A rigid-flexible switching series elastic actuator

Abstract

The present invention discloses a rigid-flexible switching series elastic driver, comprising a support protection module, an external input module, a load driving module, and a rigid-flexible switching module; wherein the support protection module is used to install the external input module, the load driving module, and the rigid-flexible switching module; the external input module is connected to the first connection part through a joint ball bearing I, and the force of the first connection part is transmitted to the spring I in the external input module; the load driving module is connected to the second connection part through a joint ball bearing II, and the second connection part is driven by the drive motor to provide an output torque; the rigid-flexible switching module completes the locking and loosening of the spring I under the drive of the reduction motor. The present invention has a compact structure; realizes the switching between the rigid mode and the flexible mode, can meet the two different use requirements of providing waist assistance and waist support for the wearer, and further provides emergency protection for the wearer, effectively avoiding the wearer from being injured again during recovery training.

Description

Technical Field

[0001] The invention relates to a rigid-flexible switching series elastic driver, belonging to the technical field of robots. Background Art

[0002] A survey on the degree of physical fatigue of people who have been engaged in heavy physical labor for a long time shows that waist pain is the most serious problem. 67% of the medical personnel claim that they suffer from waist pain, and the proportion in the automobile manufacturing industry is 84%. In addition, the aging process is gradually accelerating, and the number of elderly hemiplegic patients who cannot sit up normally is increasing year by year. For hemiplegic patients, sit-up training can promote the improvement of patients' limb function and improve their quality of life. Clinical studies have found that the waist-assisted exoskeleton robot can be used to make up for the problem of insufficient muscle strength of elderly patients and help them to do sit-up training.

[0003] At present, the waist rehabilitation assisting exoskeleton robots on the market use motors as the torque output source. The output torque needs to be converted through a specific mechanical structure to become the assisting force required for waist movement. It has strong rigidity. At the same time, this driving method can provide sufficient output torque to achieve assisting force during operation, but it cannot achieve support for the waist under specific conditions. It cannot simultaneously meet the dual needs of flexible assisting force and rigid support required by patients when using it, which affects the overall effectiveness of rehabilitation training. Therefore, it is very necessary to have a driver that has both high flexibility and can quickly switch between flexible mode and rigid mode. The series elastic driver is a good choice.

[0004] At present, some waist rehabilitation exoskeleton robots on the market use serial elastic actuators to assist waist rehabilitation, but the above technical solutions have the following technical defects:

[0005] 1. Currently, most of the serial elastic actuators suitable for waist-assisted exoskeletons can only be driven flexibly, and cannot meet the needs of switching to rigid mode in time when the wearer needs support;

[0006] 2. Currently, most of the series elastic actuators suitable for waist-assisted exoskeletons are unable to quickly lock the device to protect the wearer when the waist is suddenly subjected to a large force during operation, which greatly increases the risk of rehabilitation treatment for the wearer. Summary of the invention

[0007] The invention provides a rigid-flexible switching series elastic driver, which can realize rigid-flexible mode switching.

[0008] The technical solution of the present invention is: a rigid-flexible switching series elastic driver, comprising a support protection module 1, an external input module 2, a load driving module 3, and a rigid-flexible switching module 4; wherein the support protection module 1 is used to install the external input module 2, the load driving module 3, and the rigid-flexible switching module 4; the external input module 2 is connected to the first connection part through a joint ball bearing I21, and the force of the first connection part is transmitted to the spring I14 in the external input module 2; the load driving module 3 is connected to the second connection part through a joint ball bearing II38, and the output torque is provided by the drive motor 25 to drive the second connection part; the rigid-flexible switching module 4 completes the locking and loosening of the spring I14 under the drive of the reduction motor 46, thereby realizing the switching between the rigid mode and the flexible mode.

[0009] The axial direction of the joint ball bearing I21 is parallel to the axial direction of the joint ball bearing II38, and both are located on opposite sides of the support protection module 1.

[0010] The support and protection module 1 includes a series elastic driver housing I5, a support frame 7, and a series elastic driver housing II8; wherein the series elastic driver housing I5 is connected to the series elastic driver housing II8 and the support frame 7 is installed between the two.

[0011] The external input module 2 includes a spring I14, a spring limiting slider 15, a double-headed screw 18, a rack-like mechanism I19, and a joint ball bearing I21; wherein, one end of the joint ball bearing I21 is connected to the first connecting part, the other end of the joint ball bearing I21 is fixed to one end of the double-headed screw 18, the other end of the double-headed screw 18 is connected to one end of the spring limiting slider 15, one end of the spring I14 is sleeved on the other end of the spring limiting slider 15, and the other end of the spring I14 is limited in the axial direction by the support frame 7 in the support protection module 1; the spring limiting slider 15 is slidably matched with the support frame 7; a rack-like mechanism I19 is installed on the double-headed screw 18, and the engagement and non-engagement of the rack-like mechanism II60 and the rack-like mechanism I19 in the rigid-flexible switching module 4 are realized by driving the rigid-flexible switching module 4.

