CN106361475B - A kind of overall bionic knee joint of tensioning - Google Patents

Abstract

The invention discloses a tension integral bionic knee joint, which belongs to the technical field of mechanical bionic engineering and comprises a first rigid compression unit, a cable unit and a second rigid compression unit. The first rigid compression unit is composed of a main body of the first rigid compression unit, a first support rod, a second support rod, a third support rod and a fourth support rod. The cable unit is composed of the first bionic cruciate ligament, the second bionic cruciate ligament, the bionic collateral ligament, the first cable and the second cable. The tensegrity bionic joint is used in conjunction with the bionic ligament and other cables to realize joint movement in the sagittal plane while avoiding the existence of a rigid connection axis in the middle of the joint, so that there is no friction between rigid bodies during the joint movement , wear and tear, improve the service life of joints. At the same time, the cable unit is made of rubber material, which has strong elasticity, and can absorb certain impact loads during work to improve stability.

Description

A Tensile Whole Bionic Knee Joint

technical field

The invention relates to the technical field of mechanical bionic engineering, in particular to a bionic knee joint based on a tensegrity integral structure applicable to the fields of robots, prosthetics and the like.

Background technique

Research work on robots worldwide has been widely carried out, but at present almost all robot joints (hip joints, knee joints and ankle joints, etc.) are simplified and designed as hinged connections. Since the robot joints are often subjected to various types of loads such as tension and compression, shearing, bending and torsion during motion, driving and complex control are required to maintain the stability of the joint motion in real time. At the same time, since the hinge connection is mostly rigid , There is inevitably friction and impact between rigid bodies. Studies have shown that these may be important reasons for the complexity of the motion control system of this type of robot and the low energy efficiency. There is no good solution yet.

The limbs of animals have a fine skeletal-muscular system, which is divided into the skeletal system and the muscular system. The former includes bones, cartilage, ligaments, etc., and the latter is mainly composed of muscles and tendons. Among them, multiple ligaments bind the bones to form joints and ensure the stability of the joints; the active contraction of muscles generates muscle force and transmits the force to the connected bones through tendons, thereby generating joint motion of the bones. From the perspective of biomechanics, it can be seen that the bones and cartilage in the skeletal-muscular system are mainly subjected to compressive loads, while ligaments, muscles, tendons and other tissues are mainly subjected to tensile forces. Therefore, the animal leg skeletal-muscular system can be regarded as an organism composed of stretched ligaments, muscles, tendon tissues and compressed bones with spatial topology characteristics, and is a special "tension" existing in organisms. pull the overall structure".

The concept of tensegrity structure was first proposed by American structural engineer Fuller in the 1940s, which refers to a self-balancing space-stable structure formed by discontinuous compression members contained in continuous tension members. After that, many structural mechanics researchers explored and researched the theory and technology of this new structure, and it has been successfully applied in the field of structural engineering. In recent years, with the in-depth crossover and integration of multiple disciplines, the idea of tensegrity has attracted the attention of researchers in the fields of biomechanics and bionic robotics worldwide, and its connotation has been further expanded. Research at Ghent University in Belgium shows that a tensegrity-based snake robot can maintain its gait motion stability using only linear control. NASA Ames Research Center has developed tensegrity soft robots for deep space exploration.

It can be seen that the tensegrity structure has become one of the most active research directions in the field of biomechanics and robotics, which is closely related to the flexibility, self-stress and self-balance characteristics of the structural system itself. And these characteristics may be closely related to the energy-saving motion of the robot. Flexibility can enable the leg joints of the robot to calmly cope with foot-ground impact loads during motion, reducing the joint drive burden, and at the same time, flexibility replaces rigid connections to eliminate the gap between rigid bodies. friction and reduce energy consumption. The self-balancing properties ensure the stability of the leg joints during the gait cycle.

Taking a comprehensive view of the research status of the above-mentioned robotic joints and tensegrity structures, and the excellent biomechanical structural characteristics of animal joints, there is an urgent need for a tensegrity bionic knee joint.

