CN208084376U - A kind of decoupling mechanism of rope driving joint of mechanical arm - Google Patents

Abstract

The utility model discloses a decoupling mechanism for the joint of a rope-driven mechanical arm. In the decoupling mechanism, the driving wheel and the decoupling rope driving wheel are fixedly connected with the joint connecting rod, and the chute on the forearm of the mechanical arm restricts the sliding beam. Moving up and down, the diameter of the transition wheel that uses the rear joint to drive the rope is twice the diameter of the decoupling rope drive wheel, so that the displacement of the sliding beam when the current joint rotates is 1/2 of the end displacement of the rear joint drive rope. In this way, the displacement of the end of the driving rope of the rear joint caused by the rotation of the current joint and the displacement of the end of the driving rope of the rear joint caused by the up and down movement of the sliding beam cancel each other out. After the decoupling mechanism, there is no relative displacement between the driving rope and the joint connecting rod, so that the motion decoupling between the front and rear joints is realized. The decoupling mechanism of the utility model can work within the range of 0° to 300°, has a large working range, a simple and compact structure, increases the number of transition wheels and corresponding guide pulleys, and can decouple more rear joints.

Description

A Decoupling Mechanism for Rope-Driven Manipulator Joints

technical field

The utility model relates to the field of mechanical drive, in particular to a decoupling mechanism for a rope-driven mechanical arm joint.

Background technique

Most of the traditional manipulators install the drive motors directly at the joints, which makes the manipulators have a large volume and mass, a large moment of inertia, a complex structure, and a low load-to-weight ratio.

Rope drive technology uses a cable to transmit motion and force remotely to control the rotation of the joint, so that the entire drive unit can be installed on the base. Because the transmission rope is very light and the drive unit is external, the structure of the mechanical arm has been greatly simplified, and the mass, moment of inertia and volume have been greatly reduced, thus well solving the problems existing in the traditional mechanical arm. , but it also brings coupling problems between joints.

In the rope-driven tandem manipulator, since the rotation of the front-end joint will cause the winding amount of the driving rope of the rear-end joint passing through the front-end joint to change on the transition wheel, an additional motion will be generated for the rear-end joint, that is, the rotation of the two joints Movement is not independent.

At present, the decoupling methods for this kind of coupling mainly include active decoupling by using control algorithm and decoupling by designing decoupling mechanism. The complexity of algorithmic decoupling will increase greatly with the increase of joints. It is a rotary joint, and the kinematic coupling between the front and rear joints is nonlinear, so it is difficult to actively decouple through the control algorithm; there is no kinematic coupling with the lasso structure, but there is sliding friction between the driving rope and the lasso, not only The friction force is large, and there are nonlinear characteristics such as dead zone, gap, and hysteresis, so it is difficult to guarantee the control accuracy of the robotic arm.

Contents of the invention

In order to solve the problems existing in the existing decoupling structure, the utility model proposes a rope-driven decoupling mechanism to solve the motion coupling problem between the joints of the rope-driven series manipulator. The decoupling mechanism has a simple and reliable structure and a large working range. Less friction.

The technical scheme of the utility model is:

A decoupling mechanism for a rope-driven mechanical arm joint. The mechanical arm structure includes: a forearm, a rear arm, two positioning rods arranged side by side and fixedly connected to the rear arm, a pair of positioning rods fixedly connected to the forearm, side by side Arranged positioning rod two and positioning rod three and separate positioning rod four;

The decoupling mechanism includes a fifth guide pulley, a transition wheel, a decoupling assembly, a third guide pulley and a rear-end joint drive rope, the transition wheel includes at least transition wheel one, and the rear-end joint drive rope includes at least a rear-end joint drive The left section of the rope and the right section of the rear end joint drive the rope;

The guide pulley group five is composed of five guide pulleys set on the positioning rod one, and each positioning rod one is covered with at least one guide pulley five, and the five guide pulleys at least include a first guide pulley five and a second guide pulley five ;

The decoupling assembly sequentially includes from top to bottom: decoupling component 1, guide pulley set 4, decoupling component 2, guide pulley set 1;