[0012] The spring I14, the spring limiting slider 15, and the double-headed screw 18 are radially limited by the space formed by the support frame 7 and the elastic driver housing I5 in series in the support protection module 1.

[0013] The load driving module 3 includes a driving motor 25, a gear I26, a gear II31, a deep groove ball bearing 32, a screw 35, a screw nut 36, an internal threaded tube 37, and a joint ball bearing II38; wherein the driving motor 25 is fixed on the load support frame 7 in the support protection module 1, the gear I26 is fixed on the output shaft of the driving motor 25, the gear I26 is meshed with the gear II31 for transmission, the gear II31 is fixed to the top of the screw 35, the deep groove ball bearing 32 is fixed on the screw 35, the screw nut 36 is meshed with the screw 35 for transmission, one end of the internal threaded tube 37 is fixedly connected to the screw nut 36, and the other end of the internal threaded tube 37 passes through the internal threaded tube limiting hole 39 in the load support frame 7 and is fixedly connected to the joint ball bearing II38, and the joint ball bearing II38 is connected to the second connecting part to convert the output torque of the driving motor into a driving torque to drive the second connecting part.

[0014] The rigid-flexible switching module is powered by a reduction motor 46, and the rotation of the reduction motor 46 drives the rotation of gear III44, which meshes with gear IV51. The rotation of gear IV51 drives the rotation of the cam link 54, and the cam link boss 55 at one end of the cam link 54 slides in the cam groove 63 in the cam 58, converting the rotation of the cam link 54 into the up and down movement of the cam 58 along the axial direction, and the rack-like mechanism II60 moves with the cam 58, and the up and down movement of the rack-like mechanism II60 realizes the engagement and non-engagement with the rack-like mechanism I19.

[0015] The rigid-flexible switching module includes a gear III44, a reduction motor 46, a gear IV51, a cam limit fixing nut 52, a cam connecting rod 54, a cam connecting rod boss 55, a cam 58, a spring II59, a rack-like mechanism II60, a cam mechanism base 61, and a cam slide 63; wherein the reduction motor 46 and the cam mechanism base 61 are fixed to the outer side of the series elastic driver housing I5 in the support protection module 1, the gear III44 fixed on the output shaft of the reduction motor 46 is meshed with the gear IV51, and the gear IV51 is fixed to the cam connecting rod 5 On the top rotating shaft, the cam link boss 55 at the other end of the cam link 54 cooperates with the cam slide groove 63 in the cam 58; the spring II59 is sleeved on the cam 58, and the spring II59 and the cam 58 are placed in the cylindrical hole of the cam mechanism base 61 as a whole, and the cam limit fixing nut 52 sleeved on the cam link 54 is fixedly connected to one end of the cam mechanism base 61; the rack-like mechanism II60 is fixed to one end of the cam 58 and extends from the other end of the cam mechanism base 61, and the rack-like mechanism II60 is meshed with the rack-like mechanism I19 to lock the spring I14.

[0016] The other end of the cam 58 is fixed with a cross fixing piece 57 , and the lower end surface of the cross fixing piece 57 is tangent to the surface of the cam sliding groove 63 .

[0017] The beneficial effects of the present invention are as follows: the three main modules of the present invention are installed through the supporting and protecting module, and the structure of the whole device is compact; the external input module, the load driving module, and the rigid-flexible switching module realize the switching between the rigid mode and the flexible mode through ingenious cooperation; by realizing the switching between the two modes, it can meet the two different usage requirements of providing the wearer with waist assistance and waist support, and further provide emergency protection for the wearer, effectively avoiding the wearer from secondary injury during recovery training. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the overall structure diagram of the present invention;

[0019] Figure 2 Schematic diagram of disassembly of the support and protection module of the present invention Figure 1 ;

[0020] Figure 3 Schematic diagram of disassembly of the support and protection module of the present invention Figure 2 ;

[0021] Figure 4 This is a schematic diagram of the overall assembly of the external input module of the present invention;

[0022] Figure 5 This is a schematic diagram of disassembling the external input module of the present invention;

[0023] Figure 6 A schematic diagram showing the overall assembly of the load drive module of the present invention from multiple perspectives;

[0024] Figure 7 This is a schematic diagram of disassembling the load driving module of the present invention;

