CN209050744U

CN209050744U - A kind of flexible cooperation mechanical arm

Info

Publication number: CN209050744U
Application number: CN201821938800.8U
Authority: CN
Inventors: 唐悦
Original assignee: Beijing Mita Network Technology Co Ltd
Current assignee: Shanghai Mita Network Technology Co ltd
Priority date: 2018-11-22
Filing date: 2018-11-22
Publication date: 2019-07-02
Anticipated expiration: 2028-11-22

Abstract

The utility model belongs to cooperation mechanical arm technical field, disclose a kind of flexible mechanical arm and its control method of cooperating, including pedestal, mechanical arm body and execute fixture, the bottom end of mechanical arm body is connect with base rotation, the top that fixture is set to mechanical arm body is executed, is provided with control panel and bottom steering engine in pedestal；Mechanical arm body includes the first horn and the second horn of rotation connection；Executing fixture includes multiple flexible gripping fingers, executes fixture by performing steering wheel and drives clamping.The utility model reduces the labyrinth of tradition cooperation mechanical arm, reduce the requirement to driving force, the utility model uses execution fixture flexible, it can be grabbed from multiple angles, by the way that strain readings are introduced into position and speed control ring, it realizes steering engine and actively offsets arm vibration, improve the control precision of mechanical arm；By way of carrying out current detecting to steering engine, it is achieved at low cost collision detection and dragging teaching.Therefore it is suitble to promote the use of.

Description

A kind of flexible cooperation mechanical arm

Technical field

The utility model belongs to cooperation mechanical arm technical field, and in particular to a kind of flexible cooperation mechanical arm.

Background technique

Current mechanical arm can be divided into two major classes: need secure isolation zone traditional industry mechanical arm and can be with people The cooperation mechanical arm of coexistence.Mechanical arm be a multiple-input and multiple-output, nonlinearity, close coupling complication system.Solely because of it Special operating flexibility, is used widely in fields such as industry assembling, safety anti-explosives；With the deep research and development of mechanical arm, Its structure and precision are greatly improved, and are not only applied in current field, are also expanded to many direct auxiliary people The technical field operated, or even can partially replace the work of people.

Cooperation mechanical arm is wanted to coexist safely with people, and user can be allowed easily to be programmed, and needs to realize collision inspection It surveys and the dragging big function of teaching two.In order to improve the kinematic accuracy of mechanical arm, current cooperation mechanical arm be designed to volume compared with Material for huge structure, and use high rigidity is made, and is reduced with this because material properties lead to the deformation of mechanical arm itself；This Sample the result is that cause mechanical arm quality higher, and since material is very rigid, once mechanical arm collides with people, lead to people Injured probability is higher.Therefore, current cooperation mechanical arm manufacturer is in the modules such as the control algolithm of mechanical arm and emergency brake A large amount of investments are improved, and make mechanical arm not occur surprisingly leading to collision out of control as far as possible, such way is properly termed as proactive security measures. If proactive security measures are by adequately research and development and test, it is ensured that the safety of mechanical arm, but have research and development difficulty high, it grinds The disadvantage for sending out period length, it is higher to also result in product cost.This, which just allows cooperation mechanical arm to actually enter consumer market, becomes tired It is difficult.

In industrial circle, current cooperation mechanical arm is mainly used for automation production flow line, and price is generally 100,000 To 200,000 RMB.So high price is very limited the application field of cooperation mechanical arm, however consumer market pair Cooperation mechanical arm has vast potential demand, such as does to the nursing of old man, for muscular atrophy patient enhancing action edge, family Meal auxiliary etc..This kind of demand does not need cooperation mechanical arm and reaches industrial circle application standard, however this block market still lacks at present The product of weary strong low cost exists.

Therefore, in this field in order to improve the proactive security measures dynamic role of cooperation mechanical arm, while it is mechanical to reduce cooperation The cost of arm needs to propose more reasonable technical solution, the technical issues of to better solve instantly.