The first decoupling part is composed of a driving wheel, a decoupling rope driving wheel 1 and a decoupling rope driving wheel 2, which are sequentially fixedly connected to the joint connecting rod;

The transition wheel is set on the joint connecting rod, and is between the decoupling rope driving wheel 1 and the decoupling rope driving wheel 2;

The guide pulley group 4 is composed of four guide pulleys set on the positioning rod 2, and each positioning rod 2 is covered with at least three guide pulleys 4, and the guide pulley 4 at least includes: a first guide pulley 4, a second guide pulley Pulley four, third guide pulley four, fourth guide pulley four, fifth guide pulley four and sixth guide pulley four;

The decoupling part 2 is composed of a displacement compensation device 1 and a displacement compensation device 2 arranged side by side, and the displacement compensation device 1 is composed of a fixed block 1, at least one guide pulley 2 and a fixed block 3 connected to the sliding beam 1 in sequence, The displacement compensating device 2 is composed of a fixed block 2, at least one guide pulley 2 and a fixed block 4 sequentially connected to the slide beam 2, and the guide pulley 2 at least includes a first guide pulley 2 and a second guide pulley 2;

The two slide grooves on the forearm are used to limit the corresponding sliding beam to move up and down;

The guide pulley group 1 is composed of a first guide pulley 1 and a second guide pulley 1 which are sequentially sleeved on the positioning rod 4;

The decoupling assembly also includes a decoupling rope, and the decoupling rope includes a decoupling rope 1 and a decoupling rope 2;

The upper section of the decoupling rope 1 bypasses the decoupling rope driving wheel 1, the first guide pulley 4 and the second guide pulley 4 and is fixed on the upper surfaces of the fixed block 1 and the fixed block 2 , the upper section of the decoupling rope 2 bypasses the decoupling rope driving wheel 2, the fifth guide pulley 4 and the sixth guide pulley 4 and is fixed on the fixed block 3 and the fixed block 4 On the surface, the lower section of the decoupling rope 1 bypasses the first guide pulley 1 and is fixed on the lower surface of the fixed block 1 and the fixed block 2, and the lower section of the decoupling rope 2 bypasses the second guide pulley. Guide pulley 1 is fixed on the lower surface of the fixed block 3 and the fixed block 4, so that the sliding beam 1 and the sliding beam 2 only bear the bending moment during operation, preventing the sliding beam 1 and sliding beam 2 from sideways turn;

The guide pulley group 3 is composed of guide pulleys set on the positioning rod 3, and each positioning rod 3 is covered with at least one guide pulley 3, and the guide pulley 3 includes at least a first guide pulley 3 and a second guide pulley 3 ;

The two positioning rods three are located outside the decoupling assembly, above the sliding beam one and the sliding beam two, one on each side;

The rear-end joint driving rope includes the left section of the rear-end joint driving rope and the right section of the rear-end joint driving rope. The lower end of the left section of the rear-end joint driving rope is connected with the rear-end joint driver, and then goes around the The first guide pulley three reverses 180°, and then goes around the first guide pulley two on the sliding beam one counterclockwise and reverses 180°, and then passes through the third guide pulley four and the transition wheel one upwards And the first guide pulley is connected with the driving wheel of the rear end joint five times;

The lower end of the right section of the rear-end joint drive rope is connected to the rear-end joint driver, and then goes up and counterclockwise around the second guide pulley three times and reverses 180°, then goes down and then clockwise around the two slide beams The second guide pulley 2 changes direction by 180°, and then passes upwardly through the fourth guide pulley 4, the transition wheel 1 and the second guide pulley 5, and then connects with the driving wheel of the rear end joint;

The current joint driving rope connects the driving wheel and the current joint driver.

Furthermore, the diameter of the wheel groove of the first transition wheel is twice the diameter of the wheel grooves of the first decoupling rope driving wheel and the second decoupling rope driving wheel.