[0025] Figure 8 This is a schematic diagram of the assembly of the rigid-flexible switching module of the present invention;

[0026] Fig. 9 This is a schematic diagram of the overall disassembly of the rigid-flexible switching module of the present invention;

[0027] Fig.10 This is a schematic diagram of the disassembly of the reduction motor of the present invention;

[0028] Fig.11 This is a schematic diagram of the encoder disassembly of the present invention;

[0029] Fig.12 This is a disassembly diagram of the rotary-to-linear mechanism of the present invention;

[0030] Fig.13 This is a schematic half-section diagram of a partial assembly of a rigid-flexible switching module of the present invention;

[0031] Fig.14 It is a schematic diagram of the boss and the cross fixing member of the present invention;

[0032] Fig.15 It is a top view schematic diagram of the cam and the cross fixing member of the present invention;

[0033] Fig.16 This is a schematic diagram of a power distribution box of the present invention;

[0034] The numbers in the figure are: 1-support protection module, 2-external input module, 3-load drive module, 4-rigid-flexible switching module, 5-series elastic driver housing I, 6-series elastic driver housing I boss, 7-support frame, 8-series elastic driver housing II, 9-spring I limiting boss I, 10-double-headed screw fixing groove I, 11-series elastic driver housing II groove, 12-screw I, 13-screw II, 14-spring I, 15-spring limiting slider, 16-spring limiting slider limiting groove , 17-displacement sensor I, 18-double-headed screw, 19-type rack mechanism I, 20-double-headed screw fixing groove II, 21-joint ball bearing I, 22-spring I limiting boss II, 23-spring I limiting groove, 24-spring limiting slider limiting boss, 25-drive motor, 26-gear I, 27-gear top screw, 28-screw III, 29-deep groove ball bearing fixing groove I, 30-displacement sensor II, 31-gear II, 32-deep groove ball bearing, 33-deep groove ball bearing fixing groove I I, 34-screw nut limiting boss, 35-screw, 36-screw nut, 37-internal threaded tube, 38-joint ball bearing II, 39-internal threaded tube limiting hole, 40-sensor II bonding surface, 41-rigid-flexible switching module protective shell, 42-screw IV, 43-rigid-flexible switching module fixed support boss, 44-gear III, 45-key I, 46-reduction motor, 47-screw V, 48-screw VI, 49-encoder, 50-encoder housing, 51-gear IV, 52-cam connecting rod limiting Fixing nut, 53-key II, 54-cam connecting rod, 55-cam connecting rod boss, 56-screw VII, 57-cross fixing piece, 58-cam, 59-spring II, 60-rack-like mechanism II, 61-cam mechanism base, 62-screw VIII, 63-cam slide groove, 64-control switch I, 65-control switch II, 66-main power switch, 67-main control board, 68-mobile power supply, 69-distribution box, 70-limiting boss, 71-limiting groove, 72-sensor I bonding surface. DETAILED DESCRIPTION

[0035] The invention is further described below in conjunction with the accompanying drawings and embodiments, but the content of the invention is not limited to the scope of the embodiments.

[0036] Example 1: Figure 1-16As shown, a rigid-flexible switching serial elastic driver comprises a support and protection module 1, an external input module 2, a load driving module 3, and a rigid-flexible switching module 4; wherein the support and protection module 1 is used to install the external input module 2, the load driving module 3, and the rigid-flexible switching module 4 to fix, support and protect each module; the external input module 2 is connected to the first connection part through a joint ball bearing I21, and the force of the first connection part is transmitted to the spring I14 in the external input module 2; the load driving module 3 is fixed to the serial elastic driver housing II8 through a screw I12, and is connected to the second connection part through a joint ball bearing II38, and the output torque is provided by the drive motor 25 to drive the second connection part; the rigid-flexible switching module 4 is fixed to the rigid-flexible switching module fixed support boss 43 through screws, and the locking and loosening of the spring I14 are completed under the drive of the reduction motor 46, so as to realize the switching between the rigid mode and the flexible mode.

[0037] Furthermore, the axial direction of the joint ball bearing I21 is parallel to the axial direction of the joint ball bearing II38, and the two are located on opposite sides of the support protection module 1; the joint ball bearing II38 is driven to move left or right by the driving motor 25 after being converted by the load driving module, and the spring I14 moves correspondingly with the left and right movement of the joint ball bearing II38. Figure 1 From a perspective of explanation, when the driving motor 25 drives the joint ball bearing II38 to move to the left, the spring I14 moves to the left and is compressed; when the driving motor 25 drives the joint ball bearing II38 to move to the right, the compression amount of the spring I14 moving to the right is reduced.

