Mechanical finger and bionic mechanical hand

Abstract

The present invention relates to a bionic manipulator. In the first aspect, a mechanical finger is disclosed, including a mounting portion, a knuckle unit, a fingertip unit and a driving portion. A forward four-bar mechanism is used in the knuckle unit, and a reverse four-bar mechanism is used in the fingertip unit. The first connecting segment of the knuckle unit and the second connecting segment of the fingertip unit are hinged to link the forward four-bar mechanism and the reverse four-bar mechanism. The driving portion drives the driving segment in the knuckle unit to swing, thereby driving the forward four-bar mechanism and the reverse four-bar mechanism to move together, so that the knuckle segment of the knuckle unit and the fingertip segment of the fingertip unit are folded or straightened together, simulating the movement of fingers during grasping and releasing of the hand. In the second aspect, a bionic manipulator is disclosed, including the above-mentioned mechanical finger. The beneficial effects are as follows: on the premise of ensuring the grasping function of the bionic manipulator, the structure of the mechanical finger is optimized, the structure is more concise and ingenious, the debugging is more convenient, and it can adapt to a variety of grasping surfaces with different shapes.

Description

Technical Field

[0001] The invention relates to a bionic manipulator, in particular to a mechanical finger and a bionic manipulator. Background Art

[0002] A bionic manipulator is a manipulator that uses a mechanical structure to simulate the movement of a real human hand. It can be used in industries such as industrial automation and medical care to simulate human hands and play a corresponding role. Just like a human hand, the key part of a bionic manipulator is to simulate the movement of fingers on a human hand by designing the structure of the mechanical fingers. This also directly determines whether the grasping function of the bionic manipulator is perfect and how close it is to a human hand. Current mechanical fingers generally include a mounting part, a section of knuckles, a section of fingertips, and a driving mechanism. The knuckles swing relative to the mounting part, and the fingertips swing relative to the knuckles. The specific driving mechanism methods are varied. Under the premise of ensuring the grasping function of the bionic manipulator, the structure of existing mechanical fingers is generally complex, the assembly and debugging are cumbersome, and the user experience is poor. Summary of the invention

[0003] The present application provides a mechanical finger and a bionic mechanical hand, which can solve the problems that the existing mechanical fingers are generally complex in structure, cumbersome in assembly and debugging, and poor in user experience.

[0004] In a first aspect, the present application provides a mechanical finger, comprising:

[0005] Installation Department;

[0006] The finger joint unit comprises: a finger joint segment, a driving segment and a first connecting segment which form a positive four-bar mechanism with the mounting portion; the finger joint segment is driven to swing in the same direction relative to the mounting portion by the swing of the driving segment relative to the mounting portion;

[0007] The fingertip unit comprises: a fingertip segment and a second connecting segment which form a reverse four-bar mechanism with the finger segment and the first connecting segment; the fingertip segment is driven to swing in the reverse direction relative to the finger segment by the swing of the first connecting segment relative to the finger segment;

[0008] The driving part is arranged on the mounting part and drives the driving section to swing relative to the mounting part.

[0009] Furthermore, the driving part includes: a linear drive and a third connecting section; the cylinder of the linear drive is fixed to the mounting part; one end of the third connecting section is hinged to the telescopic rod of the linear drive, and the other end is hinged to the driving section to form a crank slider mechanism.

[0010] Furthermore, the mechanical finger also includes: an elastic member, which acts on the knuckle unit and the fingertip unit to make the fingertip segment and the knuckle segment tend to straighten.

[0011] Furthermore, the elastic member is a tension spring, one end of which is connected to the second connecting section, and the other end of which is connected to the finger segment.

[0012] Furthermore, the positive four-bar mechanism formed by the mounting portion, the finger segment, the driving segment and the first connecting segment is in the shape of a parallelogram.

[0013] Furthermore, the finger segment is provided with a through slot for the second connecting segment to pass through; a first hinge point on the finger segment for the first connecting segment to be hinged and a second hinge point on the finger segment for the mounting portion to be hinged are respectively located on both sides of the through slot.

[0014] Furthermore, the driving segment and the second connecting segment have hinge points on the first connecting segment that coincide with each other.

[0015] Furthermore, the hinge points of the third connecting segment and the first connecting segment on the driving segment coincide with each other.