Contents of the invention

The purpose of the present invention is to provide a tensegrity integral bionic knee joint in order to solve the problems of the rigid hinge joints used in existing robots, such as easy friction, joint failure due to wear, high energy consumption for maintaining joint stability, and poor impact absorption ability. . The test shows that the bionic knee joint based on the tensegrity structure can well complete the swing of the joint in the sagittal plane. Due to the design of the tensegrity structure, the overall composition of the joint includes tension-only components and rigidity-only components. The compression member does not have the problem of friction and impact between rigid elements. At the same time, the tensegrity structure itself has self-stability, which can reduce the energy consumption caused by maintaining the stability of the joints of the robot applying the present invention.

The invention comprises a first rigid pressure unit, a cable unit and a second rigid pressure unit.

The first rigid compression unit is composed of a main body of the first rigid compression unit, a first support rod, a second support rod, a third support rod and a fourth support rod. Wherein, two sets of symmetrically distributed first support rods are fixedly connected to the main body of the first rigid compression unit through four sets of first screws. Two sets of symmetrically distributed second support rods are fixedly connected to the main body of the first rigid compression unit through four sets of second screws. A pair of symmetrically distributed third support rods are fixed between the two groups of first support rods by two pairs of fifth screws, so as to enhance the overall support rigidity. Four evenly distributed fourth support rods are respectively fixedly connected with the first support rods through sixth screws.

The cable unit is composed of a first bionic cruciate ligament, a second bionic cruciate ligament, a bionic collateral ligament, a first cable and a second cable. Among them, the first bionic cruciate ligament and the second bionic cruciate ligament imitate the arrangement characteristics of the human knee cruciate ligament, and the first bionic cruciate ligament and the second bionic cruciate ligament pass through two sets of ninth screws respectively to form a cross The cross-shaped distribution is between the main body of the first rigid pressure unit and the main body of the second rigid pressure unit. The bionic collateral ligaments used in pairs are symmetrically arranged on both sides of the main body of the first rigid compression unit and the main body of the second rigid compression unit, and are fixed to the boss of the first rigid compression unit and the second rigid compression unit by third screws on the boss. The two ends of the first cable used in pairs and symmetrically distributed are fixed on the end of the second support rod by the fourth screw, and the middle part of the first cable is fixed on the second rigid support rod by the tenth screw used in pairs. Press the top of the unit body. Also used in pairs and distributed symmetrically, the two ends of the second cable are fixed on the end of the fourth support rod by the seventh screw, and the middle part of the second cable is fixed on the second rigid rod by the eighth screw used in pairs. The inner side of the boss of the pressure unit.

Working process and principle of the present invention:

In the specific use process, the first rigid compression unit, the cable unit and the second rigid compression unit constitute a bionic joint based on tension, and the use of the cable unit in the middle of the joint avoids the joint function while realizing the joint function. The existence of the rigid connection shaft in the middle of the joint makes the friction and wear between the rigid bodies not exist when the joint moves. The use of the first bionic cruciate ligament and the second bionic cruciate ligament simulates the cruciate ligament of the human knee joint to limit the range of joint swing. The bionic collateral ligament used in pairs simulates the role of the peroneal collateral ligament and tibial collateral ligament in the human knee joint, avoiding excessive swing of the joint along the non-motion plane, the antagonism of the first bionic cruciate ligament and the second bionic cruciate ligament, The antagonism between the bionic collateral ligament and the first cable and the second cable enables the sagittal plane movement function of the tension joint to be realized. Here, the bionic collateral ligament plays the role of inhibiting the deviation movement of the first rigid compression unit and the second rigid compression unit, while the first cable and the second cable play the role of inhibiting the movement of the first rigid compression unit and the second rigid compression unit. The effect of approaching, using the first cable and the second cable at the same time can improve the stability of the joint movement.

