CN113001516B - Over-constrained amphibious robot - Google Patents
Over-constrained amphibious robot Download PDFInfo
- Publication number
- CN113001516B CN113001516B CN202110265797.8A CN202110265797A CN113001516B CN 113001516 B CN113001516 B CN 113001516B CN 202110265797 A CN202110265797 A CN 202110265797A CN 113001516 B CN113001516 B CN 113001516B
- Authority
- CN
- China
- Prior art keywords
- over
- output shaft
- constrained
- joint
- rod
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J17/00—Joints
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/0009—Constructional details, e.g. manipulator supports, bases
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D57/00—Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track
- B62D57/02—Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members
- B62D57/032—Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid
Abstract
The invention discloses an over-constrained amphibious robot which comprises a robot body and a plurality of over-constrained moving devices, wherein each over-constrained moving device comprises a coaxial driving device and an over-constrained connecting rod mechanism, and each coaxial driving device comprises an outer driver, an inner driver, an outer output shaft and an inner output shaft. The over-constrained moving device provides driving force for the over-constrained amphibious robot, has the potential of crawling on land or under water, can be used for other article operations such as grabbing or carrying articles, drives the over-constrained connecting rod mechanism to perform smart three-dimensional movement through two drivers, realizes smart three-dimensional space movement under the condition of avoiding the addition of the drivers, performs all-direction multi-terrain movement including forward, transverse and turning, and is beneficial to controlling the weight and cost of the robot.
Description
Technical Field
The invention relates to the technical field of robots, in particular to an over-constrained amphibious robot.
Background
The existing robot generally adopts a decoupling mechanism to realize the design of a multi-joint multi-degree-of-freedom robot, namely, each degree of freedom of the robot is independently provided with an independent driver, and the independent drivers on a plurality of connecting rods and the connecting rod connection forming mechanism are used for realizing multi-joint movement, for example, a single-degree-of-freedom robot mainly comprises a driver and a connecting rod connected to the driver, a double-degree-of-freedom robot mainly comprises two rods and independent drivers on each connecting rod, a three-degree-of-freedom robot mainly comprises three rods and independent drivers on each rod, and the like.
On the basis, in order to meet the requirements of the robot on various aspects such as motion sensitivity, dexterity and the like in the interaction process with the external environment, a plurality of connecting rods are often combined to form a plurality of specially designed mechanisms, the actual arrangement positions driven by the robot are transferred to other parts (usually with larger inertia, such as approaching to the center of gravity, a base, a chassis and the like) from the motion ends of the degrees of freedom, and thus the maneuvering performance and the whole machine cost of the robot can be still maintained under the condition of not remarkably increasing the load of the driver.
Currently, there are mainly three robot configurations, namely a chain configuration, a parallel configuration and a compound configuration.
Under the chain configuration, each connecting rod of the robot is connected in sequence to form an open loop single chain, so that the robot has good mechanism decoupling characteristic, a driver is often required to be independently arranged at each connecting rod or the free degree end, the number of the free degrees of the mechanism is consistent with that of the drivers, and common examples include a general multi-joint industrial mechanical arm.
In parallel configuration, the robot is generally driven by a specially designed mechanism, at least one closed loop is formed between two banks, the drivers are arranged in a concentrated way at a position close to the center of gravity, the base and the chassis, each driver still drives one degree of freedom, and the number of degrees of freedom of the mechanism is consistent with that of the drivers. The most common mechanisms are planar link mechanisms and variants thereof (including belt drives, cam mechanisms and the like), which are more common in some high-speed planar motion mechanical arms and some foot robots, and also some spherical link mechanisms and variants thereof (the axes of the rotating shafts intersect at a point in space), which are more common in some surgical robots.
The compound configuration is a robot which adopts a chain type mechanism and a parallel mechanism at the same time, and often has higher number of degrees of freedom (4-7), the parallel configuration is adopted in the first 3 degrees of freedom to reduce the moment of inertia of the whole machine, the chain type configuration is adopted in the latter several degrees of freedom to independently drive, and the robot is more common in heavy industrial mechanical arms and toy mechanical arms.
In the prior art, the number of the degrees of freedom of the mechanism, the number of the drivers and the degree of freedom of the actually realized space motion are always in equal relation, and one great advantage of the design is that theoretical analysis, mechanism design and control are generally simpler and more direct in realization, and the design has rich and mature practical application cases. The main problem is that when the robot is interacted with complex environments, a higher degree of freedom is needed, so that a correspondingly higher number of drivers is needed, the weight, the cost and the like of the whole robot are higher, and the robot is particularly obvious on a foot-type robot or a multi-arm and multi-finger robot. For example, a four-foot robot using a two-degree-of-freedom parallel mechanism generally requires 8 drivers (Stanford dog, ghost minitar, etc.), while a four-foot robot using a three-degree-of-freedom compound configuration requires 12 drivers (Boston Dynamics Spot Mini, MIT chetah, etc.).