[0038] Furthermore, the supporting protection module 1 comprises a serial elastic driver housing I5, a supporting frame 7, and a serial elastic driver housing II8; wherein the serial elastic driver housing I5 is connected to the serial elastic driver housing II8 and the supporting frame 7 is installed between the two.

[0039] like Figure 1-3 As shown, the limiting boss 70 on the serial elastic driver housing II8 in the supporting protection module 1 cooperates with the limiting groove 71 on the supporting frame 7 to limit the supporting frame 7, so as to prevent the supporting frame 7 from shaking left and right during installation, which increases the difficulty of installation. At the same time, the supporting frame 7 is fixed to the serial elastic driver housing I5 by screws I12, and the serial elastic driver housing I5 and the serial elastic driver housing II8 are limited and fixed by the serial elastic driver housing I boss 6 and the serial elastic driver I housing groove 11, and the two housings are connected by screws II13 to increase stability.

[0040] Furthermore, the external input module 2 includes a spring I14, a spring limiting slider 15, a double-headed screw 18, a rack-like mechanism I19, and a joint ball bearing I21; wherein, one end of the joint ball bearing I21 is connected to the first connecting part, the other end of the joint ball bearing I21 is fixed to one end of the double-headed screw 18, the other end of the double-headed screw 18 is connected to one end of the spring limiting slider 15, one end of the spring I14 is sleeved on the other end of the spring limiting slider 15, and the other end of the spring I14 is limited in the axial direction by the support frame 7 in the support protection module 1; the spring limiting slider 15 is slidably matched with the support frame 7; a rack-like mechanism I19 is installed on the double-headed screw 18, and the engagement and non-engagement of the rack-like mechanism II60 and the rack-like mechanism I19 in the rigid-flexible switching module 4 are realized by driving the rigid-flexible switching module 4.

[0041] Furthermore, the spring I14, the spring limiting slider 15, and the double-headed screw 18 are radially limited through the space formed by the support frame 7 and the elastic driver housing I5 in series in the support protection module 1.

[0042] like Figure 4 , 5As shown, the right end of the spring I14 in the external input module 2 is sleeved on the spring limiting slider 15, and the left end of the spring I14 is limited by the spring I limiting boss II22 on the support frame 7 for left and right movement. At the same time, the spring I14 is embedded in the cylindrical space formed by the spring I limiting boss 9 in the serial elastic driver housing I5 and the spring I limiting groove 23 in the support frame 7 to limit the up and down movement of the spring I14; the spring limiting slider 15 is connected to the spring limiting slider limiting groove 16 and the spring limiting slider limiting boss 24 through sliding to ensure that the spring limiting slider 15 slides in the axial direction, and the up and down movement of the spring limiting slider 15 is limited by the space formed by the support frame 7 and the serial elastic driver housing I5; the spring limiting slider The right end of block 15 is connected to the left end of the double-headed screw 18 by threads, and the double-headed screw fixing groove I10 and the double-headed screw fixing groove II20 limit the up and down jumping of the double-headed screw 18, so that the double-headed screw can slide along the axial direction, and the right end of the double-headed screw 18 is fixed to the joint ball bearing I21 by threads; the rack-like mechanism I19 is welded on the double-headed screw 18, and engages with the rack-like mechanism II60 when switching between rigid and flexible, that is, entering the support / rigid mode; when switching between flexible and rigid, the rack-like mechanism I19 is separated from the rack-like mechanism II60, that is, entering the power-assistance / flexible mode; by bonding the displacement sensor I17 to the bonding surface 72 of the sensor I, it is used to measure the displacement of the spring limit slider 15. Among them, the working principle of the displacement sensor is: the positioning column installed in the spring limit slider 15 provides a pressure to the sheet displacement sensor. Along with the movement of the spring limit slider, the positioning column applies a pressure to the displacement sensor at different positions of the displacement sensor. Different positions of the sensor correspond to resistors with different resistance values. The displacement sensor uses the corresponding resistor under the action of pressure; since the total voltage of the sensor remains unchanged when it is working, different resistance values ​​will result in different currents. The sensor determines the position of the spring limit slider according to the size of the current, and the main control board obtains the compression of the spring according to the position.

[0043] The above technical solution uses two outer shells and a load bracket to fix the internal parts through limiting bosses and screws. On the one hand, this design can limit multiple parts (such as deep groove ball bearings, spring limiting sliders, double-headed screws, and lead screw nuts) in various directions, so that the matching accuracy of the parts of the device can be guaranteed when it is working, and the connection strength of the internal parts can be fully guaranteed. At the same time, the replacement efficiency of internal damaged parts can be greatly improved, and the device is more versatile. On the other hand, the compact internal parts structure of the device makes the volume occupied by the entire device relatively small, and the outer shell and load support frame of the device can be processed using lightweight materials such as plastic, which can improve the difficulties in the lightweight design of the exoskeleton.