The advantage of the utility model relative to the prior art is:

1. The decoupling joint of the rope-driven manipulator can realize the passive decoupling of the movement of the joint-driven rope. Since active decoupling is not required, the control algorithm of the manipulator is simplified;

2. The utility model adopts the transmission form of rope-pulley, and the friction force is small, which avoids the non-linear driving characteristics such as large friction, dead zone and hysteresis of the lasso drive;

3. The decoupling mechanism can work within the range of 0° to 300°, and has a large working range, and the increase in the number of transition wheels and corresponding guide pulleys can decouple the kinematic coupling between multiple joints, and the structure is simple and reliable.

Description of drawings

Fig. 1 is the overall structural diagram of the rope-driven mechanical arm decoupling mechanism of the present utility model;

Fig. 2 is a decoupling assembly diagram of the utility model;

Fig. 3 is a wiring diagram of the driving rope of the rear end joint of the present invention;

Fig. 4 is a structural diagram of the displacement compensation device of the present invention;

Fig. 5 is the wiring diagram of the current joint driving rope of the present utility model;

Fig. 6 is a diagram of the connection mode of the front and rear mechanical arms of the present invention;

Label name in the figure: 1-positioning rod one; 2-positioning rod two; 3-positioning rod three; 4-positioning rod four; 5-joint connecting rod; 61-decoupling rope drive wheel one; 62-decoupling rope drive Wheel two; 7-driving wheel; 81-transition wheel one; 91-sliding beam one; 92-sliding beam two; 101-fixed block one; 102-fixed block two; 103-fixed block three; 104-fixed block four; 11-rear-end joint drive rope; 111-left section of rear-end joint drive rope; 112-right section of rear-end joint drive rope; 121-first guide pulley one; 122-second guide pulley one; 131-first guide pulley Two; 132-the second guide pulley two; 141-the first guide pulley three; 142-the second guide pulley three; 151-the first guide pulley four; 152-the second guide pulley four; 153-the third guide pulley four; 154-fourth guide pulley; 155-fifth guide pulley four; 156-sixth guide pulley four; 161-first guide pulley five; 162-second guide pulley five; 15-current joint drive rope; 16-solution 17-decoupling rope 2; 18-forearm; 19-back arm; 20-chute; 201-current joint driver; 202-rear end joint driver.

Detailed ways

The accompanying drawings disclose non-restrictive structural schematic diagrams of the utility model involved and preferred implementations, and the technical solutions of the utility model will be described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, the decoupling mechanism of the rope-driven mechanical arm joint of the present utility model, the mechanical arm structure includes: a forearm 18, a rear arm 19, two positioning rods-1 arranged side by side and fixedly connected with the rear arm 19, and the forearm 18 fixedly connected positioning rods two 2 and positioning rods three 3 and independent positioning rods four 4 arranged side by side in groups of two;

The forearm 18 is connected to the rear arm 19 through the joint connecting rod 5, and when the joint connection 5 rotates, the rear arm 19 is driven to rotate, as shown in Figure 6;

The decoupling mechanism includes: guide pulley group five, transition wheel one 81, decoupling assembly, guide pulley group three and rear joint drive rope 11; A guide pulley 5 is set on a positioning rod 1, and the guide pulley 5 includes a first guide pulley 5 161 and a second guide pulley 5 162;

The decoupling assembly, as shown in Figure 2, includes from top to bottom: decoupling component 1, guide pulley set 4, decoupling component 2, guide pulley set 1;

The first decoupling part is composed of the driving wheel 7, the first decoupling rope driving wheel 61 and the second decoupling rope driving wheel 62, which are sequentially fixedly connected to the joint connecting rod 5;

Transition wheel one 81 is sleeved on the joint connecting rod 5, between decoupling rope driving wheel one 61 and decoupling rope driving wheel two 62, wherein, the wheel groove diameter of transition wheel 81 is the decoupling rope driving wheel one 61 and decoupling rope driving wheel two. 2 times the diameter of the groove of the decoupling rope driving wheel 2 62, see Figure 1;

Described guide pulley group 4 is made up of guide pulley 4 sets on positioning bar 2, and each positioning bar 2 sets three guide pulleys 4, and described guide pulley 4 comprises: first guide pulley 4 151, second guide pulley Four 152, the third guide pulley four 153, the fourth guide pulley four 154, the fifth guide pulley four 155 and the sixth guide pulley four 156;