At present, a relatively common and widely applied motion device is a connecting rod type mechanical leg, which is a mechanical leg based on a planar connecting rod mechanism, such as Stanford dog and SpaceBok, and a planar four-bar mechanism with two degrees of freedom is adopted as a leg mechanism. However, the working range of the two-degree-of-freedom planar mechanical leg can only be a plane, and the final movement space of the robot is a three-dimensional space, so that some special movements (such as lateral movement along the body, smooth in-situ rotation and the like) cannot be realized, and the steering can only be performed by means of the differential speed of the two-side gait. For robots with two-degree-of-freedom planar legs, it is difficult to change the direction of movement, and it is often possible to achieve a relatively large turning speed radius, limiting its agility in narrow environments. While a three degree-of-freedom robot leg typically requires an additional actuator attached to the base of the two degree-of-freedom leg to achieve high speed maneuver, introducing an additional actuator presents new challenges to managing the total weight and cost of the robot.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention provides the over-constrained amphibious robot which performs smart three-dimensional movement under the action of the over-constrained movement device by crawling the over-constrained movement device on land or under water.
The invention discloses an over-constrained amphibious robot, which comprises a robot body and a plurality of over-constrained movement devices arranged on the robot body, wherein the over-constrained movement devices comprise: the coaxial driving device comprises an outer driver, an inner driver, an outer output shaft and an inner output shaft, wherein the outer driver drives the outer output shaft, the inner driver drives the inner output shaft, and the inner output shaft and the outer output shaft are coaxially arranged; the inner output shaft is connected with a first driving rod of the over-constraint link mechanism, and the outer output shaft is connected with a second driving rod of the over-constraint link mechanism.
Preferably, the tail end of the over-constraint link mechanism is provided with an extension rod, and the extension rod of the front-side over-constraint link mechanism is provided with a mechanical finger.
Preferably, the invention further comprises a depth camera arranged at the front end of the machine body, and a plurality of over-constrained motion devices are symmetrically distributed on two sides of the machine body.
Preferably, the outer driver is connected with the outer output shaft in a collimation driving mode, and the reduction ratio of the output shaft of the outer driver to the outer output shaft is 1:5-1:10; the inner driver is connected with the inner output shaft in a collimation driving mode, and the reduction ratio of the output shaft of the inner driver to the inner output shaft is 1:5-1:10.
Preferably, the over-constrained linkage mechanism comprises one of the following mechanisms: all overconstrained mechanisms such as Bennett mechanism, goldberg mechanism, myard mechanism, extended Myard mechanism, double-Goldberg mechanism, waldron's Hybrid mechanism, yu & Baker's Syncopated mechanism, mavroidis & Roth's 6R mechanism, dietmaier's 6R mechanism, briard mechanism, altmann's 6R mechanism, wohlhart's Hybrid 6R mechanism, etc.
Preferably, the connecting rod of the Bennett mechanism further comprises a first driven rod and a second driven rod, a first joint is formed at the upper ends of the first driving rod and the second driving rod, a second joint is formed between the first driving rod and the first driven rod, a third joint is formed between the second driving rod and the second driven rod, a fourth joint is formed at the hinge joint of the first driven rod and the second driven rod, and the expression of the Bennett mechanism is as follows:
wherein a is ij Denoted as the link between the i-joint and the j-joint, alpha ij Representation a ij The torsion angles of a and b are the lengths of the connecting rods, alpha and beta are the torsion angles, R i Indicating the joint offset, i being indicated as joint;
the relationship of the joint angles is as follows:
wherein θ i The joint angle is expressed as a joint rotation angle and is used for expressing the included angle of two connecting rods on the joint.
Preferably, the coaxial driving device further comprises a mounting plate and a supporting frame, the outer driver and the inner driver are mounted on the mounting plate, a base is arranged on one side of the mounting plate, the outer output shaft is rotatably mounted on the base, a first outer synchronous pulley is mounted on the output shaft of the outer driver, and the first outer synchronous pulley is connected with a second outer synchronous pulley mounted on the outer output shaft through a synchronous belt;
a first inner synchronous pulley is arranged on an output shaft of the inner driver and is connected with a second inner synchronous pulley arranged on the outer output shaft through a synchronous belt;
the mounting plate is mounted on the fuselage, and the outer driver and the inner driver are mounted on the same side of the mounting plate.
Preferably, the connecting rod comprises a positioning pipe and hinge assemblies arranged at two ends of the positioning pipe, the hinge assemblies comprise mounting rods and hinge joints arranged on the mounting rods, and the hinge joints are arranged at one ends of the positioning pipe through the mounting rods.
Preferably, the connecting rod is divided into a first part and a second part, the first part and the second part are respectively provided with a connecting ring, and one end of the connecting column is arranged on the connecting ring through a screw.
Compared with the prior art, the invention has the beneficial effects that: the over-constrained moving device provides driving force for the over-constrained amphibious robot, crawls on land or under water, can also perform other operations such as grabbing or carrying objects, and drives the over-constrained connecting rod mechanism to perform smart three-dimensional movement through two drivers, so that the flexible three-dimensional movement is realized under the condition of avoiding the addition of the drivers, forward, transverse and turning movements are performed, and the weight and cost of the robot are controlled.
