed on the support frame; the gear set includes a driving gear, a first driven gear, a second driven gear, a third driven gear, a fourth driven gear and a fifth driven gear, the driving gear is meshed with the five driven gears respectively, the driving gear is connected to the transmission shaft of the motor, and the five driven gears are fixed on the frame through bearings; a bobbin is set at the center of the five driven gears, the end of the first cable is fixed on the bobbin and the first cable is wound on the bobbin; the five first cables pass through the holes set on the wire box and are respectively connected to the second cable in the brake unit on each finger.

5. The active and passive combined force feedback glove according to claim 4, characterized in that: It also includes a sensor module, a communication module and a power module. The communication module and the power module are arranged above the glove body, the sensor module is arranged on the finger sleeves of the glove body, the sensor module is communicatively connected with the controller module through the communication module, and the power module is electrically connected with the controller module.

6. The active and passive combined force feedback glove according to claim 5, characterized in that: The sensor module includes an angle sensor, a force sensor and a positioner.

7. The active and passive combined force feedback glove according to claim 6, characterized in that: The second cable, the plug and the shell are all made of electromagnetic pure iron, the first cable and the third cable are made of steel wire rope, and the winding tube is made of non-magnetic material.

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