Force feedback type full-drive end effector

Abstract

The utility model relates to a force feedback type full-drive end effector which comprises a base connected with the output end of a mechanical arm, a plurality of flexible fingers hinged to the top end of the base and distributed in the circumferential direction, and a driving device arranged corresponding to the flexible fingers and driving the flexible fingers to abut against a clamped object. A main control chip board electrically connected with the driving device is further arranged on the base, and a pressure sensor abutting against the clamped object is further arranged on the side face, clamping the clamped object, of the flexible finger. According to the utility model, each finger of the end effector is provided with an independent steering engine, so that each clamping jaw is independently controlled; by installing a pressure sensor, experimental data can be analyzed conveniently, and therefore accurate control over the clamping force is achieved; compared with a traditional under-actuated end effector, the under-actuated end effector can effectively solve the problems that clamping is not tight, clamped objects are damaged, and various clamped objects cannot be clamped in a self-adaptive mode in the clamping process.

Description

Technical Field

[0001] The utility model relates to the field of machinery, in particular to the field of mechanical end technology, and specifically refers to a force feedback type full-drive end actuator. Background Art

[0002] Most multi-finger end effectors have insufficient driving force, that is, they have greater freedom in mechanical structure design but the number of drivers is less than the freedom of the fingers. Although this driving scheme can reduce the number of drivers to save costs, the control accuracy needs to be improved.

[0003] In addition, the auxiliary grasping perception system is also lacking, which makes the control of the clamping force during operation inaccurate. These two problems greatly affect the operation quality and efficiency of the end effector. Therefore, there is an urgent need for a full-drive end effector that can accurately control the grasping force. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a force feedback type full-drive end effector, which can realize individual control of fingers and ensure accurate control of the gripping force of the fingers.

[0005] The utility model is realized through the following technical scheme: a force feedback full-drive end effector, comprising a base connected to the output end of a robotic arm, a plurality of flexible fingers hinged on the top of the base and arranged circumferentially, and a driving device arranged corresponding to the flexible fingers and driving the flexible fingers to push onto the clamped object; the base is also provided with a main control chip board electrically connected to the driving device.

[0006] When the utility model is in use, the base is connected to the mechanical arm, and then a plurality of fingers are pushed onto the clamped object, so that the clamped object is grasped. Each finger is moved by a correspondingly arranged driving device, so each finger moves independently, thereby realizing individual control of the fingers.

[0007] Preferably, a pressure sensor pressing against the clamped object is also provided on the side of the flexible finger that clamps the clamped object.

[0008] When this preferred solution is in use, the pressure sensor is set up so that it can respond in real time to the pressure between the finger and the clamped object, thereby ensuring the clamping strength of the finger, thereby achieving precise control of the clamping force. Since the fingers are controlled individually, it solves the problems of not clamping the object tightly, damaging the clamped object, and not being able to adaptively clamp a variety of clamped objects, thereby ensuring the operating quality and efficiency of the end effector.

[0009] Preferably, the driving device comprises a steering gear, a driving gear arranged on an output shaft of the steering gear, and a driven gear meshing with the driving gear and arranged on the flexible finger.

[0010] This preferred solution realizes the rotation of the finger by setting a steering gear, a driving gear, and a driven gear.

[0011] Preferably, the base is provided with a through hole penetrating the base, and the main control chip board is arranged in the through hole.

[0012] The preferred solution facilitates the installation and removal of the main control chip board and subsequent maintenance through the setting of the perforations.

[0013] Preferably, a silicone pad is provided on the side of the flexible finger gripping the clamped object, and the pressure sensor is arranged on the silicone pad.

[0014] In this preferred solution, the friction between the finger and the clamped object is increased by providing a silicone soft pad.

[0015] Preferably, three pressure sensors are provided, and the three pressure sensors are arranged along the height direction.

[0016] In this preferred solution, three pressure sensors are arranged to form a pressure sensor array, thereby ensuring that the pressure sensors can be pressed against the clamped object.