Drawings
FIG. 1 is a schematic view of the structure of an over-constrained amphibious robot of the present invention;
FIG. 2 is a schematic diagram of the structure of a mechanical finger;
FIG. 3 is a schematic view of the installation of a depth camera;
FIG. 4 is a schematic view of the structure of the over-constrained exercise device;
fig. 5 is a schematic structural view of the coaxial drive device;
FIG. 6 is a schematic diagram of dynamics analysis of an overconstrained linkage
FIG. 7 is a schematic diagram of an equivalent open-chain analysis of an overconstrained linkage;
FIG. 8 is a schematic diagram of the kinetic analysis of the Bennett mechanism;
FIG. 9 is a schematic diagram of the kinetic analysis of the Myard institution;
FIG. 10 is a schematic diagram of the kinetic analysis of the Extended Myard mechanism;
FIG. 11 is a schematic diagram of the detection and workspace of the Bennett mechanism;
FIG. 12 is a schematic view of three motion trajectories of a mechanical leg;
FIG. 13 is a diagram of center of gravity detection for three movements;
FIG. 14 is a schematic view of the construction of an over-constrained robot;
FIG. 15 is a schematic view of a second over-constrained exercise device;
fig. 16 is a schematic view of a third over-constrained exercise device.
The marks in the figure: 1, overconstraining a connecting rod mechanism, 2, an inner output shaft; 3, an outer output shaft; 4, mounting plates; 5 an external driver; 6, an outer driver output shaft; 7, a synchronous belt; 8, a first outer synchronous pulley; 9 supporting frames; 10 a base; a second inner synchronous pulley 11, a coaxial driving device 12, a second outer synchronous pulley 13, an inner driver 15, an inner driver output shaft 16, a first inner synchronous pulley 18, and a bearing 19; 21 a first driving rod, 22 a second driving rod, 23 a first driven rod, 24 a second driven rod, 25 ends; 31 first part, 32 second part, 33 connecting ring, 34 connecting post, 35 screw, 36 hinge screw, 41 first joint, 42 second joint, 43 third joint, 44 fourth joint, 45 expansionThe device comprises a tight pulley, a 46 second fixing frame, a 51 connecting piece, a 52 machine body, a 53 fixing plate, a 54 depth camera, a 55 over-constrained motion device, a 56 mounting frame, a 57 control box, a 61 positioning tube, a 62 hinging assembly, a 63 hinging head, a 72 mechanical finger, a 73 rod, a 74 propeller, a 75 driver, a 76 hoop piece, a 77 second connecting piece, a 78 extending rod, a 79 illuminating lamp and a 80 detection sonar, and a z 1 Drive shaft, z 2 First intermediate shaft, z 4 Second intermediate shaft, z 3 A distal shaft.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention is described in further detail below with reference to the attached drawing figures:
an over-constrained amphibious robot, as shown in fig. 1, 3 and 4, comprises a robot body 21 and a plurality of over-constrained movement means 55 provided on the body; the overconstrained motion device 55 comprises a coaxial driving device 12 and an overconstrained linkage mechanism 1, the coaxial driving device 12 comprises an outer driver 5, an inner driver 15, an outer output shaft 3 and an inner output shaft 2, the outer driver 5 drives the outer output shaft 3, the inner driver 15 drives the inner output shaft 2, and the inner output shaft 2 and the outer output shaft 3 are coaxially arranged; one end of the inner output shaft 2 is connected with a first driving rod 21 of the over-constraint link mechanism 1, and one end of the outer output shaft 3 is connected with a second driving rod 22 of the over-constraint link mechanism 1.
The over-constrained moving device provides driving force for the over-constrained amphibious robot, has the potential of crawling on land or under water, can also perform other operations such as grabbing or carrying objects, and the over-constrained moving device 55 drives the over-constrained link mechanism 1 to perform smart three-dimensional movement through two drivers, so that the smart three-dimensional space movement is realized under the condition of avoiding the addition of the drivers, and the all-directional multi-terrain movement including forward, transverse and turning is performed, so that the weight and cost of mechanical legs and the robot are controlled. The two driving rods of the over-constraint connecting rod move under the action of the drivers respectively, and three-dimensional movement is generated under the constraint of each connecting rod, namely, smart three-dimensional movement is generated under the two drivers, so that the use of the drivers is reduced. The conventional over-constrained link mechanism only has one degree of freedom and has one fixed base link, in the invention, the fixed base link is adjusted to be two driving rods coaxially arranged, and the driving rods are driven by the drivers to move, so that the tail end 25 of the over-constrained link mechanism 1 moves in three-dimensional space, namely, the single degree of freedom is converted into two degrees of freedom by the two drivers, and the amphibious robot moves in two degrees of freedom.
As shown in fig. 2 and 3, the end of the over-constrained linkage 1 may be provided with an extension rod 78 on which the mechanical finger 72 is provided on the front side of the over-constrained linkage. Extension bar 78 is used to raise the center of gravity of the over-constrained exercise device to increase exercise space; the fingers 72 are used to grasp the article. The front end of the body 52 may also be mounted with a depth camera 54, an illumination lamp 79 and a detection sonar 80. As shown in fig. 12, a plurality of over-constrained moving devices are symmetrically distributed on two sides of the machine body, the rear over-constrained moving device walks as a mechanical leg, the front over-constrained moving device operates as a mechanical arm, but not limited thereto, as in fig. 12, four over-constrained moving devices can be used for crawling an amphibious robot, the number of over-constrained moving devices 55 can be set according to actual needs, for example, 2-6 over-constrained moving devices are used as mechanical legs, and 2 over-constrained moving devices are used as mechanical arms.