Utility model content

The utility model provides a kind of flexible cooperation mechanical arm, it is intended to which the structure for simplifying cooperation mechanical arm reduces its matter Amount and volume improve the structure of the execution end of cooperation mechanical arm, keep the cooperation of cooperation mechanical arm and people more smooth, cooperation peace Full performance greatly improves, while substantially reducing the cost of cooperation mechanical arm.

In order to realize said effect, the technology employed by the present utility model is

A kind of flexible cooperation mechanical arm, including pedestal, mechanical arm body and execution fixture, the bottom end of the machinery arm body It is connect with base rotation, executes the top that fixture is set to mechanical arm body.Specifically, being provided with control panel in the pedestal With bottom steering engine, bottom steering engine is for driving mechanical arm to horizontally rotate；The mechanical arm body includes the first of rotation connection Horn and the second horn, the first horn and the second horn after horn servo driving in vertical direction by relatively rotating；Described holds Row fixture includes multiple flexible gripping fingers, executes fixture by performing steering wheel and drives clamping；It the bottom steering engine, horn steering engine and holds Row steering engine is electrically connected to control panel, and is respectively connected with current sensor between each steering engine and control panel.

The utility model executes fixture by pedestal and mechanical arm body driving and realizes clamping operation, and pedestal realizes mechanical arm Rotation in the horizontal direction, the horn steering engine in mechanical arm body realize the movement on vertical direction, execute fixture realize it is flexible Clamping, avoids and damages during clamping, while mechanical arm whole progress collision detection and concussion during the motion Eliminate, avoid the expansion of injury, improve mechanical arm with people's collaborative and safety.

Further, the first horn and the second horn drive mechanical arm by horn steering engine, in conjunction with mechanical arm sheet The structure of body, the quantity of horn steering engine and position setting can influence the state of entire mechanical arm, carry out to above-mentioned technical proposal Optimization, the horn steering engine include the first steering engine, the second steering engine and third steering engine, and first steering engine is set to the first horn Front end at, second steering engine and third steering engine are respectively arranged at the front end and end of the second horn.This prioritization scheme will The six degree of freedom structure of tradition cooperation mechanical arm is simplified, and is reduced the overall volume of mechanical arm, is reduced mechanical arm itself Weight, alleviate the burden of steering engine, make the reduction of mechanical arm service requirement, practicability is stronger.

Further, the mechanical arm body and pedestal relative level rotate, and mechanical arm body is realized by its front end With the rotation connection of pedestal, guarantee other freedom degrees of mechanical arm body it is unaffected in the case where, to above-mentioned technical proposal into Row optimization, the front end of first horn are provided with the first cabinet, and the output axis connection of the first cabinet and bottom steering engine is simultaneously same Axis rotation；First steering engine is located in the first cabinet, and the output shaft of the first steering engine and the front end of the first horn are connected and fixed, the One steering engine drives the first horn pivoting.First cabinet plays the role of protecting bottom steering engine and fixes the first steering engine.

Further, mechanical arm body realizes lifting in the vertical direction, also realizes displacement, the first machine in the longitudinal direction The control of the modality conversion horn steering engine of arm and the second horn, optimizes, based on the above technical solution by described The end of first horn and the second horn is respectively arranged with the second cabinet and third cabinet, and second steering engine is set to second In cabinet, the output shaft of the second steering engine is fixedly connected with the second horn and drives its pivoting；The third steering engine setting In in third cabinet, the output shaft of third steering engine is fixedly connected with execution fixture and it is driven to rotate coaxially.

Further, under normal circumstances, mechanical arm uses TPU material (Thermoplastic with flexible attribute Polyurethanes, thermoplastic polyurethane elastomer rubber) it is made, a degree of deformation can occurs in itself, control and disappear The kinematic accuracy of mechanical arm can be improved in the influence for subtracting deformation, therefore optimizes based on the above technical solution, described Second horn be it is rectangular, up, down, left and right four stress gauges are provided on the first horn, and be separately positioned on the first horn On four side surfaces, each pair of strain gauge is all made of Wheatstone half-bridge connection (direct current digital ratio electric bridge).Upper and lower two strains It is calculated as a pair, for detecting the deformation degree of the second horn in the vertical direction；Left and right two strains are calculated as a pair, for examining Survey the deformation degree of the second horn in the horizontal direction.