The second decoupling component shown in Figure 4 is composed of a displacement compensation device 1 and a displacement compensation device 2 arranged side by side, and the displacement compensation device 1 consists of a fixed block 101, a first guide pulley 2 131 and a fixed block 3 103 It is sequentially connected to the sliding beam one 91, and the displacement compensating device two is composed of a fixed block two 102, a second guide pulley two 132 and a fixed block four 104 sequentially connected on the sliding beam two 92;

Two slide grooves 20 are processed on the forearm 18 for restricting the sliding beam one 91 and the sliding beam two 92 from moving up and down;

The set of guide pulleys is composed of a first guide pulley 121 and a second guide pulley 122 which are sequentially sleeved on the positioning rod 44;

Joint connecting rod 5, positioning rod two 2 and positioning rod four 4 are arranged sequentially from top to bottom, sliding beam one 91 and sliding beam two 92 are located between positioning rod two 2 and positioning rod four 4;

The decoupling assembly also includes a decoupling rope, and the decoupling rope includes a decoupling rope one 16 and a decoupling rope two 17;

The upper section of decoupling rope one 16 is fixed on the upper surface of fixed block one 101 and fixed block two 102 by decoupling rope drive wheel one 61, first guide pulley four 151 and second guide pulley four 152, decoupling rope two 117 The upper section of the decoupling rope drive wheel two 62, the fifth guide pulley four 155 and the sixth guide pulley four 156 are fixed on the upper surface of the fixed block three 103 and the fixed block four 104, and the lower section of the decoupling rope one 16 walks around the first A guide pulley one 121 is fixed on the lower surface of the fixed block one 101 and the second fixed block 102, and the lower section of the decoupling rope two 17 bypasses the second guide pulley one 122 and is fixed on the lower surface of the fixed block three 103 and the four fixed block 104, In this way, when working, the two sliding beams only bear the bending moment, which can prevent rollover;

The guide pulley group 3 is composed of three sets of guide pulleys on the positioning rod 3 3, and a guide pulley 3 is set on each positioning rod 3 3, and the guide pulley 3 includes a first guide pulley 3 141 and a second guide pulley 3 142 ;

Two positioning rods three 3 are located on the outside of the decoupling assembly, above the first sliding beam 91 and the second sliding beam 92, one on each side;

As shown in Figures 1 and 3, the rear-end joint driving rope 11 includes two parts, the left section 111 of the rear-end joint driving rope and the right section 112 of the rear-end joint driving rope. 202 connected, then go up clockwise around the first guide pulley three 141 and reverse 180°, then go around the first guide pulley two 131 on the sliding beam one 91 and reverse 180° counterclockwise, and then go up through the third guide Pulley 4 153, transition wheel 81 and first guide pulley 5 161 are connected with the driving wheel of the rear end joint;

The lower end of the rear-end joint driving rope right section 112 is connected with the rear-end joint driver 202, and then goes around the second guide pulley three 142 in an upward counterclockwise direction and reverses 180°, and then goes around the first sliding beam two 92 clockwise downwards. The second guide pulley two 132 changes direction by 180°, and then upwardly passes through the fourth guide pulley four 154, the transition wheel 81 and the second guide pulley five 162, and then connects with the drive wheel of the rear joint;

The current joint driving rope 15 connects the driving wheel 7 and the current joint driver 201 , as shown in FIG. 5 .

It should be pointed out that the utility model can decouple more joints at the rear end by adding transition wheels and corresponding guide pulleys. Within the spirit and principles of the present utility model, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present utility model.