As shown in fig. 2, an underwater outer limb can be mounted on the over-constrained amphibious robot, the underwater outer limb comprises a driver 75, a propeller 74 and a connecting assembly, the connecting assembly comprises a positioning rod 73 and a hoop member 76, the left end and the right end of the positioning rod 73 are respectively connected with the hoop member 76, the driver 75 is mounted on one side of the hoop member 76, and the output end of the driver 75 is connected with the outer side wall of the propeller 74 through a second connecting member 77. In one embodiment, the connection 77 employs a connection flange. The hoop member 76 has a fixing function for fixing the driver 75, and the positioning rod 73 is connected to the driver 75 symmetrically arranged on the left and right sides. The left and right drivers 75 are respectively used for independently controlling the pushing direction of the pusher 74, and the positioning rod 73 is used for connecting the two drivers 75 on one hand and keeping the axes of the output shafts of the drivers 75 coincident on the other hand, so as to keep the relative positions of the two pushers.
In a specific embodiment, as shown in fig. 5, the coaxial driving device 12 further comprises a mounting plate 4 and a supporting frame 9, the outer driver 5 and the inner driver 15 are mounted on the mounting plate 4, a base 10 is arranged on one side of the mounting plate 4, the outer output shaft 3 is rotatably mounted on the base 10, a first outer synchronous pulley 8 is mounted on the outer driver output shaft 6, and the first outer synchronous pulley 8 is connected with a second outer synchronous pulley 13 mounted on the outer output shaft 3 through a synchronous belt 7, so that transmission between the outer driver 5 and the outer output shaft 3 is realized; the first inner synchronous pulley 18 is arranged on the inner driver output shaft 16, and the first inner synchronous pulley 18 is connected with the second inner synchronous pulley 11 arranged on the inner output shaft 2 through the synchronous belt 7, so that the transmission of the inner driver 15 and the inner output shaft 2 is realized; one side of the first outer synchronous pulley 8 is provided with a supporting frame 9. Wherein, bearing 19 can be arranged between the base 10 and the outer output shaft 3, the outer output shaft 3 and the inner output shaft 2, the mounting plate 4 is arranged on the machine body 52, and the outer driver 5 and the inner driver 15 are arranged on the same side of the mounting plate 4.
The supporting frame 9 is used for protecting the motor and the power transmission component. The mounting plate 4 and the connecting rod can be made of carbon fiber materials, the joints of the over-constraint connecting rod mechanism 1 can be made of aluminum alloy or stainless steel materials, and the outer driver 5 and the inner driver 15 are arranged on the same side of the mounting plate 4, such as the inner side, so that the drivers can be effectively protected, and meanwhile, the drivers do not move along with the movement of the over-constraint connecting rod mechanism, and the rotational inertia of the robot unit is effectively reduced.
The overconstrained linkage 1 may be assembled in a modular manner: the aluminum alloy hinge is arranged at two ends of the carbon fiber connecting rod tube, and the aluminum alloy hinge are rotatably connected through a shaft, but the implementation is not limited to the above.
The outer driver is connected with the outer output shaft in a collimation driving mode, and the reduction ratio of the output shaft of the outer driver to the outer output shaft is 1:5-1:10; the inner driver is connected with the inner output shaft in a collimation driving mode, and the reduction ratio of the output shaft of the inner driver to the inner output shaft is 1:5-1:10. through the mode of collimation drive, lower reduction ratio is adopted, when the overconstrained link mechanism interferes or collides, the current of the driver changes greatly, and the interference or collision is judged through the change of the current, so that the use of partial sensors, such as torsion sensing force, can be reduced.
In a specific test, the invention tests the Bennett mechanism, the Goldberg mechanism, the Myard mechanism, the Extended Myard mechanism and the Double-Goldberg mechanism, and tests and describes the movement performance of each mechanism, but the invention is not limited to the following mechanism, and the over-constraint link mechanism can also be one of the following mechanisms: all overconstrained mechanisms such as Waldron's Hybrid mechanism, yu & Baker's Syncopated mechanism, mavroidis & Roth's 6R mechanism, dietmaier's 6R mechanism, briard mechanism, altmann's 6R mechanism, wohlhart's Hybrid 6R mechanism, and the like.
As shown in fig. 6 and 7, in the kinetic analysis, the relationship of the outer drive, the inner drive, and the end of the over-constrained linkage can be expressed as:
φ i ＝h i (θ i )＝H i (q 1 ，q 2 ) (1)
wherein phi is i Equivalent open-chain rotation angle, θ, expressed as joint i i Expressed as joint angle, q 1 Expressed as the external drive speed, q 2 Expressed as internal drive speed, h i () Representing the function of the joint rotation angle and the equivalent open-chain rotation angle, H i () Represented as a function of the row to open chain rotation angle and drive speed.
Equivalent open-chain analysis treats the closed-loop links in the over-constrained linkage mechanism as serial open-chains, the motion on each joint is treated as virtual electric motion, and the equivalent joint angle phi i Through the actual joint angle theta i To define, in a kinematic analysis,from the angle q of the drive i Through the equation 7, the robot leg can be subjected to kinematics and dynamics analysis by a classical modeling method.