[0044] Furthermore, the load driving module 3 includes a driving motor 25, a gear I26, a gear II31, a deep groove ball bearing 32, a screw 35, a screw nut 36, an internal threaded tube 37, and a joint ball bearing II38; wherein the driving motor 25 is fixed on the load support frame 7 in the support protection module 1, the gear I26 is fixed on the output shaft of the driving motor 25, the gear I26 is meshed with the gear II31 for transmission, the gear II31 is fixed to the top of the screw 35, the deep groove ball bearing 32 is fixed on the screw 35, the screw nut 36 is meshed with the screw 35 for transmission, one end of the internal threaded tube 37 is fixedly connected to the screw nut 36, and the other end of the internal threaded tube 37 passes through the internal threaded tube limiting hole 39 in the load support frame 7 and is fixedly connected to the joint ball bearing II38, and the joint ball bearing II38 is connected to the second connecting part to convert the output torque of the driving motor into a driving torque to drive the second connecting part.

[0045] like Figure 6 , 7 As shown, in the load driving module 3, the driving motor 25 is fixed to the load supporting frame 7 by means of screws III28, the gear I26 is fixed to the output shaft of the driving motor 25 by means of gear top screws 27, the gear I26 is meshed with the gear II31 for transmission, the gear II31 is fixed to the top of the screw rod 35 by means of the gear top screws 27, the deep groove ball bearing 32 is fixed to the screw rod 35 by means of interference fit, the deep groove ball bearing fixing grooves I29 and II33 are used to limit and fix the deep groove ball bearing 32, the screw nut 36 is meshed with the screw rod 35 for transmission The left end of the internal threaded tube 37 is fixedly connected to the screw nut 36 by threads, and the right end of the internal threaded tube 37 passes through the internal threaded tube limiting hole 39 and is fixedly connected to the joint ball bearing II38 by threads. The joint ball bearing II38 is connected to the outside world through a second connection part, and the motor output torque is converted into a driving torque to drive the second connection part. The screw nut 36 jumps up and down and is limited by the space formed by the support frame 7 and the screw nut limiting boss 34; the displacement sensor II30 is bonded to the sensor II bonding surface 40, and its corresponding positioning column is installed in the screw nut 36.

[0046] Furthermore, the rigid-flexible switching module is powered by a reduction motor 46, and the rotation of the reduction motor 46 drives the rotation of the gear III44, and the gear III44 meshes with the gear IV51. The rotation of the gear IV51 drives the rotation of the cam link 54, and the cam link boss 55 at one end of the cam link 54 slides in the cam groove 63 in the cam 58, so as to convert the rotation of the cam link 54 into the up and down movement of the cam 58 along the axial direction, and the rack-like mechanism II60 moves with the cam 58, and the up and down movement of the rack-like mechanism II60 realizes the engagement and non-engagement with the rack-like mechanism I19.

[0047] Furthermore, the rigid-flexible switching module includes a gear III44, a reduction motor 46, a gear IV51, a cam limit fixing nut 52, a cam connecting rod 54, a cam connecting rod boss 55, a cam 58, a spring II59, a rack-like mechanism II60, a cam mechanism base 61, and a cam slide 63; wherein the reduction motor 46 and the cam mechanism base 61 are fixed to the outer side of the series elastic driver housing I5 in the support protection module 1, the gear III44 fixed on the output shaft of the reduction motor 46 is meshed with the gear IV51, and the gear IV51 is fixed to the cam On the top rotating shaft of the connecting rod 54, the cam connecting rod boss 55 at the other end of the cam connecting rod 54 cooperates with the cam slide groove 63 in the cam 58; the spring II59 is sleeved on the cam 58, and the spring II59 and the cam 58 are placed as a whole in the cylindrical hole of the cam mechanism base 61, and the cam limit fixing nut 52 sleeved on the cam connecting rod 54 is fixedly connected to one end of the cam mechanism base 61; the rack-like mechanism II60 is fixed at one end of the cam 58 and extends from the other end of the cam mechanism base 61, and the rack-like mechanism II60 is meshed with the rack-like mechanism I19 for locking the spring I14.

[0048] Furthermore, the other end of the cam 58 is fixed to the cross fixing piece 57 , and the lower end surface of the cross fixing piece 57 is tangent to the surface of the cam sliding groove 63 .