Claims (2)

1. a kind of decoupling mechanism of rope driving joint of mechanical arm, which is characterized in that the mechanical arm configuration includes：Forearm （18）, postbrachium（19）, be arranged side by side and and postbrachium（19）Two locating rods one being fixedly connected（1）With forearm（18）It is fixedly connected In pairs, the locating rod two that is arranged side by side（2）With locating rod three（3）And individual locating rod four（4）；

The decoupling mechanism includes：Leading block group five, transition wheel one（81）, decoupled components, leading block group three and rear end close Section driving rope（11）；

The leading block group five is sleeved on locating rod one by leading block five（1）Upper composition, per a positioning rod one（1）Above cover one Leading block five, the leading block five include the first leading block five（161）With the second leading block five（162）；

The decoupled components include successively from top to bottom：Decouple component one, leading block group four, decoupling component two and leading block Group one；

The decoupling component one is by driving wheel（7）, decoupling rope driving wheel one（61）With decoupling rope driving wheel two（62）Successively It is fixedly connected on joint link lever（5）Upper composition；

Transition wheel one（81）It is sleeved on joint link lever（5）On, and in decoupling rope driving wheel one（61）With decoupling rope driving wheel Two（62）Between；

The leading block group four is sleeved on locating rod two by leading block four（2）Upper composition, per a positioning rod two（2）Above cover three Leading block four, the leading block four include：First leading block four（151）, the second leading block four（152）, third leads To pulley four（153）, the 4th leading block four（154）, the 5th leading block four（155）With the 6th leading block four（156）；

The decoupling component two is made of the displacement compensation device one and displacement compensation device two being arranged side by side, the bit shift compensation Device one is by fixed block one（101）, the first leading block two（131）With fixed block three（103）It is connected to skid beam one in turn（91） Upper composition, the displacement compensation device two is by fixed block two（102）, the second leading block two（132）With fixed block four（104）According to It is secondary to be connected to skid beam two（92）Upper composition；

Forearm（18）On be machined with two sliding slots（20）It moves up and down for limiting corresponding skid beam；

The leading block group one is by the first leading block one（121）With the second leading block one（122）It is sequentially sleeved in locating rod Four（4）Upper composition；

The decoupled components further include decoupling rope, and the decoupling rope includes decoupling rope one（16）With decoupling rope two （17）；

Decouple rope one（16）Epimere around decoupling rope driving wheel one（61）, the first leading block four（151）It is led with second To pulley four（152）It is fixed on fixed block one（101）With fixed block two（102）Upper surface, decouple rope two（17）Epimere Around decoupling rope driving wheel two（62）, the 5th leading block four（155）With the 6th leading block four（156）It is fixed on fixed block Three（103）With fixed block four（104）Upper surface, decouple rope one（16）Hypomere bypass the first leading block one（121）Gu It is scheduled on fixed block one（101）With fixed block two（102）Lower surface, decouple rope two（17）Hypomere bypass the second leading block One（122）It is fixed on fixed block three（103）With fixed block four（104）Lower surface；

The leading block group three is sleeved on locating rod three by leading block three（3）Upper composition, per a positioning rod three（3）Above cover one Leading block three, the leading block three include the first leading block three（141）With the second leading block three（142）；

Two locating rods three（3）On the outside of the decoupled components, skid beam one（91）With skid beam two（92）Top, both sides each one；

Rear end joint drive rope（11）Including left section of rear end joint drive rope（111）With right section of rear end joint drive rope （112）；Left section of rear end joint drive rope（111）Lower end and rear end joint driver（202）It is connected, later upwards clockwise Around the first leading block three（141）180 ° of commutation bypasses skid beam one counterclockwise still further below（91）On the first leading block two （131）180 ° of commutation, is then passed upwardly through third leading block four（153）, transition wheel one（81）And first leading block five （161）It is connected afterwards with the driving wheel in rear end joint；

Right section of rear end joint drive rope（112）Lower end and rear end joint driver（202）It is connected, it is first counterclockwise upwards later Around the second leading block three（142）180 ° of commutation bypasses downwards skid beam two clockwise again（92）On the second leading block two （132）180 ° of commutation, is then passed upwardly through the 4th leading block four（154）, transition wheel one（81）And second leading block five （162）It is connected afterwards with the driving wheel in rear end joint；

Current joint drives rope（15）Connect driving wheel（7）With current joint driver（201）.

2. a kind of decoupling mechanism of rope driving joint of mechanical arm according to claim 1, which is characterized in that transition wheel one （81）Race diameter be decoupling rope driving wheel one（61）With decoupling rope driving wheel two（62）2 times of race diameter.