And the expression of the end movement speed is:
where V denotes the end movement speed, J denotes Jacobian (Jacobian), si denotes the coordinates of the rotation axis of the joint i at the initial position, which is the position of the link of the restraint mechanism when it is on the same plane, and J denotes the total number of joints between the end axis and the drive shaft.
Example 1
As shown in fig. 8, the left graph is a schematic diagram of the kinetic analysis of the Bennett mechanism, and the right graph is a schematic diagram of the equivalent open-chain analysis. The Bennett mechanism comprises four connecting rods and four joints, wherein two driving rods are respectively connected with two output shafts, a first joint 41 is formed at the hinge joint of the driving rods, and the driving shaft of the first joint 41 is z 1 A second joint 42 and a third joint 43 are formed between the driving rod and the driven rod, and the first intermediate shaft of the second joint 42 is z 2 The second intermediate axis of the third joint 43 is z 4 The junction of the two driven bars forms a fourth joint 44 with a terminal axis z 3 The expression of the Bennett mechanism is:
wherein a is ij Denoted as the link between the i-joint and the j-joint, alpha ij Representation a ij The torsion angles of a and b are the lengths of the connecting rods, alpha and beta are the torsion angles, R i Indicating the joint offset, i being indicated as joint; for example, a 12 Represented as a link between a first joint and a second joint; a, a 34 Represented as a connecting rod between a third joint and a fourth joint, a 23 Representing a second jointA connecting rod between the third joints, a 41 Denoted as link, alpha between fourth joint and first joint 12 Representation a 12 Is a of the torsion angle of (a) 34 Representation a 34 Is a of the torsion angle of (a) 23 Representation a 23 Is a of the torsion angle of (a) 41 Representation a 41 The first joint 41 serves as a driving joint, the fourth joint 44 serves as a distal end, and the relationship of the joint angles is:
wherein θ i The joint angle is expressed as a joint rotation angle and is used for expressing the included angle of two connecting rods on the joint. When α=β=0/pi, the four side bars form a plane, and the time bannit ratio is 0 as the initial position.
In FIG. 8, x s And z s Expressed as coordinate axes, σ is expressed as the joint angle (z s And z 1 For a constant value), the Bennett mechanism has two degrees of freedom, where α=β=0/pi, and for a 270 degree value, the Bennett mechanism has a planar two-degree-of-freedom parallel leg. However, σ may also be a variable, in which case the Bennett mechanism has three degrees of freedom, i.e. the degree of freedom of the hip joint on the coronal plane (first joint angle) is increased, σ may be driven by the inner and outer drivers.
The expression of the tip movement speed is:
the expression of the end torque is:
τ＝J T F S (14)
where τ is denoted as tip torque, F S Expressed as joint moment, J T Represented as jacobian matrix.
Fig. 11 and 12 are test charts of an overconstrained exercise device used as a mechanical leg, and evaluation of indexes of the mechanical leg and a working room was performed. Fig. 11 shows the projection of the motion profile of the mechanical leg in the Y-Z plane. Fig. 12 shows the trajectories of three movement modes of a four-foot robot provided with an over-constrained movement device of the present invention, respectively: forward travel path, lateral travel path, and turn path, the upper drawing is a plane projection drawing, and the lower drawing is a perspective drawing. The result shows that the single-foot walking robot with the over-constrained exercise device can walk forward. Even if each mechanical leg has only two drivers, the quadruped robot can walk sideways, and the gait behavior is similar to that of a crab.
In addition, simulation results show that the quadruped robot can turn on site, and the omnibearing capacity can be realized without additional advanced control or additional driving. From fig. 13, the center of gravity change in three movement modes of the quadruped amphibious robot is shown, the center of gravity height fluctuates to a certain extent in front jogging and lateral jogging, the maximum is 9.2mm in the vertical direction measurement, the maximum is 10.3mm, and the maximum is only 4mm in turning.
In one specific design, as shown in fig. 4, 15 and 16, the connecting rod of the Bennett mechanism includes a first driving rod 21, a second driving rod 22, a first driven rod 23 and a second driven rod 24, and the first driving rod 21, the second driving rod 22, the first driven rod 23 and the second driven rod 24 are hinged in sequence to form a spatial single closed loop mechanism.
The coaxial driving device 12 can also comprise a mounting plate 4 and a supporting frame 9, wherein the outer driver 5 and the inner driver 15 are mounted on the mounting plate 4, a base 10 is arranged on one side of the mounting plate 4, the outer output shaft 3 is rotatably mounted on the base 10, a first outer synchronous pulley 8 is mounted on the outer driver output shaft 6, and the first outer synchronous pulley 8 is connected with a second outer synchronous pulley 13 mounted on the outer output shaft 3 through a synchronous belt 7, so that the transmission of the outer driver 5 and the outer output shaft 3 is realized; the first inner synchronous pulley 18 is arranged on the inner driver output shaft 16, and the first inner synchronous pulley 18 is connected with the second inner synchronous pulley 11 arranged on the inner output shaft 2 through the synchronous belt 7, so that the transmission of the inner driver 15 and the inner output shaft 2 is realized; one side of the first outer synchronous pulley 8 is provided with a supporting frame 9. Wherein bearings 19 may be provided between the base 10 and the outer output shaft 3, the outer output shaft 3 and the inner output shaft 2.