[0016] Furthermore, the linear drive is an electric cylinder.

[0017] In a second aspect, the present application further provides a bionic robotic arm, comprising: any one of the robotic fingers in the first aspect.

[0018] In summary, in the present application, a mechanical finger comprises a mounting portion, a knuckle unit, a fingertip unit and a driving portion. A forward four-bar linkage is used in the knuckle unit, and a reverse four-bar linkage is used in the fingertip unit. The first connecting segment of the knuckle unit and the second connecting segment of the fingertip unit are hinged to link the forward four-bar linkage and the reverse four-bar linkage. The driving portion drives the driving segment in the knuckle unit to swing, thereby driving the forward four-bar linkage and the reverse four-bar linkage to move together, so that the knuckle segment of the knuckle unit and the fingertip segment of the fingertip unit are folded or straightened together, simulating the movement of the fingers of the hand during grasping and releasing. A bionic manipulator comprises the above-mentioned mechanical finger. Beneficial effects: Under the premise of ensuring the grasping function of the bionic manipulator, the structure of the mechanical finger is optimized, the structure is more concise and ingenious, the debugging is more convenient, and it can adapt to a variety of grasping surfaces with different shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0020] Figure 1 It is a schematic diagram of the structure of the mechanical finger;

[0021] Figure 2 is a side view of the mechanical finger and a cross-sectional view of the side;

[0022] Figure 3 The schematic diagram of the forward four-bar mechanism when the mechanical finger is extended and the schematic diagram when it is retracted;

[0023] Figure 4 It is a schematic diagram corresponding to the reverse four-bar mechanism when the mechanical finger is extended and the schematic diagram corresponding to the mechanical finger when it is retracted;

[0024] Figure 5 The schematic diagram of the driving part when the mechanical finger is extended and the schematic diagram when it is closed;

[0025] Figure 6 It is a schematic diagram of the robotic finger being straightened, a schematic diagram between being stretched and folded, and a schematic diagram of being folded.

[0026] In the figure,

[0027] 1. Installation department;

[0028] 2. Knuckle unit; 2a. Knuckle segment; 2a1. First hinge point; 2a2. Second hinge point; 2a3. Third hinge point; 2a4. Through slot; 2a5. First outer shell; 2b. Driving segment; 2c. First connecting segment;

[0029] 3. fingertip unit; 3a. fingertip segment; 3a1. fourth hinge point; 3a2. fifth hinge point; 3a3. second outer shell; 3b. second connecting segment;

[0030] 4. Driving unit; 4a. Linear drive; 4b. Third connecting section;

[0031] 5. Elastic parts;

[0032] 2-1, forward four-bar linkage; 2-1a, first connecting line; 2-1b, second connecting line; 2-1c, angle 1;

[0033] 3-2, reverse four-bar linkage; 3-2a, angle 2; 3-2b, angle 3. DETAILED DESCRIPTION

[0034] The following is further explained in conjunction with the accompanying drawings. Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0035] See also Figure 1 and Figure 2 A mechanical finger includes a mounting part 1, a finger joint unit 2, a fingertip unit 3 and a driving part 4.

[0036] The mounting portion 1 is used to mount the remaining components on the mechanical finger and to mount the mechanical finger to the bionic mechanical hand.

[0037] See also Figure 2 and Figure 3 The finger joint unit 2 includes a finger joint segment 2a, a driving segment 2b and a first connecting segment 2c. The finger joint segment 2a, the driving segment 2b, the first connecting segment 2c and the mounting portion 1 form a positive four-bar mechanism 2-1. More specifically, the side of the finger joint segment 2a close to the mounting portion 1 is provided with a first hinge point 2a1 and a second hinge point 2a2; the first end of the driving segment 2b is hinged to the mounting portion 1; the first hinge point 2a1 of the finger joint segment 2a is hinged to the mounting portion 1; the first end of the first connecting segment 2c is hinged to the second end of the driving segment 2b, and the second end of the first connecting segment 2c is hinged to the second hinge point 2a2 of the finger joint segment 2a.

[0038] For the forward four-bar mechanism 2-1, the swing of the driving segment 2b relative to the mounting portion 1 drives the finger segment 2a to swing in the same direction relative to the mounting portion 1. Considering the required range of motion of the finger segment 2a simulating a human finger, the forward four-bar mechanism 2-1 can be a double rocker.