[0049] like Figure 8-Figure 15As shown, the reduction motor 46 and the encoder housing 50 in the rigid-flexible switching module are fixed to the rigid-flexible switching module fixed support boss 43 on the outside of the series elastic driver housing I5 by screws V47 (wherein the encoder 49 is fixed in the encoder housing 50 by screws VI48), the gear III44 is fixed to the reduction motor output shaft by key I45, and is fixed with the gear IV51, the gear IV51 is fixed to the top rotating shaft of the cam connecting rod 54 by key II53, and the rotation of the reduction motor 46 is converted into the rotation of the cam connecting rod 54, the cam connecting rod boss 55 at one end of the cam connecting rod 54 slides in the cam slide groove 63 in the cam 58, and the rotation of the cam connecting rod 54 is converted into the up and down movement of the cam 58 along the axial direction; the cross fixing piece 57 is fixed to the cam 58 by screws VII56 to facilitate the installation of the cam connecting rod boss 55, and the lower end surface of the cross fixing piece 57 is fixed to the cam The surface of the wheel slide groove 63 is tangent to each other, so that the surface of the cam slide groove is flat and smooth, preventing the cam connecting rod boss 55 from getting stuck when it moves to the position of the cross fixing piece 56; the spring II59 is sleeved on the lower end of the cam 58, and the spring II59 and the cam 58 are placed as a whole in the cylindrical hole of the cam mechanism base 61, and can slide up and down in the cylindrical hole, and the cam limit fixing nut 52 sleeved on the cam connecting rod 54 is fixed to the cam mechanism base 61 by a threaded connection, which is used to protect the components installed on the cam mechanism base 61 and limit the position; the rack-like mechanism II60 is welded to the lower end of the cam 58, and can engage with the rack-like mechanism I19 to lock the spring I14, and the cam mechanism base 61 is fixed to the rigid-flexible switching module fixed support boss 43 by screws VIII62, and the rigid-flexible switching module protective shell 41 is fixed to the rigid-flexible switching module fixed support boss 43 by screws IV42, so as to protect the entire rigid-flexible switching module.

[0050] The above technical solution switches between rigid mode and flexible mode by using a cam mechanism with a left-right symmetrical groove embedded inside to convert the rotation of the reduction motor into the up and down movement of a rack-like mechanism. The reduction motor rotates in one direction during the entire working process to achieve the engagement and disconnection of a pair of rack-like mechanisms, which is convenient for control and can increase the life of the motor (or the length of use). At the same time, the engagement of the rack-like mechanism does not need to consider the position, so that the rigid-flexible switching can be completed in real time, which improves the efficiency of the rigid-flexible switching and increases the convenience of use.

[0051] Furthermore, if Fig.16The present invention shown also includes a control switch I64, a control switch II65, a main power switch 66, a main control board 67, a mobile power supply 68, and a distribution box 69; wherein the control switch I64, the control switch II65, the main power switch 66, the main control board 67, and the mobile power supply 68 are fixed to the distribution box 69 by screws, the main power switch 66 controls the on and off of the power supply, the control switch I64 controls the switching of the device between the rigid mode and the flexible mode, the control switch II65 controls the output of different forces at the second connecting part of the device, the main control board 67 processes the signal transmitted by the sensor and sends instructions to control the entire device, and the mobile power supply 68 provides power for the device.

[0052] The optional process of the present invention is described as follows: the present invention is used in conjunction with a waist exoskeleton robot, and can also be used for other applicable robots. Three examples of different usage scenarios are given:

[0053] First, the control switch II is explained as follows: the control switch II65 has four switches representing different Δx values. Under these four different Δx values, the driving motor 25 can output four different forces. When using the device, different switches can be used according to different needs to achieve the conversion of four different output forces. Δx represents the compression of the spring; when the spring I is in a natural extension state, the Δx value is 0; when the spring limit slider contacts the double-headed screw fixing groove II20, the spring I is in a natural extension state. Different numbers of switches can also be set according to needs.

[0054] Scene 1: Assisted mode.