[0017] Preferably, a groove extending downward is provided at the top of the base, and a silicone pad is provided on the bottom of the groove.

[0018] In this preferred solution, the object to be clamped is located in the groove by setting the groove, so that when the fingers clamp the object with a large height, the stability of the clamping of the object is guaranteed.

[0019] Preferably, the side surface provided with the pressure sensor is a curved surface adapted to the side surface of the clamped object.

[0020] This preferred solution improves the gripping strength of fingers on the gripped object by setting the curved surface.

[0021] The beneficial effects of the utility model are as follows: by installing a separate servo on each finger of the end effector, individual control of each clamping jaw is achieved; by installing a pressure sensor, it is convenient to analyze experimental data, thereby achieving precise control of the clamping force; compared with the traditional under-actuated end effector, this solution can effectively solve the problems of loose clamping, damage to the clamped object, and inability to adaptively clamp a variety of clamped objects in the clamping process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional schematic diagram of the structure of the utility model;

[0023] Figure 2 It is a three-dimensional schematic diagram of the initial state of the structure of the utility model;

[0024] Figure 3 It is a schematic diagram of the structure of the utility model close to the clamped object;

[0025] Figure 4 It is a schematic diagram of the flexible finger gripping an object;

[0026] Figure 5 It is a schematic diagram of the structure of the utility model carrying the clamped object out of the original position;

[0027] As shown in the figure:

[0028] 1. Silicone pads on fingers, 2. Flexible fingers, 3. Driven gears, 4. Base, 5. Main control chip board, 6. Pressure sensor, 7. Groove bottom, 8. Axis pin, 9. Through hole, 10. Driving gear, 11. Servo, 12. Card slot, 13. Connecting plate. DETAILED DESCRIPTION

[0029] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.

[0030] See attached Figure 1-5 The utility model discloses a force feedback full-drive end effector, comprising a silicone soft pad 1, a flexible finger 2, a driven gear 3, a base 4, a main control chip board 5, a pressure sensor 6, an axle pin 8, a through hole 9, a driving gear 10, a steering gear 11, a card slot 12 and a connecting plate 13 connected to the output end of the mechanical arm.

[0031] The base 4 is completed by 3D printing, and plays the role of connecting and supporting the whole. A through hole is provided on the lower side of the base 4, and a main control chip board 5 is installed in the through hole. Four card slots 12 are provided in the middle of the base, and a servo 11 electrically connected to the main control chip board is placed in the card slot. A through hole 9 is provided on the base above the card slot 12.

[0032] There are also four flexible fingers arranged circumferentially above the base and corresponding to the servos. The flexible fingers are formed by injection molding. The flexible fingers 2 are inserted into the through holes and hinged to the base through the axle pin 8. The output shaft of the servo 11 is connected to the driving gear 10. The rotation of the output shaft of the servo drives the driving gear to rotate. The fingers are also fixed with a driven gear located below the pin shaft and meshing with the driving gear. The circumferential surface of the driven gear is fixed to the fingers, and the axis of the driven gear is arranged parallel to the axis of the pin shaft.

[0033] The side where the finger contacts the clamped object is a plane, and a strip-shaped silicone pad 1 is provided on this side to increase the friction during clamping. Three pressure sensors placed on the silicone pad 1 are also provided on this side. The three pressure sensors are arranged along the height direction, and the three pressure sensors are grouped together to form a pressure sensor array for accurately measuring the force during grasping. The pressure sensors are electrically connected to the main control chip board.

[0034] At the same time, the side of the finger that contacts the clamped object is a curved surface that matches the side of the clamped object, so it is suitable for clamping the corresponding object.

[0035] In addition, a downwardly extending groove is provided at the top of the base, and a silicone pad is also provided on the bottom of the groove. The silicone pad is circular and fits the bottom of the groove. A connecting plate 13 is installed at the bottom of the base for connecting to the robotic arm. The connecting plate is prior art.