The supporting frame 9 is used for protecting the motor and the power transmission component. The mounting plate 4 and the connecting rod can be made of carbon fiber materials, the joints of the over-constraint connecting rod mechanism 1 can be made of aluminum alloy or stainless steel materials, the outer driver 5 and the inner driver 15 are arranged on the same side of the mounting plate 4, the drivers can be effectively protected, meanwhile, the drivers do not move along with the movement of the over-constraint connecting rod mechanism, and the rotational inertia of the robot unit is effectively reduced.
The connecting rod can adopt a modularized assembly mode: as shown in fig. 1, the hinge assembly 62 is installed at two ends of the positioning tube 61, the hinge assembly 62 comprises a mounting rod and a hinge joint 63 installed on the mounting rod, the mounting rod is embedded into one end of the positioning tube and is fixed, the angle of the mounting rod and the positioning tube is adjusted, the initial angle of the hinge joint 63 and the joint is adjusted, the hinge joint can be set according to the installation mode of the connecting rod, for example, the hinge joint 63 at the upper end of the driving rod is provided with a mounting hole matched with the output shaft, and the hinge hole of the hinge joint at the lower end of the driving rod is matched with the hinge joint at the upper end of the first driven rod through a screw to realize hinge, but the hinge joint is not limited to the above.
Fig. 15 is a schematic structural view of a second over-constrained exercise device, in which the design of the connecting rod is different, and the connecting rod is designed into a first portion 31 and a second portion 32 for a more flexible assembly structure, the first portion 31 and the second portion 32 are respectively provided with a connecting ring 33, and one end of a connecting post 34 is mounted on the connecting ring 33 by a screw 35, so as to facilitate adjustment of the initial rotation angle of the joint. The driving rod and the driven rod are hinged by a hinge screw 36.
Fig. 16 is a schematic structural view of a third over-constrained exercise device, in which a link is provided with a torsion angle, and the initial angle of the joint is adjusted by adjusting the torsion angle. The first joint 41 is formed at the upper ends of the first driving rod 21 and the second driving rod 22, the second joint 42 is formed between the first driving rod 21 and the first driven rod 23, the third joint 43 is formed between the second driving rod 22 and the second driven rod 24, the fourth joint 44 is formed at the hinge position of the first driven rod 23 and the second driven rod 24, and the lower end of the driven rod is used as the tail end 25 of the over-constraint link mechanism 1. One side of the synchronous belt 7 can be provided with a tension wheel 45, and the driver is fixed on the mounting plate 4 through a second fixing bracket 46.
The outer driver drives the outer output shaft in a collimation driving mode, and the reduction ratio of the outer driver to the outer output shaft is 1:5-1:10, preferably 1:10; the inner driver drives the inner output shaft in a collimation driving mode, and the reduction ratio of the inner driver to the inner output shaft is 1:5-1:10, preferably 1:10. through the mode of collimation drive, lower reduction ratio is adopted, when the overconstrained link mechanism interferes or collides, the current of the driver changes greatly, and the interference or collision is judged through the change of the current, so that the use of partial sensors, such as torsion sensing force, can be reduced.
Example 2
Unlike in the case of example 1,
five revolute joints are arranged in the Myard5R mechanism, as shown in FIG. 9, a left graph is a kinetic analysis schematic diagram, a right graph is an equivalent open-chain analysis schematic diagram, wherein two crossed joints are arranged at the tail end of the Myard5R mechanism, and the expression of the Myard5R mechanism is as follows:
joint rotation angle theta on outer output shaft 1 Expressed as:
θ 1 ＝f(q 1 ，q 2 )＝π-(q 2 -q 1 ). (22)
the expression of the tip movement speed is:
although the 5R overconstraining mechanism has a relatively complex closed equation, the equivalent open-chain kinematic analysis method significantly reduces the complexity of the kinematic derivation and derives the kinematic formula of the machine leg for the Myard5R case.
Example 3
As shown in fig. 10, the left graph is a kinetic analysis schematic diagram of the Extended Myard mechanism, the right graph is an equivalent open-chain analysis schematic diagram, six rotational joints and four connecting rods are provided in the Extended Myard 6R mechanism, two joints which are symmetrically arranged are provided at the connection positions of the active connecting rod and the passive connecting rod, and the expression is as follows:
joint rotation angle theta on outer output shaft 1 Expressed as:
θ 1 ＝f(q 1 ，q 2 )＝π+q 2 -q 1 (32)
the expression of the tip movement speed is:
a four-foot over-constrained amphibious robot is shown in fig. 1, but is not limited thereto.
As shown in fig. 14, the over-constrained locomotion device may include a low-gravity-center robot locomotion device adapted for walking of a multi-legged robot and a high-gravity-center robot locomotion device, which is mainly used for walking of a human-like body, may be formed by installing an extension bar at the end of the low-gravity-center over-constrained locomotion device, thereby improving the working space of the high-gravity-center over-constrained locomotion device. The robot body 52 can be provided with the connecting piece 51, the overconstrained motion device is arranged on the connecting piece 51 through the mounting plate 4 to form a robot, and the overconstrained motion device can be used as a mechanical leg, a mechanical arm or a mechanical finger to reconstruct a new robot.