[0055] The articulated ball bearing I21 is connected to the first connection part, and the articulated ball bearing II38 is connected to the second connection part (when used for a waist exoskeleton robot, the first connection part can be an upper bracket, and the second connection part can be a lower bracket). After the wearer completes putting on the waist exoskeleton robot, press the main power switch to turn on 66, and the mobile power supply 68 provides power to the device. At this time, press the corresponding control switch II65 according to the actual output force required, and the device automatically completes the corresponding movement to reach a pre-set state, and all preparations for the device are completed. When the input force of the first connection part connected to the joint ball bearing I21 changes, it is transmitted to the spring I14 through the joint ball bearing I21, the double-headed screw 18, and the spring limit slider 15. The spring I14 is compressed or extended under the action of the force, and the spring limit slider 15 changes along with the change of the spring I14. The displacement sensor I17 measures the displacement change of the spring limit slider 15 and transmits the displacement information to the main control board 67. The main control board obtains the compression amount Δx1 of the spring at the current position after processing according to the measured displacement. At the same time, the displacement of the screw nut 36 is measured by the displacement sensor II30. The displacement is transmitted to the main control board and processed to obtain the current position of the second connection part. Then, the main control board sends instructions to control the drive motor 25 to rotate forward or reverse according to the converted Δx1 value and the processed position of the second connection part. After the drive motor 25 is started, the output torque is transmitted to the screw rod 35 through the meshing transmission of gear I26 and gear II31. The torque is converted into a force along the axis direction of the screw rod nut 36 through the meshing of the screw rod 35 and the screw nut 36. Then, the force is transmitted to the second connection part through the internal threaded tube 37 and the joint ball bearing II38, driving the second connection part to move (i.e., Figure 1 For example, the internal threaded tube 37 is driven to move left or right) until the displacement sensor I17 obtains the displacement Δx1=Δx. When the wearer uses the device for rehabilitation assistance, the above control driving process is repeated to continuously assist the wearer. Whether the drive motor is started or not is driven by the signal measured by the displacement sensor I (when the spring I is locked, the signal measured by the displacement sensor I does not change, and the drive motor does not start).

[0056] Scenario 2: Convert from assist mode to support mode.

[0057] During the use of the device, according to the needs of the wearer, the device can complete the conversion from the power-assist mode to the support mode. When the wearer needs to support the waist, the control switch I64 is manually turned, and then the main control board 67 sends an instruction to control the reduction motor 46 to start clockwise rotation through a fixed angle, which is measured by the encoder 49. The output torque of the reduction motor is transmitted to the cam link 54 through the gear III44 and the gear IV51, so that the cam link 54 rotates counterclockwise through a fixed angle, and the cam link boss 55 slides in the cam slide groove 63 along with the rotation of the cam link 54. The cam link boss 55 slides in the cam slide groove 63 to make the cam 58 move downward, and the downward movement of the cam 58 drives the rack-like mechanism II60 to move downward, completing the meshing with the rack-like mechanism I19, and the spring I14 is locked. The joint ball bearing I21 of the device will not cause the spring I14 to move due to the change in the size of the external input force. At this time, the device loses the entire power-assist movement process, and the device completes the transformation from the flexible mode to the rigid mode, which plays a supporting role for the waist.

[0058] Scenario 3: In an emergency, the device quickly switches between flexible mode and rigid mode to protect the wearer.

[0059] When the device is working in the power-assist mode, if the force of the first connection part connected to the joint ball bearing I21 changes very quickly, causing the spring I14 to change quickly, the displacement sensor I17 measures the rapidly changing displacement and transmits the rapidly changing displacement to the main control board, which processes the corresponding Δx value. If the rate of change of the Δx value exceeds the Δx threshold value pre-set by the system to ensure the wearer's safe movement, the main control board immediately sends a command to control the reduction motor to start and complete the transition from the flexible mode to the rigid mode in the second scene, so that the device changes from the power-assist mode to the support mode, and supports the patient in time to avoid secondary waist injuries to the wearer when using the device. When the wearer needs to use the power-assist mode of the device again, pull the control switch I64 to control the reduction motor 46 to start, complete the device's transition from the rigid mode to the flexible mode, and continue to provide power assistance to the wearer.