[0036] When the utility model is in use:

[0037] Action 1: Connect the end effector to the end of the robot arm through the connecting plate 13, use the computer to control the robot arm, and slowly control the end effector to move to the working position.

[0038] Action 2: The main control chip board 5 controls the steering gear 11 to rotate, and the steering gear 11 rotates to drive the driving gear 10 to rotate. The driving gear 10 meshes with the driven gear 3 to rotate, thereby driving the flexible finger 2 to rotate. By controlling the four steering gears 11 to rotate to the corresponding angles, the four flexible fingers 2 on the end effector are controlled to reach the working position. At this time, the four steering gears 11 stop running.

[0039] Action 3: After reaching the initial state, the pressure sensor array 6 also initializes and runs. The flexible finger 2 approaches the object to be clamped. When it contacts the object, the pressure sensor 6 starts to read the pressure sensor data and uploads it to the main control chip board 5. At this time, the flexible finger 2 will wrap the object to be clamped. When the pressure reaches a predetermined value, the main control chip 5 sends a control signal to control the injection molding flexible finger 2 to stop wrapping the fruit.

[0040] Action 4: The computer controls the robot arm to move to the termination position. At this time, the end effector relies on the friction force provided by the silicone pad 1 to remove the clamped object from its original position.

[0041] Action 5: The main control chip board 5 controls the steering gear 11 to rotate, and the steering gear 11 rotates to drive the driving gear 10 to rotate. The driving gear 10 meshes with the driven gear 3 to rotate, thereby driving the flexible fingers 2 to rotate. The four steering gears 11 are controlled to rotate in the opposite direction to a corresponding angle, so that the clamped object is separated, and the angles of the four flexible fingers 2 are initialized, waiting for the next operation.

[0042] In particular, in the initial state, the outer side of the flexible finger 2 is 90° to the base 4, and the inner side of the flexible finger 2 is 120° to the base 4. The inner side of the flexible finger 2 is the side for clamping the object. Figure 2-5 In the examples above, we take the clamping of apples as an example, that is, the clamped object is an apple, and Figure 4-5 This is a schematic diagram when the side surface where the finger contacts the clamped object is a curved surface.

[0043] Of course, the above description is not limited to the above examples. The technical features not described in the present invention can be achieved by or by adopting the existing technology, which will not be repeated here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that the changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not deviate from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A force feedback full-drive end effector, characterized in that: The invention comprises a base (4) connected to the output end of the robot arm, a plurality of flexible fingers (2) hinged to the top of the base (4) and arranged in a circumferential direction, and a driving device arranged corresponding to the flexible fingers (2) and driving the flexible fingers (2) to push against the clamped object. The base (4) is also provided with a main control chip board (5) electrically connected to the driving device.

2. The force feedback full-drive end effector according to claim 1, characterized in that: A pressure sensor (6) that presses against the clamped object is also provided on the side of the flexible finger (2) that clamps the clamped object.

3. The force feedback full-drive end effector according to claim 2, characterized in that: The driving device comprises a steering gear (11), a driving gear (10) arranged on an output shaft of the steering gear (11), and a driven gear (3) meshing with the driving gear (10) and arranged on a flexible finger (2).

4. The force feedback full-drive end effector according to claim 1, characterized in that: The base (4) is provided with a through hole which penetrates the base (4), and the main control chip board (5) is arranged in the through hole.

5. The force feedback full-drive end effector according to claim 2, characterized in that: A silicone pad is provided on the side of the flexible finger gripping the object, and the pressure sensor (6) is arranged on the silicone pad.

6. The force feedback full-drive end effector according to claim 2, characterized in that: The pressure sensors (6) are provided in three numbers, and the three pressure sensors (6) are arranged along the height direction.

7. The force feedback full-drive end effector according to claim 1, characterized in that: The top of the base (4) is provided with a groove extending downwards, and a silicone cushion is provided on the bottom (7) of the groove.

8. The force feedback full-drive end effector according to claim 2, characterized in that: The side surface provided with the pressure sensor (6) is a curved surface adapted to the side surface of the clamped object.

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