Beneficial effects of the present invention:

1. By simulating the structure of the cruciate ligament, peroneal collateral ligament and tibial collateral ligament in the human knee joint, the present invention realizes the design of the tensed whole knee joint, and at the same time limits the range of motion of the bionic joint.

2. The present invention can well realize the swing of the joint in the sagittal plane through the tensioned overall structure, and at the same time, there is no friction, wear and impact between rigid bodies when the joint is moving, which improves the stability and life of the joint .

3. The present invention has a certain degree of self-stability. If applied to robot joints, it can reduce the energy consumed by the robot to maintain the stability of its own joints, and improve the overall energy efficiency of the body.

Description of drawings

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a front view of the present invention.

Fig. 3 is a partial view of the bionic cruciate ligament of the present invention.

Fig. 4 is a left view of the present invention.

Among them: 1-the first rigid compression unit; 11-the main body of the first rigid compression unit; 12-the first support rod; 13-the first screw; 14-the second screw; 15-the third screw; 16-the first Rigid compression unit boss; 17-second support rod; 18-fourth screw; 19-third support rod; 120-fifth screw; 121-sixth screw; 122-fourth support rod; 123-seventh Screw; 2-cable unit; 21-first bionic cruciate ligament; 22-second bionic cruciate ligament; 23-bionic collateral ligament; 24-first cable; 25-second cable; 3-second Rigid compression unit; 31-eighth screw; 32-boss of the second rigid compression unit; 33-ninth screw; 34-main body of the second rigid compression unit; 35-tenth screw.

detailed description

Referring to FIG. 1 , FIG. 2 , FIG. 3 and FIG. 4 , this embodiment includes a first rigid compression unit 1 , a cable unit 2 and a second rigid compression unit 3 .

The first rigid compression unit 1 is composed of the first rigid compression unit main body 11, the first support rod 12, the second support rod 17, the third support rod 19, and the fourth support rod 122. Two groups of symmetrically distributed The first support rod 12 is fixedly connected to the main body 11 of the first rigid compression unit through four sets of first screws 13; On the unit main body 11; a pair of symmetrically distributed third support rods 19 are fixed between the two groups of first support rods 12 by two pairs of fifth screws 120 to enhance the overall support rigidity; four evenly distributed fourth support rods 122 are fixedly connected with the first support rod 12 through sixth screws 121 respectively.

The cable unit 2 is composed of a first bionic cruciate ligament 21, a second bionic cruciate ligament 22, a bionic collateral ligament 23, a first cable 24 and a second cable 25, the first bionic cruciate ligament 21 and The second bionic cruciate ligament 22 imitates the arrangement characteristics of the human knee cruciate ligament. The first bionic cruciate ligament 21 and the second bionic cruciate ligament 22 pass through two sets of ninth screws 33 respectively, and are distributed in the shape of a cross at the bottom. Between a rigid compression unit main body 11 and a second rigid compression unit main body 34; paired bionic collateral ligaments 23 are symmetrically arranged on both sides of the first rigid compression unit main body 11 and the second rigid compression unit main body 34, The third screw 15 is fixed on the boss 16 of the first rigid pressure unit and the boss 32 of the second rigid pressure unit; The ends of the two support rods 17, and the middle part of the first cable 24 is fixed on the top of the second rigid compression unit main body 34 by the tenth screw 35 used in pairs; the second cable used in pairs and symmetrically distributed 25 Both ends are fixed on the end of the fourth support rod 122 by the seventh screw 123, and the middle part of the second cable 25 is fixed on the inner side of the boss 32 of the second rigid compression unit by the eighth screw 31 used in pairs .

The material of the first bionic cruciate ligament 21 , the second bionic cruciate ligament 22 , the bionic collateral ligament 23 , the first cable 24 and the second cable 25 can be rubber.