[0060] The specific implementation modes of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A rigid-flexible switching series elastic actuator, characterized by: The invention comprises a support protection module (1), an external input module (2), a load drive module (3), and a rigid-flexible switching module (4); wherein the support protection module (1) is used to install the external input module (2), the load drive module (3), and the rigid-flexible switching module (4); the external input module (2) is connected to a first connection part via a joint ball bearing I (21), and transmits the force of the first connection part to a spring I (14) in the external input module (2); the load drive module (3) is connected to a second connection part via a joint ball bearing II (38), and the drive motor (25) provides an output torque to drive the second connection part; and the rigid-flexible switching module (4) completes the locking and loosening of the spring I (14) under the drive of a reduction motor (46), thereby realizing the switching between a rigid mode and a flexible mode; The external input module (2) comprises a spring I (14), a spring limiting slider (15), a double-headed screw (18), a rack-like mechanism I (19), and a joint ball bearing I (21); wherein one end of the joint ball bearing I (21) is connected to the first connection portion, the other end of the joint ball bearing I (21) is fixed to one end of the double-headed screw (18), the other end of the double-headed screw (18) is connected to one end of the spring limiting slider (15), one end of the spring I (14) is sleeved on the other end of the spring limiting slider (15), and the other end of the spring I (14) is axially limited by a support frame (7) in the support protection module (1); the spring limiting slider (15) is slidably matched with the support frame (7); the rack-like mechanism I (19) is installed on the double-headed screw (18), and the meshing and non-meshing of the rack-like mechanism II (60) in the rigid-flexible switching module (4) and the rack-like mechanism I (19) are achieved by driving the rigid-flexible switching module (4); The load driving module (3) comprises a driving motor (25), a gear I (26), a gear II (31), a deep groove ball bearing (32), a screw (35), a screw nut (36), an internally threaded tube (37), and a joint ball bearing II (38); wherein the driving motor (25) is fixed on a load supporting frame (7) in the supporting and protecting module (1), the gear I (26) is fixed on an output shaft of the driving motor (25), the gear I (26) meshes with the gear II (31) for transmission, and the gear II (31) The deep groove ball bearing (32) is fixed on the top of the screw rod (35), the screw nut (36) is meshed with the screw rod (35) for transmission, one end of the internal threaded tube (37) is fixedly connected to the screw nut (36), the other end of the internal threaded tube (37) passes through the internal threaded tube limiting hole (39) in the load support frame (7) and is fixedly connected to the joint ball bearing II (38), and the joint ball bearing II (38) is connected to the second connection part to convert the output torque of the driving motor into a driving torque to drive the second connection part; The rigid-flexible switching module is powered by a reduction motor (46), and the rotation of the reduction motor (46) drives the rotation of gear III (44), and gear III (44) meshes with gear IV (51). The rotation of gear IV (51) drives the rotation of the cam link (54), and the cam link boss (55) at one end of the cam link (54) slides in the cam groove (63) in the cam (58), converting the rotation of the cam link (54) into an up-and-down movement of the cam (58) along the axis, and the rack-like mechanism II (60) moves with the cam (58), and the up-and-down movement of the rack-like mechanism II (60) realizes meshing and non-meshing with the rack-like mechanism I (19).

2. The rigid-flexible switching series elastic actuator according to claim 1, characterized in that: The axial direction of the joint ball bearing I (21) is parallel to the axial direction of the joint ball bearing II (38), and both are located on opposite sides of the support protection module (1).

3. The rigid-flexible switching series elastic actuator according to claim 1, characterized in that: The support protection module (1) comprises a serial elastic drive housing I (5), a support frame (7), and a serial elastic drive housing II (8); wherein the serial elastic drive housing I (5) is connected to the serial elastic drive housing II (8) and the support frame (7) is installed between the two.

4. The rigid-flexible switching series elastic actuator according to claim 1, characterized in that: The spring I (14), the spring limiting slider (15), and the double-headed screw (18) are radially limited through a space formed by the support frame (7) and the elastic driver housing I (5) connected in series in the support protection module (1).

5. The rigid-flexible switching series elastic actuator according to claim 1, characterized in that: The rigid-flexible switching module comprises a gear III (44), a reduction motor (46), a gear IV (51), a cam limit fixing nut (52), a cam connecting rod (54), a cam connecting rod boss (55), a cam (58), a spring II (59), a rack-like mechanism II (60), a cam mechanism base (61), and a cam slide groove (63); wherein the reduction motor (46) and the cam mechanism base (61) are fixed to the outside of the series elastic driver housing I (5) in the supporting protection module (1); the gear III (44) fixed on the output shaft of the reduction motor (46) is meshed with the gear IV (51); the gear IV (51) is fixed to the cam connecting rod ( 54), the cam link boss (55) at the other end of the cam link (54) cooperates with the cam groove (63) in the cam (58); the spring II (59) is sleeved on the cam (58), and the spring II (59) and the cam (58) are placed in the cylindrical hole of the cam mechanism base (61) as a whole. The cam limit fixing nut (52) sleeved on the cam link (54) is fixedly connected to one end of the cam mechanism base (61); the rack-like mechanism II (60) is fixed to one end of the cam (58) and extends from the other end of the cam mechanism base (61), and the rack-like mechanism II (60) is meshed with the rack-like mechanism I (19) to lock the spring I (14).

6. The rigid-flexible switching series elastic actuator according to claim 5, characterized in that: The other end of the cam (58) is fixed to a cross fixing piece (57), and the lower end surface of the cross fixing piece (57) is tangent to the surface of the cam sliding groove (63).

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