[0039] See also Figure 1 and Figure 2 In addition, in order to better meet the bionics and aesthetics of the finger, a first outer shell 2a5 of a corresponding shape can be installed on the finger segment 2a. More specifically, the first outer shell 2a5 can be divided into two parts, which are respectively installed on the left and right sides of the finger segment 2a.

[0040] See also Figure 2 and Figure 4 , the fingertip unit 3 includes a fingertip segment 3a and a second connecting segment 3b. The finger segment 2a, the first connecting segment 2c, the fingertip segment 3a and the second connecting segment 3b form a reverse four-bar mechanism 3-2. Combined with the "second end of the first connecting segment 2c is hinged to the second hinge point 2a2 of the finger segment 2a" already explained in the above-mentioned forward four-bar mechanism 2-1, more specifically, the side of the finger segment 2a away from the mounting portion 1 is provided with a third hinge point 2a3; the side of the fingertip segment 3a close to the finger segment 2a is provided with a fourth hinge point 3a1 and a fifth hinge point 3a2, and the fourth hinge point 3a1 of the fingertip segment 3a is hinged to the third hinge point 2a3 of the finger segment 2a; the first end of the second connecting segment 3b is hinged to the first connecting segment 2c, and the second end of the second connecting segment 3b is hinged to the fifth hinge point 3a2 of the fingertip segment 3a.

[0041] For the reverse four-bar mechanism 3-2, the swing of the first connecting segment 2c relative to the finger segment 2a drives the fingertip segment 3a to swing in the opposite direction relative to the finger segment 2a. Combined with the required range of motion of the fingertip segment 3a to simulate a human finger, the reverse four-bar mechanism 3-2 can also be a double rocker.

[0042] See also Figure 1 and Figure 2 In addition, in order to better meet the bionics and aesthetics of the finger, the fingertip segment 3a can be installed with a second outer shell 3a3 of a corresponding shape. More specifically, the second outer shell 3a3 can be divided into two parts, which are respectively installed on the upper and lower sides of the finger segment 2a.

[0043] See also Figure 3 In some embodiments, the forward four-bar mechanism 2-1 formed by the mounting portion 1, the finger segment 2a, the driving segment 2b and the first connecting segment 2c is a parallelogram. More specifically, the two hinge points on the mounting portion 1 where the driving segment 2b and the finger segment 2a are hinged are connected (marked as the first connecting line 2-1a), and the first connecting line 2-1a can be horizontal. Correspondingly, the two hinge points on the first connecting end are connected (marked as the second connecting line 2-1b), and the second connecting line 2-1b is parallel to the first connecting line 2-1a and has the same length.

[0044] Thus, during the movement of the forward four-bar mechanism 2-1, the movement of the first connecting segment 2c relative to the mounting portion 1 is translation, without swinging. During the extension of the finger segment 2a, the angle between the finger segment 2a and the mounting portion 1 keeps increasing. Accordingly, since the first connecting segment 2c does not swing relative to the mounting portion 1, the angle between the first connecting segment 2c and the finger segment 2a (marked as angle 2-1c) keeps increasing. Conversely, during the retraction of the finger segment 2a, the angle between the finger segment 2a and the mounting portion 1 keeps decreasing. Accordingly, since the first connecting segment 2c does not swing relative to the mounting portion 1, the angle 2-1c keeps decreasing.

[0045] It can be seen that by designing the forward four-bar mechanism 2-1 to be a parallelogram, the following effect can be easily achieved: during the process of straightening and unfolding the finger segment 2a, the angle 1 2-1c is transformed in one direction.

[0046] See also Figure 3 and Figure 4, correspondingly, in the reverse four-bar mechanism 3-2, the swing of the first connecting segment 2c relative to the finger segment 2a (i.e., the change of the angle 1 2-1c) drives the fingertip segment 3a to swing in the opposite direction relative to the finger segment 2a. That is, during the straightening of the finger segment 2a, the angle 1 2-1c keeps increasing, the inner angle between the fingertip segment 3a and the finger segment 2a (marked as angle 2 3-2a) keeps decreasing, and the outer angle between the fingertip segment 3a and the finger segment 2a (marked as angle 3 3-2b, which is complementary to angle 2 3-2a) keeps increasing, which corresponds to the straightening of the fingertip segment 3a. On the contrary, during the retraction of the finger segment 2a, the angle 1 2-1c keeps decreasing, and the angle 3 3-2b keeps decreasing, which corresponds to the retraction of the fingertip segment 3a.