The working process and principle of this embodiment:

During the use of the present invention, the first rigid compression unit 1, the cable unit 2, and the second rigid compression unit 3 constitute a bionic joint based on a tensioned whole, and the use of the cable unit 2 in the middle of the joint realizes the joint function At the same time, the existence of the rigid connection shaft in the middle of the joint is avoided, so that there is no friction between the rigid bodies when the joint moves. The use of the first bionic cruciate ligament 21 and the second bionic cruciate ligament 22 simulates the cruciate ligament of the human knee joint to limit the range of joint swing. The bionic collateral ligaments 23 used in pairs simulate the functions of the peroneal collateral ligament and the tibial collateral ligament in the human knee joint, avoiding excessive swing of the joint along the non-motion plane, the first bionic cruciate ligament 21 and the second bionic cruciate ligament 22 Antagonism, the antagonism between the bionic collateral ligament 23 and the first cable 24 and the second cable 25 enables the sagittal plane movement function of the tension joint to be realized. Here, the bionic collateral ligament 23 plays the role of restraining the departure movement of the first rigid compression unit 1 and the second rigid compression unit 3 , while the first cable 24 and the second cable 25 play the role of inhibiting the movement of the first rigid compression unit 1 and the second rigid compression unit 3 . The effect that the second rigid pressure unit 3 approaches. Simultaneous use of the first cable 24 and the second cable 25 can improve the stability of the joint movement.

Claims (2)

1. a kind of overall bionic knee joint of tensioning, it is characterised in that：Comprising the first rigid pressure receiving means (1), drag-line unit (2) and Second rigid pressure receiving means (3)；

Described first rigid pressure receiving means (1) by the first rigid pressure receiving means main body (11), first support bar (12), second Strut (17), the 3rd support bar (19), the 4th support bar (122) composition；Two groups of symmetrical first support bars (12) pass through Four group of first screw (13) is connected on the first rigid pressure receiving means main body (11)；Two groups of symmetrical second support bars (17) It is connected in by four group of second screw (14) on the first rigid pressure receiving means main body (11)；A pair of the 3rd symmetrical support bars (19) it is fixed on by two pair of the 5th screw (120) between two groups of first support bars (12)；Four equally distributed 4th support bars (122) it is connected respectively by the 6th screw (121) and first support bar (12)；

Described drag-line unit (2) is by the first bionical right-angled intersection ligament (21), the second bionical right-angled intersection ligament (22), bionical Ligamena collateralia (23), the first drag-line (24) and the second drag-line (25) composition；First bionical right-angled intersection ligament (21) and second bionical Right-angled intersection ligament (22) imitates the arrangement feature of human knee joint's right-angled intersection ligament, the first bionical right-angled intersection ligament (21) With the second bionical right-angled intersection ligament (22) respectively by two group of the 9th screw (33), the first rigidity is distributed in into cross-shaped Between pressure receiving means main body (11) and the second rigid pressure receiving means main body (34)；The symmetrical cloth of bionical ligamena collateralia (23) used in pairs Put in the first rigid pressure receiving means main body (11) and second rigid pressure receiving means main body (34) both sides, it is fixed by the 3rd screw (15) In on the first rigid pressure receiving means boss (16) and the second rigid pressure receiving means boss (32)；Use in pairs and symmetrical the One drag-line (24) two ends are fixed on the end of second support bar (17) by the 4th screw (18), and by use in pairs the tenth Screw (35) makes the top that the second rigid pressure receiving means main body (34) is fixed in the middle part of the first drag-line (24)；Use in pairs and right Claim the second drag-line (25) two ends of distribution to be fixed on the end of the 4th support bar (122) by the 7th screw (123), pass through simultaneously The 8th screw (31) used in pairs makes to be fixed on the interior of the second rigid pressure receiving means boss (32) in the middle part of the second drag-line (25) Side.

2. the overall bionic knee joint of a kind of tensioning according to claim 1, it is characterised in that：The first described bionical cross Ligamentaum cruciatum (21), the second bionical right-angled intersection ligament (22), bionical ligamena collateralia (23), the first drag-line (24) and the second drag-line (25) material is rubber.