Further, can similarly carry out strain detecting design to the first horn, be provided on first horn it is left and Right two strain gauges, the strain gauge of left and right two are connected using Wheatstone half-bridge.Left and right two strain gauges on first horn For a pair, for detecting the deformation degree of the first horn in the horizontal direction.

Further, fixture is executed for realizing flexibility clamping, reduces the damage generated when executing, specific shape knot For structure according to following setting, the execution fixture includes pedestal, is provided on the pedestal through its front end face and rear end face Axis hole, the flexible gripping finger is set to the front end face of pedestal, and the performing steering wheel is set to the rear end face of pedestal, executes The output shaft of steering engine has been connected through a screw thread push head, and performing steering wheel drives push head reciprocating motion that flexible gripping finger is made to realize folding Clamping.

Further, in order to realize flexible clamping, a preferred technical solution can be used, the flexible gripping finger includes Outer layer flexible element and internal layer flexible element combine forming V-shape after the front end connection of two flexible elements, wherein the end of outer layer flexible element with Pedestal rotation connection, the end of internal layer flexible element and push head rotation connection, the reciprocating motion for pushing head drive clamp assemblies It opens and closes up.

Further, flexible gripping finger realizes that a kind of preferred connection type, pedestal described in gripping finger can be used in flexible deformation On be provided with connecting pin, be provided with outer layer connecting hole and outer layer connecting shaft on connecting pin, the outer layer flexible element be equipped with it is outer The corresponding connecting hole of layer connecting hole, the connecting hole that the outer layer connecting shaft passes through on outer layer connecting hole and outer layer flexible element make outer layer Flexible element is rotated relative to connecting pin；Internal layer connecting hole and internal layer connecting shaft are provided on the push head, the internal layer is flexible Part is equipped with connecting hole corresponding with internal layer connecting hole, and the internal layer connecting shaft passes through on internal layer connecting hole and internal layer flexible element Connecting hole makes internal layer flexible element relative to push head rotation.

Further, steering engine is the entirety of a closed loop, and only supporting PWM, (Pulse Width Modulation, pulse are wide Degree modulation) duty cycle signals realization position monocycle PID (ratio proportion, integral integral, differential Differential it) controls, does not support external extension programming.In order to realize the advanced feature of cooperation mechanical arm indispensability, to upper It states technical solution to improve, by the control chip gold of script in the control circuit of each steering engine, that tears open the utility model It removes, and integrates the chip of STM32 series on the control panel, chip is used to be changed according to the circuital current of each steering engine and control Its operation is made, is so achieved that freely controlling to steering engine.

Preferably, STM32F4 chip can be selected.

Above content discloses the structure composition of the cooperation mechanical arm, and the utility model also provides a kind of flexible cooperation The control method of mechanical arm, it is intended to judge whether mechanical arm collides by electric current induction, and after colliding to mechanical arm It is adjusted, is damaged caused by reduction in time；The dynamic deformation for judging mechanical arm according to strain gauge detection value simultaneously, to mechanical arm Deformation carry out static state and filter out, realize that the concussion of mechanical arm is eliminated, so that cooperation mechanical arm is more steady during the work time It is fixed reliable.

The control method of the cooperation mechanical arm disclosed by the utility model specifically comprises the following steps:

A kind of collision checking method of flexible mechanical arm, for controlling a kind of flexible mechanical arm described above, including such as Lower step:

S01: detection horn steering engine physical size and the mass center and rotary inertia for determining it use Denavit- Hartenberg parametric form is modeled, and the complete physical model of mechanical arm is obtained；

S02: IK Solvers equation is utilized, according to the output shaft angle of rotation of bottom steering engine, horn steering engine or performing steering wheel Degree calculates separately out theoretical torque value needed for corresponding steering engine maintains the rotational angle；

S03: according to relational expression T=I_estimated* Kt*i obtains I_estimated, wherein T is the theoretical torque in step S02 Value, Kt are constant of the machine, and i is the corresponding transmission ratio of each steering engine；

S04: in any time of mechanical arm operating, single order filtering is carried out to measured current, obtained current value is I_filtered；

S05: a threshold is preset, and according to relational expression | I_filtered-I_estimated| > threshold is sentenced It is disconnected, it is judged as the event of colliding if setting up, if invalid be judged as the event that do not collide；

S06: by each steering engine number consecutively since the steering engine of bottom, satisfaction collides event condition and the largest number of Steering engine inverts at once, realizes the rebound after collision with this, reduces and injure caused by collision.

In above-mentioned steps S03, theoretical torque value is acquired, is generally indicated by following analytic expression:

Torque_estimated=[(7766577*cos (conj (q2)) * sin (q2))/200000+ (1168371* sin(q3+conj(q2))*cos(conj(q3))*cos(q2))/312500+(8164863*sin(q3+conj(q2))*cos (conj(q3))*sin(conj(q4))*cos(q2)*cos(q4))/50000000+(18783207*sin(q3+conj (q2))*cos(conj(q3))*sin(conj(q4))*cos(q2)*sin(q4))/25000000+(737627187947634 0519521767333347834587637*sin(q3+conj(q2))*cos(conj(q3))*sin(conj(q4))*cos (q4)*sin(q2))/2028240960365167042394725128601600000000+(73762718794763405195 21767333347834587637*sin(q3+conj(q2))*sin(conj(q3))*sin(conj(q4))*cos(q2)*cos (q4))/2028240960365167042394725128601600000000+(86837139*sin(q3+conj(q2))*cos (conj(q3))^2*cos(conj(q4))*cos(q2)*sin(q4))/25000000,(1450899*cos(q2))/125000 +(256041*sin(q2))/250000,0,0]。

Further, it runs above-mentioned analytic expression and causes biggish computational burden, therefore advanced optimize, it is contemplated that mechanical arm The gravity that different postures are born is consecutive variations, and the variation of different angle is not that very acutely, the utility model uses will Sin and cos the two trigonometric function values, for unit discretization, and with 5 degree are in advance directly increasing with 5 degree by steering engine output shaft angle Meter calculates occurrence, and is stored in the control chip in the form of array constant.In this way, which the above torque expression formula just only relates to And simple addition subtraction multiplication and division is arrived, it can directly be realized in control panel with C language, can achieve the control frequency of 50Hz.

Further, if being in dragging teaching mode, once it detects and determines the above collision accident, it is only necessary to Obtain the size for the power that dragging teaching people provides according to the size of actual current value and theoretical current value difference value, and from difference Sign obtains external force direction.After obtaining external force direction and size, it is only necessary to be sent to corresponding joint steering engine equidirectional in proportion Movement instruction, dragging tutorial function can be realized.

It is the method detected in the ideal case to the collision of mechanical arm above, actual conditions are that mechanical arm is moving The vibration of middle generation vertically and horizontally, which leads to the dynamic deformation of mechanical arm, while mechanical arm is using flexible Material is made, and will cause static deformation；It carries out vibration and eliminates the precision that mechanical arm can be improved, needed in vibration is eliminated this is quiet State deformation is filtered out, and static deformation is often overlapped mutually with dynamic deformation, it is therefore desirable to the dynamic deformation of mechanical arm into Row variable filters out, and specifically comprises the following steps:

1) it is read using low frequency firstorder filter filtering strain gauge, is denoted as S_lowpass；

2) it is read using high frequency firstorder filter filtering strain gauge, is denoted as S_highpass；

3) the dynamic strain value S by filtering out is calculated according to the above results_filtered=S_highpass-S_lowpass；

4) ratio that strain gauge reading is introduced at steering engine loop feedback is controlled according to above-mentioned dynamic strain value, it may be assumed that V_i=V-V_s+S_filtered* p, wherein V_iFor speed ring input speed, V is target velocity, V_sFor present speed, p is constant.

Compared with prior art, the utility model has the following beneficial effects:

1. the utility model is light-weight, and has flexibility, collides to absorb and impact, reduce personal damage and machinery Arm damage.

2. the utility model reduces the labyrinth of tradition cooperation mechanical arm, the requirement to driving force is reduced, is used Driving can be realized in steering engine, reduces the cost of cooperation mechanical arm.

3. the utility model uses execution fixture flexible, it can be grabbed from multiple angles, the success rate of crawl is high.

4. the utility model measures mechanical arm deformation using strain gauge, and strain readings are introduced into position and speed control ring In, it realizes steering engine and actively offsets arm vibration, improve the control precision of mechanical arm.

5. being achieved at low cost collision detection and dragging teaching by way of carrying out current detecting to steering engine.

Detailed description of the invention

It, below will be to use required in embodiment in order to illustrate more clearly of the technical solution of the utility model embodiment Attached drawing be briefly described, it should be understood that the following drawings only shows the section Example of the utility model, therefore does not answer Regard the restriction to range as, for those of ordinary skill in the art, without creative efforts, may be used also To obtain other relevant attached drawings according to these attached drawings.

Fig. 1 is the overall structure diagram of the utility model.

Fig. 2 is the decomposition texture schematic diagram of the utility model.

Fig. 3 is the overall structure diagram for executing fixture.

Fig. 4 is the collision detection process schematic diagram of this cooperation mechanical arm.

Fig. 5 is the Principle of Process figure that this cooperation mechanical arm carries out shock absorbing.

In figure: 1- pedestal；The first cabinet of 2-；The first horn of 3-；The second cabinet of 4-；The second horn of 5-；6- third cabinet；7- Performing steering wheel；8- pedestal；9- flexibility gripping finger；901- outer layer flexible element；902- internal layer flexible element；The first steering engine of 10-；11- second Steering engine；12- third steering engine；13- pushes head；14- connecting pin.

Specific embodiment

With reference to the accompanying drawing and specific embodiment does further explaination to the utility model.

Embodiment 1:

As shown in Figure 1, Figure 2, Figure 3 shows, present embodiment discloses a kind of flexible cooperation mechanical arms, including pedestal 1, mechanical arm master The bottom end of body and execution fixture, the machinery arm body is connect with base rotation, executes the top that fixture is set to mechanical arm body. Specifically, being provided with control panel and bottom steering engine in the pedestal, bottom steering engine is for driving mechanical arm to horizontally rotate；Institute The mechanical arm body stated includes the first horn 3 and the second horn 5 of rotation connection, and the first horn and the second horn are by horn steering engine It is relatively rotated after driving in vertical direction；The execution fixture includes multiple flexible gripping fingers 9, executes fixture by performing steering wheel 7 Driving clamping；Bottom steering engine, horn steering engine and the performing steering wheel is electrically connected to control panel, and each steering engine and control panel Between be respectively connected with current sensor.

The present embodiment executes fixture by pedestal and mechanical arm body driving and realizes clamping operation, and pedestal realizes that mechanical arm exists The rotation of horizontal direction, the horn steering engine in mechanical arm body realize the movement on vertical direction, execute fixture and realize flexible clip It takes, avoids and damaged during clamping, while mechanical arm whole progress collision detection and concussion during the motion disappear Remove, avoid the expansion of injury, improve mechanical arm with people's collaborative and safety.

Preferably, in the present embodiment, the entire mechanical arm that cooperates is made by 3D printing technique.

First horn and the second horn drive mechanical arm by horn steering engine, in conjunction with the structure of mechanical arm body, The quantity of horn steering engine and position setting can influence the state of entire mechanical arm, optimize to above-mentioned technical proposal, described Horn steering engine include the first steering engine 10, the second steering engine 11 and third steering engine 12, first steering engine is set to the first horn At front end, second steering engine and third steering engine are respectively arranged at the front end and end of the second horn.This prioritization scheme will pass The six degree of freedom structure of system cooperation mechanical arm is simplified, and is reduced the overall volume of mechanical arm, is reduced mechanical arm itself Weight alleviates the burden of steering engine, makes the reduction of mechanical arm service requirement, and practicability is stronger.

In the present embodiment, the mechanical arm body and pedestal relative level are rotated, and mechanical arm body is real by its front end Now with the rotation connection of pedestal, guarantee other freedom degrees of mechanical arm body it is unaffected in the case where, to above-mentioned technical proposal It optimizes, the front end of first horn is provided with the first cabinet 2, and the output axis connection of the first cabinet and bottom steering engine is simultaneously It rotates coaxially；First steering engine is located in the first cabinet, and the output shaft of the first steering engine and the front end of the first horn are connected and fixed, First steering engine drives the first horn pivoting.First cabinet plays the role of protecting bottom steering engine and fixes the first steering engine.

Mechanical arm body realizes lifting in the vertical direction, also realizes displacement, the first horn and second in the longitudinal direction The modality conversion horn steering engine of horn controls, and optimizes based on the above technical solution, passes through first horn It is respectively arranged with the second cabinet 4 and third cabinet 6 with the end of the second horn, second steering engine is set to the second cabinet Interior, the output shaft of the second steering engine is fixedly connected with the second horn and drives its pivoting；The third steering engine is set to In three cabinets, the output shaft of third steering engine is fixedly connected with execution fixture and it is driven to rotate coaxially.

In the present embodiment, mechanical arm uses TPU material (Thermoplastic with flexible attribute Polyurethanes, thermoplastic polyurethane elastomer rubber) it is made, a degree of deformation can occurs in itself, control and disappear The kinematic accuracy of mechanical arm can be improved in the influence for subtracting deformation, therefore optimizes based on the above technical solution, described Second horn be it is rectangular, up, down, left and right four stress gauges are provided on the first horn, and be separately positioned on the first horn On four side surfaces, each pair of strain gauge is all made of

The connection of Wheatstone half-bridge.Upper and lower two strains are calculated as a pair, for detecting the second horn in the vertical direction Deformation degree；Left and right two strains are calculated as a pair, for detecting the deformation degree of the second horn in the horizontal direction.

Strain detecting design can be similarly carried out to the first horn, and the strain of left and right two is provided on first horn Meter, the strain gauge of left and right two are connected using Wheatstone half-bridge.Left and right two strains are calculated as a pair on first horn, use In the deformation degree of the first horn of detection in the horizontal direction.

Fixture is executed for realizing flexibility clamping, reduces the damage generated when executing, specific shape and structure is according to such as Lower setting, the execution fixture include pedestal 8, and the axis hole through its front end face and rear end face is provided on the pedestal, The flexible gripping finger is set to the front end face of pedestal, and the performing steering wheel is set to the rear end face of pedestal, performing steering wheel Output shaft has been connected through a screw thread push head 13, and performing steering wheel drives push head reciprocating motion that flexible gripping finger is made to realize flange splint It takes.

In order to realize flexible clamping, a preferred technical solution can be used, the flexible gripping finger includes outer layer flexibility Part and internal layer flexible element combine forming V-shape after the front end connection of two flexible elements, wherein the end of outer layer flexible element 901 and pedestal Rotation connection, the end of internal layer flexible element 902 and push head rotation connection, the reciprocating motion for pushing head drive clamp assemblies to open With close up.

Flexible gripping finger realizes that a kind of preferred connection type, the company of being provided on pedestal described in gripping finger can be used in flexible deformation Pin is provided with outer layer connecting hole and outer layer connecting shaft on connecting pin, and the outer layer flexible element is equipped with and outer layer connecting hole pair The connecting hole answered, the connecting hole that the outer layer connecting shaft passes through on outer layer connecting hole and outer layer flexible element keep outer layer flexible element opposite Connecting pin rotation；Be provided with internal layer connecting hole and internal layer connecting shaft on the push head, the internal layer flexible element be equipped with The corresponding connecting hole of internal layer connecting hole, the connecting hole that the internal layer connecting shaft passes through on internal layer connecting hole and internal layer flexible element make interior Layer flexible element is relative to push head rotation.

Steering engine is the entirety of a closed loop, only PWM duty cycle signal is supported to realize position monocycle PID control, not supported Outside extension programming.In order to realize the advanced feature of cooperation mechanical arm indispensability, above-mentioned technical proposal is improved, this is practical new Type integrates that dismounting of the control chip gold of script in the control circuit of each steering engine on the control panel The chip of STM32 series, chip are used to so be achieved that according to its operation of the circuital current of each steering engine variation control to rudder Machine freely controls.

In the present embodiment, STM32F4 chip can be selected.

Embodiment 2:

As shown in Figure 4, Figure 5, embodiment 1 discloses the structure composition of the cooperation mechanical arm, and the present embodiment provides one The control method of the flexible cooperation mechanical arm of kind, it is intended to judge whether mechanical arm collides by electric current induction, and to mechanical arm It is adjusted after colliding, is damaged caused by reduction in time；The dynamic shape of mechanical arm is judged according to strain gauge detection value simultaneously Become, static state is carried out to the deformation of mechanical arm and is filtered out, realize that the concussion of mechanical arm is eliminated, so that cooperation mechanical arm is worked It is more reliable and more stable in journey.

The control method of the cooperation mechanical arm disclosed in the present embodiment specifically comprises the following steps:

A kind of collision checking method of flexible mechanical arm, for controlling a kind of flexible mechanical arm described in embodiment 1, including Following steps:

Torque_estimated=[(7766577*cos (conj (q2)) * sin (q2))/200000+ (1168371* sin(q3+conj(q2))*cos(conj(q3))*cos(q2))/312500+(8164863*sin(q3+conj(q2))*cos (conj(q3))*sin(conj(q4))*cos(q2)*cos(q4))/50000000+(18783207*sin(q3+conj (q2))*cos(conj(q3))*sin(conj(q4))*cos(q2)*sin(q4))/25000000+(737627187947634 0519521767333347834587637*sin(q3+conj(q2))*cos(conj(q3))*sin(conj(q4))*cos (q4)*sin(q2))/2028240960365167042394725128601600000000+(73762718794763405195 21767333347834587637*sin(q3+conj(q2))*sin(conj(q3))*sin(conj(q4))*cos(q2)*cos (q4))/2028240960365167042394725128601600000000+(86837139*sin(q3+conj(q2))*cos (conj(q3))^2*cos(conj(q4))*cos(q2)*sin(q4))/25000000,(1450899*cos(q2))/125000 +(256041*sin(q2))/250000,0,0].Wherein q1, q2, q3, q4 are respectively bottom steering engine, the first steering engine, the second rudder The output shaft rotational angle of machine, third steering engine.

It runs above-mentioned analytic expression and causes biggish computational burden, therefore advanced optimize, it is contemplated that mechanical arm difference posture The gravity of receiving is consecutive variations, and the variation of different angle is not that very acutely, the utility model uses and exports steering engine Shaft angle degree is with 5 degree for unit discretization, and the two trigonometric function values are directly gone out in advance with 5 degree for incremental computations by sin and cos Occurrence, and stored in the control chip in the form of array constant.In this way, which the above torque expression formula just relates only to simply Addition subtraction multiplication and division, can directly be realized in control panel with C language, can achieve the control frequency of 50Hz.

If being in dragging teaching mode, once it detects and determines the above collision accident, it is only necessary to according to reality The size of current value and theoretical current value difference value obtains the size for the power that dragging teaching people provides, and obtains from the sign of difference To external force direction.After obtaining external force direction and size, it is only necessary to send equidirectional movement in proportion to corresponding joint steering engine and refer to It enables, dragging tutorial function can be realized.

Above is the several embodiments that the utility model is enumerated, but the utility model is not limited to above-mentioned optional reality Apply mode, those skilled in the art can obtain other numerous embodiments according to the mutual any combination of aforesaid way, anyone Other various forms of embodiments can be all obtained under the enlightenment of the utility model.Above-mentioned specific embodiment should not be understood in pairs The limitation of the protection scope of the utility model, the protection scope of the utility model should be subject to be defined in claims, And specification can be used for interpreting the claims.

Claims

1. a kind of flexible cooperation mechanical arm, including pedestal (1), mechanical arm body and execution fixture, the bottom of the machinery arm body End is connect with base rotation, executes the top that fixture is set to mechanical arm body；It is characterized by: being provided with control in the pedestal Making sheet and bottom steering engine, bottom steering engine is for driving mechanical arm to horizontally rotate；The mechanical arm body includes rotation connection First horn (3) and the second horn (5), the first horn and the second horn by turning after horn servo driving in vertical direction relatively It is dynamic；The execution fixture includes multiple flexible gripping fingers (9), executes fixture by performing steering wheel (7) and drives clamping；The bottom Steering engine, horn steering engine and performing steering wheel are electrically connected to control panel, and electric current biography is respectively connected between each steering engine and control panel Sensor.

2. flexible cooperation mechanical arm according to claim 1, it is characterised in that: the horn steering engine includes the first steering engine (10), the second steering engine (11) and third steering engine (12), first steering engine are set at the front end of the first horn, second rudder Machine and third steering engine are respectively arranged at the front end and end of the second horn.

3. flexible cooperation mechanical arm according to claim 2, it is characterised in that: the front end of first horn is provided with First cabinet (2), the output axis connection of the first cabinet and bottom steering engine simultaneously rotate coaxially；First steering engine is located at the first cabinet Interior, the output shaft of the first steering engine and the front end of the first horn are connected and fixed, and the first steering engine drives the first horn pivoting.

4. flexible cooperation mechanical arm according to claim 2, it is characterised in that: first horn and the second horn End is respectively arranged with the second cabinet (4) and third cabinet (6), and second steering engine is set in the second cabinet, the second rudder The output shaft of machine is fixedly connected with the second horn and drives its pivoting；The third steering engine is set in third cabinet, The output shaft of third steering engine is fixedly connected with execution fixture and it is driven to rotate coaxially.

5. flexible cooperation mechanical arm according to claim 2, it is characterised in that: second horn be it is rectangular, first It is provided with up, down, left and right four stress gauges on horn, and is separately positioned on four side surfaces of the first horn, every a pair Strain gauge is all made of the connection of direct current digital ratio electric bridge.

6. flexible cooperation mechanical arm according to claim 2, it is characterised in that: be provided on first horn it is left and Right two strain gauges, the strain gauge of left and right two are connected using direct current digital ratio electric bridge.

7. flexible cooperation mechanical arm according to claim 1, it is characterised in that: the execution fixture includes pedestal (8), The axis hole through its front end face and rear end face is provided on the pedestal, the flexible gripping finger is set to the front end of pedestal Face, the performing steering wheel are set to the rear end face of pedestal, and the output shaft of performing steering wheel has been connected through a screw thread push head (13), Performing steering wheel drives push head reciprocating motion that flexible gripping finger is made to realize folding clamping.

8. flexible cooperation mechanical arm according to claim 7, it is characterised in that: the flexible gripping finger includes outer layer flexibility Part and internal layer flexible element combine forming V-shape after the front end connection of two flexible elements, wherein the end of outer layer flexible element (901) and seat Body rotation connection, the end of internal layer flexible element (902) and push head rotation connection, the reciprocating motion for pushing head drive clamp assemblies It opens and closes up.

9. flexible cooperation mechanical arm according to claim 8, it is characterised in that: be provided with connecting pin on the pedestal (14), outer layer connecting hole and outer layer connecting shaft are provided on connecting pin, the outer layer flexible element is equipped with and outer layer connecting hole pair The connecting hole answered, the connecting hole that the outer layer connecting shaft passes through on outer layer connecting hole and outer layer flexible element keep outer layer flexible element opposite Connecting pin rotation；Be provided with internal layer connecting hole and internal layer connecting shaft on the push head, the internal layer flexible element be equipped with The corresponding connecting hole of internal layer connecting hole, the connecting hole that the internal layer connecting shaft passes through on internal layer connecting hole and internal layer flexible element make interior Layer flexible element is relative to push head rotation.

10. flexible cooperation mechanical arm according to claim 1, it is characterised in that: integrate STM32 system on the control panel The chip of column, chip are used to control the operation of each steering engine.