1-4 groups of over-constrained motion devices, namely 2-8 over-constrained motion devices, can be adopted and are uniformly distributed on two sides of the machine body, and the over-constrained amphibious robot can be designed into various forms, such as an insect robot, a bipedal robot and a bipedal animal robot; quadruped, crab-shaped robots, lobster robots, and humanoid robots.
Four-legged robot is equipped with four over-constrained motion devices 55 of symmetric distribution in fuselage 52 both sides, and as shown in fig. 1, fuselage 52 can splice through fixed plate 53 and form, is equipped with control box 57 and mini computer on the fuselage 52, and mini computer installs on the mounting bracket 56 of fuselage upside, and the fuselage front side is equipped with depth camera 54, realizes omnidirectional motion through eight drivers.
The lobster robot is composed of four groups of low-gravity center moving devices, one group is used as a manipulator arm, and the three groups are used as manipulator mechanical legs to move.
The humanoid robot is composed of a group of high-gravity-center mechanical arms and a group of high-gravity-center mechanical legs, and the outer ends of the mechanical arms can be provided with mechanical fingers.
The bipedal robot is provided with a group of mechanical legs with high gravity center at the lower side of the robot body. The crab-shaped robot is composed of six overconstrained motion devices symmetrically distributed on the left and right sides of the body.
Two drives are used per movement device for three-dimensional movement to reduce weight and cost.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. An over-constrained amphibious robot is characterized by comprising a robot body and a plurality of over-constrained movement devices arranged on the robot body,
the overconstrained motion device comprises: a coaxial driving device and an over-constraint link mechanism,
the coaxial driving device comprises an outer driver, an inner driver, an outer output shaft and an inner output shaft,
the outer driver drives the outer output shaft, the inner driver drives the inner output shaft,
the inner output shaft and the outer output shaft are coaxially arranged;
the inner output shaft is connected with a first driving rod of the over-constraint link mechanism, and the outer output shaft is connected with a second driving rod of the over-constraint link mechanism;
the over-constraint link mechanism further comprises a first driven rod and a second driven rod, wherein the first driving rod, the second driving rod, the first driven rod and the second driven rod are sequentially hinged to form a space single closed-loop mechanism;
wherein, the hinge joint of the first driving rod and the second driving rod and the inner output shaft forms a first joint; a second joint is formed between the first driving rod and the first driven rod; a third joint is formed between the second driving rod and the second driven rod, and a fourth joint is formed between the first driven rod and the second driven rod;
the axes of the pivot axes of the first, second, third and fourth joints are non-parallel;
the first driving rod, the second driving rod, the first driven rod and the second driven rod all comprise: a first part, a second part, a connection ring for rotationally connecting the first part and the second part, a connection post for fixing the connection ring to adjust a torsion angle between the first part and the second part and an initial rotation angle of a corresponding joint;
and the second part of the first driving rod is hinged with the second part of the first driven rod; the second part of the second driving rod is hinged with the first part of the second driven rod;
the over-constrained amphibious robot further comprises: a depth camera mounted at a front end of the body; and a plurality of overconstrained motion devices are symmetrically distributed on both sides of the body.
2. The over-constrained amphibious robot of claim 1, wherein the end of the over-constrained linkage is provided with an extension rod, and the extension rod of the front over-constrained linkage is provided with a mechanical finger.
3. The over-constrained amphibious robot of claim 1, wherein the outer driver is connected with the outer output shaft in a collimation driving manner, and a reduction ratio of the output shaft of the outer driver to the outer output shaft is 1:5-1:10;
the inner driver is connected with the inner output shaft in a collimation driving mode, and the reduction ratio of the output shaft of the inner driver to the inner output shaft is 1:5-1:10.
4. the over-constrained amphibious robot of claim 1, wherein the relationship of the outer drive, inner drive and over-constrained linkage ends is:
φ i ＝h i (θ i )＝H i (q 1 ,q 2 ) (1)
wherein phi is i Equivalent open-chain rotation angle, θ, expressed as joint i i Expressed as joint angle, q 1 Expressed as the external drive speed, q 2 Expressed as internal drive speed, h i (θ i ) Representing the function of the joint rotation angle and the equivalent open-chain rotation angle, H i (q 1 ,q 2 ) Represented as a function of row-to-open chain rotation angle and drive speed;
the expression of the end movement speed is:
wherein V represents the terminal movement speed, J represents a Jacobian matrix, si represents the coordinates of the rotation axis of the joint i at the initial position, the initial position is the position of the connecting rod of the over-constraint mechanism on the same plane, and J represents the total number of joints between the terminal axis and the driving shaft.
5. The over-constrained amphibious robot of claim 1, wherein the over-constrained linkage comprises one of: bennett mechanism, goldberg mechanism, myard mechanism, extended Myard mechanism, double-Goldberg mechanism, waldron's Hybrid mechanism, yu & Baker's Syncopated mechanism, mavroidis & Roth's 6R mechanism, dietmaier's 6R mechanism, briard mechanism, altmann's 6R mechanism, and Wohlhart's Hybrid 6R mechanism.