[0047] In some embodiments, the finger segment 2a is provided with a through slot 2a4 for the second connecting segment 3b to pass through. Accordingly, the first hinge point 2a1 for the first connecting segment 2c to be hinged and the second hinge point 2a2 for the mounting portion 1 to be hinged on the finger segment 2a are respectively located on both sides of the through slot 2a4.

[0048] In this way, the finger segment 2a, the first connecting segment 2c, the fingertip segment 3a and the second connecting segment 3b are more convenient to form the required reverse four-bar mechanism 3-2. The second connecting segment 3b is also in the finger segment 2a, similar to the ligament connecting the finger joint and the fingertip in the finger, which is more conducive to bionics and the aesthetic design of the mechanical finger.

[0049] In some embodiments, the hinge points of the driving section 2b and the second connecting section 3b on the first connecting section 2c overlap. That is, the corresponding hinge points of the three can be hinged together by a pin. Compared with hinged connection separately, the structure is simplified and assembly is more convenient.

[0050] See also Figure 2 , Figure 5 and Figure 6 The driving portion 4 is disposed on the mounting portion 1 , and drives the driving section 2 b to swing relative to the mounting portion 1 .

[0051] The driving unit 4 can use a rotary cylinder, a servo motor, etc. to directly drive the driving section 2b to swing. Preferably, the driving unit 4 can also include a linear drive 4a and a third connecting section 4b. The cylinder body of the linear drive 4a is fixedly connected to the mounting portion 1. One end of the third connecting section 4b is hinged to the telescopic rod of the linear drive 4a, and the other end is hinged to the driving section 2b to form a crank slider mechanism. That is, the driving section 2b is driven to rotate by the telescopic movement of the telescopic rod of the linear drive 4a. Of course, the driving section 2b is a rocker in the forward four-bar mechanism 2-1, and it does not need to be able to rotate a full circle. Accordingly, the stroke of the linear drive 4a is designed so that the driving section 2b only needs to swing a corresponding angle in the crank slider mechanism.

[0052] In this way, compared with using a rotary cylinder, a servo motor, etc. as the driving part 4, designing the driving part 4 into a crank slider mechanism has the following advantages: 1. Compared with directly controlling the swing angle position of the driving segment 2b, the swing angle of the driving segment 2b is controlled by the stroke of the linear driver 4a, which can more conveniently and simply debug the driving segment 2b and reach the required two extreme positions; 2. It is more in line with the bionics of the finger shape.

[0053] The linear drive 4a can be, but is not limited to, an electric cylinder, a pneumatic cylinder, an electric push rod, or other devices capable of generating linear motion. Preferably, the linear drive 4a uses a planetary roller screw electric cylinder. The planetary roller screw electric cylinder has better load, speed, force, and positioning accuracy, and is more suitable as a power source for the robot finger.

[0054] See also Figure 2 In some embodiments, the hinge points of the third connecting segment 4b and the first connecting segment 2c on the driving segment 2b coincide. Compared with hinged connection separately, the structure is simplified and the assembly is more convenient. Combined with the above-mentioned setting of "the hinge points of the driving segment 2b and the second connecting segment 3b on the first connecting segment 2c coincide", the first connecting segment 2c, the second connecting segment 3b, and the second connecting segment 3b are hinged together at the second end of the driving segment 2b.

[0055] It can be found that the knuckle unit 2 and the fingertip unit 3 are driven to move by the driving unit 4. During the assembly process, when the driving unit 4 is not installed, the knuckle unit 2 and the fingertip unit 3 can move on the mounting part 1 without a definite state.

[0056] See also Figure 2 and Figure 4 In some embodiments, the mechanical finger further comprises an elastic member 5. The elastic member 5 acts on the finger joint unit 2 and the finger tip unit 3, so that the finger tip segment 3a and the finger joint segment 2a tend to straighten.

[0057] The tendency to straighten here means that when the drive unit 4 is not installed, under the action of the elastic member 5, the knuckle unit 2 and the fingertip unit 3 remain in the straightened state. More specifically, a limit can be set in the above-mentioned forward four-bar mechanism 2-1 and the reverse four-bar mechanism 3-2, and under the action of the elastic member 5, the knuckle unit 2 and the fingertip unit 3 begin to move toward straightening until the limit is reached. For example, combined with the setting that "the knuckle segment 2a is provided with a through groove 2a4 for the second connecting segment 3b to pass through", when the second connecting segment 3b abuts against the inner wall above the through groove 2a4, the limit is reached. Correspondingly, after the drive unit 4 is installed, when the drive unit 4 drives the knuckle unit 2 and the fingertip unit 3 to retract, it will overcome the effect of the elastic member 5 on the fingertip segment 3a and the knuckle segment 2a.

[0058] The elastic member 5 can be a torsion spring, which is arranged at one of the hinge points of the knuckle unit 2 or the fingertip unit 3. Preferably, the elastic member 5 can also be a tension spring, one end of which is connected to the second connecting section 3b, and the other end is connected to the knuckle section 2a. More specifically, the second connecting section 3b and the knuckle section 2a are both provided with through holes for the tension spring to hook.

[0059] Thus, compared with using a torsion spring as the elastic member 5, designing the elastic member 5 as a tension spring is more convenient for installation and subsequent replacement, and is also more convenient to be covered by the first outer shell 2a5.

[0060] A bionic mechanical arm comprises the above-mentioned mechanical finger.

Claims

1. A mechanical finger, characterized in that: include: A mounting portion (1); The finger joint unit (2) comprises: a finger joint segment (2a) which forms a positive four-bar mechanism (2-1) with the mounting portion (1), a driving segment (2b) and a first connecting segment (2c); the finger joint segment (2a) is driven to swing in the same direction relative to the mounting portion (1) by the swing of the driving segment (2b) relative to the mounting portion (1); The fingertip unit (3) comprises: a fingertip segment (3a) and a second connecting segment (3b) which form a reverse four-bar mechanism (3-2) with a finger segment (2a) and a first connecting segment (2c); the fingertip segment (3a) is driven to swing in the reverse direction relative to the finger segment (2a) by the swing of the first connecting segment (2c) relative to the finger segment (2a); the finger segment (2a) is provided with a through-groove (2a4) for the second connecting segment (3b) to pass through; a first hinge point (2a1) on the finger segment (2a) for the first connecting segment (2c) to be hinged and a second hinge point (2a2) on the finger segment (2a) for the mounting portion (1) to be hinged are respectively located on both sides of the through-groove (2a4); The driving portion (4) is arranged on the mounting portion (1) and drives the driving section (2b) to swing relative to the mounting portion (1).

2. A mechanical finger according to claim 1, characterized in that: The driving part (4) comprises: a linear drive (4a) and a third connecting section (4b); the cylinder body of the linear drive (4a) is fixed to the mounting part (1); one end of the third connecting section (4b) is hinged to the telescopic rod of the linear drive (4a), and the other end is hinged to the driving section (2b), forming a crank slider mechanism.

3. A mechanical finger according to claim 1, characterized in that: Also includes: The elastic member (5) acts on the finger joint unit (2) and the finger tip unit (3), causing the finger tip segment (3a) and the finger joint segment (2a) to tend to straighten.

4. A mechanical finger according to claim 3, characterized in that: The elastic member (5) is a tension spring, one end of which is connected to the second connecting section (3b) and the other end of which is connected to the finger section (2a).

5. A mechanical finger according to claim 1, characterized in that: The positive four-bar mechanism (2-1) formed by the mounting portion (1), the finger segment (2a), the driving segment (2b) and the first connecting segment (2c) is in the shape of a parallelogram.

6. A mechanical finger according to claim 1, characterized in that: The hinge points of the driving section (2b) and the second connecting section (3b) on the first connecting section (2c) coincide with each other.

7. A mechanical finger according to claim 2, characterized in that: The hinge points of the third connecting section (4b) and the first connecting section (2c) on the driving section (2b) coincide with each other.

8. A mechanical finger according to claim 2, characterized in that: The linear drive (4a) is an electric cylinder.

9. A bionic manipulator, characterized in that: include: A mechanical finger as claimed in any one of claims 1 to 8.

Images