6. The over-constrained amphibious robot of claim 5, wherein the expression of Bennett's mechanism is:
a 12 ＝a 34 ＝a,a 23 ＝a 41 ＝b,
α 12 ＝a 34 ＝a,a 23 ＝α 41 ＝β,
R i ＝0 (11)
wherein a is ij Represented as a connecting rod between the i-joint and the j-joint, a ij Representation a ij The torsion angles of a and b are the lengths of the connecting rods, alpha and beta are the torsion angles, R i Indicating the joint offset, i being indicated as joint;
the relationship of the joint angles is as follows:
wherein θ i The joint angle is expressed as a joint rotation angle and is used for expressing the included angle of two connecting rods on the joint.
7. The over-constrained amphibious robot according to claim 6, wherein the coaxial driving device further comprises a mounting plate and a supporting frame, the outer driver and the inner driver are mounted on the mounting plate, a base is arranged on one side of the mounting plate, the outer output shaft is rotatably mounted on the base, a first outer synchronous pulley is mounted on the output shaft of the outer driver, and the first outer synchronous pulley is connected with a second outer synchronous pulley mounted on the outer output shaft through a synchronous belt;
a first inner synchronous pulley is arranged on an output shaft of the inner driver and is connected with a second inner synchronous pulley arranged on the outer output shaft through a synchronous belt;
the mounting plate is mounted on the fuselage, and the outer driver and the inner driver are mounted on the same side of the mounting plate.
8. The over-constrained amphibious robot of claim 1, wherein one end of the connecting post is mounted on the connecting ring by a screw.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110265797.8A CN113001516B (en) | 2021-03-11 | 2021-03-11 | Over-constrained amphibious robot |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110265797.8A CN113001516B (en) | 2021-03-11 | 2021-03-11 | Over-constrained amphibious robot |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113001516A CN113001516A (en) | 2021-06-22 |
| CN113001516B true CN113001516B (en) | 2023-04-25 |
Family
ID=76405252
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110265797.8A Active CN113001516B (en) | 2021-03-11 | 2021-03-11 | Over-constrained amphibious robot |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113001516B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106904226B (en) * | 2017-03-10 | 2022-12-23 | 杭州宇树科技有限公司 | Leg power system structure of electric drive quadruped robot |
| CN110104088B (en) * | 2019-04-28 | 2020-12-29 | 北京理工大学 | Robot mouse leg and foot structure based on micro-steering engine |
| CN110217311B (en) * | 2019-05-28 | 2024-01-26 | 广东省智能制造研究所 | Agile four-foot robot based on coaxial parallel mechanism |
| CN110217314A (en) * | 2019-07-03 | 2019-09-10 | 广东仙童智能机器人科技有限公司 | A kind of robot |
| CN111924019B (en) * | 2020-07-29 | 2023-06-09 | 北京科技大学 | Eight-free-dial brushless motor driven quadruped robot |
-
2021
- 2021-03-11 CN CN202110265797.8A patent/CN113001516B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113001516A (en) | 2021-06-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| He et al. | Mechanism, actuation, perception, and control of highly dynamic multilegged robots: A review | |
| Carbone et al. | Legged robotic systems | |
| US7339340B2 (en) | Control system and related method for multi-limbed, multi-legged robot | |
| JP2001150371A (en) | Robot and revolute joint device for robot | |
| Kuehn et al. | System design and testing of the hominid robot charlie | |
| WO2017087986A1 (en) | Non-anthropomorphic bipedal robotic system | |
| US20220203518A1 (en) | Articulated multi-link robotic tail systems and methods | |
| Gim et al. | Design of a serial-parallel hybrid leg for a humanoid robot | |
| Li et al. | Type synthesis of a family of novel parallel leg mechanisms driven by a 3-DOF drive system | |
| CN113001516B (en) | Over-constrained amphibious robot | |
| Hirose et al. | A proposal for cooperative robot" Gunryu" composed of autonomous segments | |
| CN113001517B (en) | Overconstrained motion device and robot | |
| Feng et al. | An overconstrained robotic leg with coaxial quasi-direct drives for omni-directional ground mobility | |
| Wang et al. | A new bionic structure of inspection robot for high voltage transmission line | |
| JP2003266358A (en) | Robot device and revolute joint shaft driving device | |
| Xu et al. | Design and experiments of a human-leg-inspired omnidirectional robotic leg | |
| Cordes et al. | On the design of a four-legged walking machine | |
| Peng et al. | Whole body collaborative planning method for legged locomotion manipulation system in operation process | |
| CN113022822B (en) | Underwater outer limb and application thereof | |
| JP3212491B2 (en) | Direct teaching control device | |
| Chung et al. | On the design and development of a quadruped robot platform | |
| Tiejun et al. | The development of a mobile humanoid robot with varying joint stiffness waist | |
| Xu et al. | Trajectory planning of jumping over obstacles for hopping robot | |
| US11787045B2 (en) | Robot with an inverse kinematics (IK)-based controller for retargeting input motions | |
| Fukuda et al. | Multilocomotion robot: novel concept, mechanism, and control of bio-inspired robot |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |