CN113043270A - Automatic high-precision resetting method of rope-driven flexible mechanical arm based on tooling condition - Google Patents

Automatic high-precision resetting method of rope-driven flexible mechanical arm based on tooling condition Download PDF

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CN113043270A
CN113043270A CN202110200495.2A CN202110200495A CN113043270A CN 113043270 A CN113043270 A CN 113043270A CN 202110200495 A CN202110200495 A CN 202110200495A CN 113043270 A CN113043270 A CN 113043270A
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rope
motor
driving
current
mechanical arm
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CN113043270B (en
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徐文福
黄曦
黄一帆
袁晗
梁斌
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Shenzhen Graduate School Harbin Institute of Technology
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Shenzhen Graduate School Harbin Institute of Technology
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00—Programme-controlled manipulators
    • B25J9/16—Programme controls
    • B25J9/1628—Programme controls characterised by the control loop
    • B25J9/1635—Programme controls characterised by the control loop flexible-arm control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00—Programme-controlled manipulators
    • B25J9/10—Programme-controlled manipulators characterised by positioning means for manipulator elements
    • B25J9/104—Programme-controlled manipulators characterised by positioning means for manipulator elements with cables, chains or ribbons
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

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  • Robotics (AREA)
  • Mechanical Engineering (AREA)
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Abstract

The invention relates to an automatic high-precision resetting method of a rope-driven flexible mechanical arm based on a tooling condition, which comprises the following steps of: establishing a transmission relationship between an armature current of the motor and a tension of the rope; determining a rope pre-tightening force range and calculating a corresponding driving current threshold value based on the limit tension of the driving rope; triggering the driving box to loosen the driving rope, so that the arm lever assembly of the rope-driven flexible mechanical arm is limited by the clamp; controlling the driving current of the motor to rise, and stabilizing the driving current at a driving current threshold value at an exponential speed according to armature current feedback sensed in real time. The automatic high-precision resetting method for the rope-driven flexible mechanical arm provided by the invention avoids low-efficiency and tedious manual pre-tightening operation, and realizes quick automatic high-precision resetting of the rope-driven flexible mechanical arm.

Description

Automatic high-precision resetting method of rope-driven flexible mechanical arm based on tooling condition
Technical Field
The invention belongs to the technical field of flexible mechanical arm control, and particularly relates to an automatic high-precision resetting method and device of a rope-driven flexible mechanical arm based on a tooling condition.
Background
At present, the rope-driven flexible mechanical arm has the characteristics of light weight, flexibility, strong adaptability to complex environments, strong anti-interference capability and the like, so that the rope-driven flexible mechanical arm has great advantages in the fields of aviation, aerospace, nuclear power and the like. Before the rope-driven flexible mechanical arm is normally used, the rope-driven flexible mechanical arm needs to be reset to an initial state, wherein the resetting precision has a remarkable influence on the working precision of the rope-driven flexible mechanical arm. At present, the resetting of the rope-driven flexible mechanical arm is mainly completed manually, the operation is low in efficiency, and the resetting precision is difficult to guarantee.
Disclosure of Invention
The invention provides an automatic high-precision resetting method and device of a rope-driven flexible mechanical arm based on a tooling condition, and aims to at least solve one of the technical problems in the prior art. For example, the rope-driven flexible mechanical arm of the existing driving system is used for automatic high-precision quick reset, so that the problems of low efficiency and low precision of manual reset are solved.
The rope-driven flexible mechanical arm applied to the invention comprises a driving box and a plurality of sections of arm rod assemblies which are connected in series, wherein each arm rod assembly comprises a central block and an arm rod which are connected in an articulated mode, the arm rod in each arm rod assembly is connected to the driving box through a respective driving rope, and the driving box comprises a plurality of motors and a plurality of transmission mechanisms. Every drive mechanism include the shaft coupling, with the shaft coupling connect the lead screw, with lead screw complex ball nut, by the slider and the guide rail of ball nut drive the slider carries out linear movement, wherein motor and shaft coupling connect, the slider links firmly with the rope for by ball nut drive slider and then drive the rope motion when the motor rotates.
The technical scheme of the invention relates to an automatic high-precision resetting method of a rope-driven flexible mechanical arm based on a tooling condition, wherein a plurality of sections of arm rod assemblies are limited at a resetting initial position through a clamp under the tooling condition, so that the method comprises the following steps:
s10, establishing a transmission relation between the armature current of the motor and the tension of the rope;
s20, determining a rope pretightening force range and calculating a corresponding driving current threshold value based on the limit tension of the driving rope;
s30, triggering the driving box to loosen the driving rope, and enabling the rope to drive an arm lever assembly of the flexible mechanical arm to be limited by the clamp;
and S40, controlling the drive current of the motor to rise, and stabilizing the drive current at a drive current threshold value at an exponential speed according to the armature current feedback sensed in real time.
Further, said step S10 includes establishing a relationship between rope tension and motor armature current by the following formula to process or monitor rope tension during motor current control:
Figure BDA0002948005280000021
wherein, FcableFor rope tension, S is lead of lead screw, eta is transmission efficiency, alpha is dimensionless constant, KtIs the torque constant of the motor, iaIs the armature current.
Further, the step S20 includes:
s21, treating the coulomb friction force on the rope as a constant value, and limiting the rope pretightening force Fpre≤εFmaxWherein epsilon is a safety factor for ensuring that the rope-driven flexible mechanical arm has enough tension variation range, the range is between 0.01 and 0.15, FmaxThe allowable limit tension of the rope;
s22, calculating the drive current threshold value of the armature of the motor as
Figure BDA0002948005280000022
Further, the step S30 includes:
and the brake of the motors is released through the controller of the mechanical arm, so that the arm rod assemblies are allowed to keep a linear serial horizontal state after being limited by the clamp.
Further, the step S40 includes:
s41, configuring according to the sequence, triggering and controlling the armature current of each motor, and starting to reset the mechanical arm;
s42, periodically acquiring a feedback signal of the armature current of the driving motor through a Hall element;
and S43, when the driving current rises and approaches to the driving current threshold, based on a current loop control law, performing proportional-integral feedback control on the driving current to enable the driving current to be stabilized at the driving current threshold so as to realize the reset of the mechanical arm.
Further, the step S41 further includes:
every three ropes are arranged in the mechanical arm to control the rotation angle of the joint of one section of arm rod assembly;
and each driving rope is sequentially pre-tightened and reset in a segmented mode according to the sequence from the driving box base to the tail end of the mechanical arm.
Further, the motor is a dc motor, and step S43 further includes:
when the average value of the driving current acquired continuously for multiple times reaches a driving current threshold value of 0.2 times, judging that the driving current is close to the threshold value sufficiently;
and introducing the following current loop control equation to perform proportional integral feedback control on the driving current:
Figure BDA0002948005280000023
wherein u isaIs the armature voltage of the DC motor, KiIs a constant much greater than 1, TaIs the electromagnetic time constant of the motor, euFor motor input voltage uiAnd a feedback voltage uaThe difference between the difference of the two phases,
eu＝ui-ua＝ui-iaγ；
wherein u isiFor input voltage, iaFeedback system for armature current, gamma for Hall elementAnd (4) counting.
Further, the step S43 further includes:
when the drive current is detected to be close to the drive current threshold value, the input voltage u of the motor is controlled according to the following formulaiSo that the armature current iaStabilizes around the threshold value at an exponential rate for a finite time of multiple time constants:
Figure BDA0002948005280000031
wherein T is a control period, τuIs a time constant, uthr＝ithrRaIs equal to the current threshold ithrCorresponding voltage threshold value, wherein RaIs the internal resistance of the motor.
The invention also relates to a computer-readable storage medium, on which computer program instructions are stored, which, when executed by a processor, implement the above-mentioned method.
The technical scheme of the invention also relates to an automatic high-precision resetting device of the rope-driven flexible mechanical arm based on the tooling condition, which comprises the following components: the computer-readable storage medium; make the arm pole subassembly of multistage spacing anchor clamps at initial position that resets under the frock condition, anchor clamps include a plurality of location support group framves that are used for cup jointing the periphery of arm pole and establish ties the linear type cylinder stick of a plurality of location support group framves.
The beneficial effects of the invention are as follows.
The invention innovatively provides an automatic high-precision resetting method of a rope-driven flexible mechanical arm based on drive current control under a tooling condition, which comprises the steps of establishing a transmission relation between armature current of a drive motor and rope tension, setting rope pretightening force and calculating corresponding drive current threshold, installing a clamp to limit the rope-driven flexible mechanical arm, and sensing and controlling the armature current of the drive motor in real time to enable the armature current to be stabilized at the drive current threshold at exponential speed. The scheme of the invention realizes automatic high-precision quick reset of the rope-driven flexible mechanical arm by using the existing driving system, and solves the problems of low efficiency and low precision of manual reset.
Drawings
Fig. 1 is a general flow diagram of a method according to the invention.
Fig. 2 is a schematic view of a fixture tooling condition of a rope driven flexible robot arm according to an embodiment of the present invention.
Fig. 3 is a schematic view of a drive box portion module of a rope driven flexible robot arm in accordance with an embodiment of the present invention.
Fig. 4 is a model block diagram of a torque balance equation and a voltage balance equation of a dc motor according to an embodiment of the present invention.
Fig. 5 is a simplified motor model control block diagram incorporating a current loop in an embodiment in accordance with the invention.
Fig. 6 is a graph of an armature current settling at an exponential rate around a threshold value for a finite time in an embodiment in accordance with the invention.
Detailed Description
The conception, the specific structure and the technical effects of the present invention will be clearly and completely described in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the schemes and the effects of the present invention.
As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any combination of one or more of the associated listed items.
In some embodiments of the invention, referring to fig. 2 and 3, a rope-driven flexible robot arm 1 to which the method and apparatus according to the invention are applied comprises a drive housing and a series of multi-segment arm bar assemblies, each arm bar assembly comprising an articulated center block and an arm bar, the arm bars in each arm bar assembly being connected to the drive housing by respective drive ropes. The drive box includes a plurality of motors 111 and a plurality of transmission mechanisms. Each transmission mechanism comprises a coupler 112, a screw 113 connected with the coupler 112, a ball nut 114 matched with the screw 113, a slider 115 driven by the ball nut 114, and a guide rail 116 guiding the slider 115 to move linearly, wherein the motor 111 is connected with the coupler 112, and the slider 115 is fixedly connected with a rope 117, so that the ball nut 114 drives the slider 115 to further drive the rope to move when the motor 111 rotates. The remaining details regarding the rope-driven flexible robot arm can be found in the applicant's prior publication CN111993400A entitled "flexible robot arm with end force feedback". This publication is incorporated herein by reference in its entirety for the sake of economy.
Referring to fig. 1, in some embodiments, a method according to the present invention includes the steps of:
s10, establishing a transmission relation between the armature current of the motor and the tension of the rope;
s20, determining a rope pretightening force range and calculating a corresponding driving current threshold value based on the limit tension of the driving rope;
s30, triggering the driving box to loosen the driving rope, and enabling the rope to drive an arm lever assembly of the flexible mechanical arm to be limited by the clamp;
and S40, controlling the drive current of the motor to rise, and stabilizing the drive current at a drive current threshold value at an exponential speed according to the armature current feedback sensed in real time.
In an embodiment, step S10 may further include: an output torque corresponding to the armature current of the driving motor is calculated from the torque constant of the motor of the driving module, and the tension of the driving rope corresponding to the motor is calculated from the force transmission relationship of the driving module (shown in fig. 3) composed of the motor 111, the coupling 112, the lead screw 113, the nut 114, the slider 115, the guide rail 116, and the rope 117. The force transmission relationship of the driving module relates to the structural parameters and the transmission efficiency of the driving module.
The drive motor outputs a torque TmAnd armature current iaIs calculated according to the following equation:
Tm＝Ktia；
wherein, KtIs the torque constant of the drive motor.
Said drive rope tension FcableAnd the output torque T of the driving motormThe force transmission relationship therebetween is calculated as follows:
Figure BDA0002948005280000041
wherein S is the lead of the screw rod, eta is the transmission efficiency of a transmission system consisting of the screw rod, the slide block, the guide rail and the rope, and preferably alpha is a dimensionless constant less than 0.1.
Tensioning the drive rope FcableAnd the output torque T of the driving motormSubstituting the force transmission relationship between the two into the output torque T of the driving motormAnd armature current iaThe relationship of (a) is calculated as:
Figure BDA0002948005280000051
preferably, the rope tension can be directly and dynamically controlled through the motor current, the response is flexible, and the current protection function is provided. For example, by the above-mentioned drive rope tension calculation formula, the armature current is collected during the control of the motor current to indirectly calculate the rope tension to monitor the rope tension to avoid exceeding the limit tension of the rope. For example, the motor current is inversely calculated according to the current tension of the rope by the drive rope tension calculation formula, so that the current is prevented from being overlarge during the control of the motor.
After establishing the transmission relationship between the armature current of the driving motor and the rope tension, the setting of the rope pretightening force and the calculation of the corresponding driving current threshold value are required.
As shown in fig. 3, according to the structural characteristics of the joint grouping configuration of the rope-driven flexible mechanical arm, the pre-tightening force required by the restoration of the driving ropes corresponding to the different joints can be calculated according to the friction force between the ropes and the rope holes and the ultimate tension of the ropes.
The method comprises the following steps of calculating a threshold value of the armature current based on a rope pretightening force relation. The restoring pretension of the drive rope needs to overcome the friction force F between the rope and the rope holefAnd can maintain a certain rigidity k of the flexible mechanical armθThe self gravity and the external interference force of the flexible mechanical arm are overcome. The pre-tightening force of the drive rope is simultaneously subjected to the ultimate tension FmaxDue to the limitation of the control system, the variation range of the tensile force of the rope in the working process can be reduced due to overlarge pretightening force, so that the working range of the rope-driven flexible mechanical arm is limited. Preferably, the pretension force F of the drive ropepreSatisfies the following formula:
Fpre＝Ff+βkθ≤εFmax；
friction force F between the rope and the rope holefMainly comprises coulomb friction force, and when the rope drives the flexible mechanical arm to be limited by the clamp, each joint angle is almost positioned at a zero position. So that the frictional force F is present herefIndependent of joint angle and under rope tension FcableThe influence is not significant and is therefore taken as a constant value, i.e. the measured mean value.
Wherein β is a constant with a dimension rad/m. Epsilon is a safety factor for ensuring that the rope-driven flexible mechanical arm has a sufficient tension variation range, and preferably epsilon is a dimensionless constant between 0.01 and 0.15.
Thus, in one embodiment, in step S20, the setting of the rope pretension and the calculation of the corresponding drive current threshold include: calculating the threshold value of the armature current of the driving motor through the mechanical transmission relation of the driving module and the pretightening force of the driving rope corresponding to the driving motor
Figure BDA0002948005280000052
In one embodiment, in step S30, according to the structural characteristics of the rope-driven flexible mechanical arm, the driving rope 117 of the rope-driven flexible mechanical arm 1 is first appropriately loosened and then mounted to the clamp 2 consisting of the cylindrical rod 22 and the plurality of positioning support brackets 21 for limiting, so that the accuracy of the reset initial position of the flexible mechanical arm can be ensured by the processing and positioning accuracy of the clamp, as shown in fig. 2 and 3.
With continued reference to FIG. 2, the alignment support nest 21 includes a hollow cylindrical portion having an inside diameter substantially the same as or matching the diameter of the cylindrical outer periphery of the arm and a foot portion. The hollow cylinder part of each positioning support group frame 21 is sleeved with the cylindrical periphery of two adjacent arm rods, so that the two adjacent sleeved arm rods keep straight line coaxiality under the mechanical size constraint of the inner diameter of the hollow cylinder part. Further, the cylindrical rod 22 may be a linear rigid rod connecting a plurality of position support brackets in series so that the hollow cylindrical portions of the plurality of position support brackets 21 are kept linearly coaxial. Therefore, the brake of a plurality of motors can be released through the controller of the mechanical arm or the motors can drive the transmission mechanism to loosen the ropes so as to allow a plurality of arm rod assemblies to be easily limited by the clamp and then keep a linear serial horizontal state (the horizontal state preferably refers to a horizontal state after the driving box and the arm rod assemblies in multiple sections of serial connection are coaxial, as shown in fig. 2).
In one embodiment, in step S40, the armature currents of the driving motors are controlled in a certain sequence to reset the rope-driven flexible mechanical arm. By periodically collecting feedback signals of the armature current of the driving motor, when the driving current continuously rises to reach the calculated threshold, an optimal current loop control law is set, and Proportional Integral (PI) feedback control is carried out on the driving current, so that the driving current is stabilized at the set threshold, and automatic high-precision resetting of the rope-driven flexible mechanical arm is realized.
Every three ropes of the rope-driven flexible mechanical arm control the rotation angle of a group of joints, and preferably, the driving ropes are grouped in sequence from the base to the tail end to be pre-tightened and reset. The driving current of each rope is periodically fed back to the control system in real time through the Hall element, and whether the driving current is close to the threshold value is judged according to the following formula:
Figure BDA0002948005280000064
that is, when the average value of the drive current acquired k times reaches 0.2 times of the drive current threshold, it is determined that the drive current is sufficiently close to the threshold. Preferably, k is an integer greater than 10 and less than 100 for the drive current acquisition period.
The direct current motor satisfies a voltage balance equation and a torque balance equation as shown in the following formulas:
Figure BDA0002948005280000061
Figure BDA0002948005280000062
wherein J is the rotational inertia of the motor, RaIs the internal resistance of the motor, L is the inductance of the motor, KeIs the back electromotive force constant of the motor, theta is the motor rotation angle, TdFor loading a moment of the motor, KtIs the torque constant of the motor.
As shown in fig. 4, the voltage balance equation and the torque balance equation of the dc motor are subjected to pull-type transformation and can be represented in a block diagram form. In the figure, Ω(s) is the motor speed.
In order to directly control the armature current of the driving motor, a current loop is required to be introduced to simplify the direct current motor model.
After the driving current approaches to a threshold value, introducing a current loop shown by the following formula, and performing PI feedback control on the driving current:
Figure BDA0002948005280000063
wherein u isaIs the armature voltage of the DC motor, KiIs a constant much greater than 1, TaIs the electromagnetic time constant of the motor.Under this condition, the motor input voltage uiAnd armature current iaApproximately satisfying the proportional relationship. e.g. of the typeuFor motor input voltage uiAnd the difference between the feedback voltage, as shown in the following equation:
eu＝ui-ua＝ui-iaγ；
gamma is the feedback coefficient of the hall element. Further, when gamma is taken as the internal resistance R of the motoraWhile, the motor input voltage uiAnd armature current iaOhm's law is approximately satisfied as follows:
ui≈ia Ra；
with the above simplification, the input voltage u can be approximated by controlling the motoriDirect control of armature current iaAnd further controlling the output torque T of the motormAnd rope tension Fcable。
FIG. 5 shows a control block diagram of a motor model with a simplified current loop, in which a simplified electromagnetic time constant T'aAnd the value is approximately equal to 0, and the omega(s) is the rotating speed of the motor.
Setting the time constant τuWhen the drive current is detected to be close to the threshold value, the input voltage u of the motor is controlled according to the following formulaiSo that the armature current iaStabilize around the threshold value at an exponential rate for a finite time of about 3 time constants:
Figure BDA0002948005280000071
wherein u isthr＝ithrRaIs a voltage threshold corresponding to the current threshold, and T is a control period. Preferably, the time constant τuSet between 0.2s and 0.5 s.
FIG. 6 is a graph of the response of the armature current, i, to the armature current in a simulation calculation of the method of the present inventionaStabilize around the threshold value at an exponential rate for a finite time. For example, after a first control period (e.g., 50ms), when the rising armature current reaches a drive current threshold of 0.2 timesIt is determined to be close enough to the threshold value to employ PI feedback control in a second control period (e.g., 50ms to 100ms) such that the armature current iaRapidly up to 1 time the drive current threshold. As can be understood from this simulation example, at the time of the first control cycle, the control current of each motor is linearly increased, and the rope is slowly tightened by each motor corresponding to the robot arm. Because the rope-driven flexible mechanical arm is limited at the reset target mechanical position by the clamp, when the driving current of the motor needs to be increased continuously, the current needs to be increased rapidly in the second control period, so that the armature current needs to be increased exponentially; at the moment, all motors corresponding to the mechanical arm quickly tighten the ropes, and all arm rod assemblies can be simultaneously tightened and stably pre-tightened (because the armature current is stable) to the greatest extent, so that the high-precision resetting of all the arm rod assemblies of the mechanical arm is achieved.
It should be recognized that the method steps in embodiments of the present invention may be embodied or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer readable memory. The method may use standard programming techniques. Each program may be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) can be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language. Furthermore, the program can be run on a programmed application specific integrated circuit for this purpose.
Further, the operations of processes described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The processes described herein (or variations and/or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as code (e.g., executable instructions, one or more computer programs, or one or more applications) collectively executed on one or more processors, by hardware, or combinations thereof. The computer program includes a plurality of instructions executable by one or more processors.
Further, the method may be implemented in any type of computing platform operatively connected to a suitable interface, including but not limited to a personal computer, mini computer, mainframe, workstation, networked or distributed computing environment, separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, and the like. Aspects of the invention may be embodied in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optically read and/or write storage medium, RAM, ROM, or the like, such that it may be read by a programmable computer, which when read by the storage medium or device, is operative to configure and operate the computer to perform the procedures described herein. Further, the machine-readable code, or portions thereof, may be transmitted over a wired or wireless network. The invention described herein includes these and other different types of non-transitory computer-readable storage media when such media include instructions or programs that implement the steps described above in conjunction with a microprocessor or other data processor. The invention may also include the computer itself when programmed according to the methods and techniques described herein.
A computer program can be applied to input data to perform the functions described herein to transform the input data to generate output data that is stored to non-volatile memory. The output information may also be applied to one or more output devices, such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including particular visual depictions of physical and tangible objects produced on a display.
The above description is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiment, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention as long as the technical effects of the present invention are achieved by the same means. The invention is capable of other modifications and variations in its technical solution and/or its implementation, within the scope of protection of the invention.

Claims (10)

1. An automatic high-precision resetting method of a rope-driven flexible mechanical arm based on a tooling condition, wherein the mechanical arm comprises a driving box and a plurality of sections of arm rod assemblies which are connected in series, each arm rod assembly comprises a central block and an arm rod which are connected in an articulated manner, the arm rod in each arm rod assembly is connected to the driving box through a respective driving rope, the driving box comprises a plurality of motors and a plurality of transmission mechanisms, the automatic high-precision resetting method is characterized in that the plurality of sections of arm rod assemblies are limited at a resetting initial position through a clamp under the tooling condition, and the method comprises the following steps:
s10, establishing a transmission relation between the armature current of the motor and the tension of the rope;
s20, determining a rope pretightening force range and calculating a corresponding driving current threshold value based on the limit tension of the driving rope;
s30, triggering the driving box to loosen the driving rope, and enabling the rope to drive an arm lever assembly of the flexible mechanical arm to be limited by the clamp;
and S40, controlling the drive current of the motor to rise, and stabilizing the drive current at a drive current threshold value at an exponential speed according to the armature current feedback sensed in real time.
2. The method of claim 1, wherein each of the transmission mechanisms comprises a shaft coupler, a lead screw connected to the shaft coupler, a ball nut engaged with the lead screw, a slider driven by the ball nut, and a guide rail for guiding the slider to move linearly, wherein the motor is connected to the shaft coupler, the slider is fixedly connected to the rope, such that the slider is driven by the ball nut to move the rope when the motor rotates, and wherein the step S10 comprises establishing a relationship between rope tension and armature current of the motor by the following formula to process or monitor the rope tension during the motor current control:
Figure FDA0002948005270000011
wherein, FcableFor rope tension, S is lead of lead screwEta is transmission efficiency, alpha is a dimensionless constant, KtIs the torque constant of the motor, iaIs the armature current.
3. The method according to claim 2, wherein the step S20 includes:
s21, treating the coulomb friction force on the rope as a constant value, and limiting the rope pretightening force Fpre≤εFmaxWherein epsilon is a safety factor for ensuring that the rope-driven flexible mechanical arm has enough tension variation range, the range is between 0.01 and 0.15, FmaxThe allowable limit tension of the rope;
s22, calculating the drive current threshold value of the armature of the motor as
Figure FDA0002948005270000012
4. The method according to claim 1, wherein the step S30 includes:
and the brake of the motors is released through the controller of the mechanical arm, so that the arm rod assemblies are allowed to keep a linear serial horizontal state after being limited by the clamp.
5. The method according to claim 1, wherein the step S40 includes:
s41, configuring according to the sequence, triggering and controlling the armature current of each motor, and starting to reset the mechanical arm;
s42, periodically acquiring a feedback signal of the armature current of the driving motor through a Hall element;
and S43, when the driving current rises and approaches to the driving current threshold, based on a current loop control law, performing proportional-integral feedback control on the driving current to enable the driving current to be stabilized at the driving current threshold so as to realize the reset of the mechanical arm.
6. The method according to claim 5, wherein the step S41 further comprises:
every three ropes are arranged in the mechanical arm to control the rotation angle of the joint of one section of arm rod assembly;
and each driving rope is sequentially pre-tightened and reset in a segmented mode according to the sequence from the driving box base to the tail end of the mechanical arm.
7. The method of claim 5, wherein the motor is a DC motor, the step S43 further comprises:
when the average value of the driving current acquired continuously for multiple times reaches a driving current threshold value of 0.2 times, judging that the driving current is close to the threshold value sufficiently;
and introducing the following current loop control equation to perform proportional integral feedback control on the driving current:
Figure FDA0002948005270000021
wherein u isaIs the armature voltage of the DC motor, KiIs a constant much greater than 1, TaIs the electromagnetic time constant of the motor, euFor motor input voltage uiAnd a feedback voltage uaThe difference between the difference of the two phases,
eu＝ui-ua＝ui-iaγ；
wherein u isiFor input voltage, iaGamma is the feedback coefficient of the hall element for the armature current.
8. The method according to claim 5, wherein the step S43 further comprises:
when the drive current is detected to be close to the drive current threshold value, the input voltage u of the motor is controlled according to the following formulaiSo that the armature current iaStabilizes around the threshold value at an exponential rate for a finite time of multiple time constants:
Figure FDA0002948005270000022
wherein T is a control period, τuIs a time constant, uthr＝ithrRaIs equal to the current threshold ithrCorresponding voltage threshold value, wherein RaIs the internal resistance of the motor.
9. A computer readable storage medium having stored thereon program instructions which, when executed by a processor, implement the method of any one of claims 1 to 8.
10. The utility model provides an automatic high accuracy resetting means of flexible arm is driven to rope based on under the frock condition, includes:
the computer-readable storage medium of claim 9;
make the arm pole subassembly of multistage spacing anchor clamps (2) at initial position that resets under the frock condition, anchor clamps (2) are including being used for cup jointing a plurality of location support group frame (21) of the periphery of arm pole and establish ties the cylinder stick (22) of the linear type of a plurality of location support group frame.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114406999A (en) * 2022-02-11 2022-04-29 吉林大学 Rope-driven coaxial artificial muscle actuator and control method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2810745A1 (en) * 2013-03-14 2014-12-10 Rolls-Royce plc Multi-jointed arm assembly
CN106695803A (en) * 2017-03-24 2017-05-24 中国民航大学 Continuous robot posture control system
CN108908333A (en) * 2018-07-13 2018-11-30 华中科技大学 A kind of power position feedback control system for flexible robot
CN108942906A (en) * 2018-08-01 2018-12-07 清华大学深圳研究生院 flexible mechanical arm and system
CN110561401A (en) * 2019-08-14 2019-12-13 哈尔滨工业大学（深圳） Super-redundancy linkage flexible mechanical arm based on closed-loop driving rope
CN111037603A (en) * 2018-10-15 2020-04-21 通用电气公司 Selective flexible extension tool
CN111993400A (en) * 2020-08-11 2020-11-27 哈尔滨工业大学（深圳） Flexible mechanical arm with tail end force feedback

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2810745A1 (en) * 2013-03-14 2014-12-10 Rolls-Royce plc Multi-jointed arm assembly
CN106695803A (en) * 2017-03-24 2017-05-24 中国民航大学 Continuous robot posture control system
CN108908333A (en) * 2018-07-13 2018-11-30 华中科技大学 A kind of power position feedback control system for flexible robot
CN108942906A (en) * 2018-08-01 2018-12-07 清华大学深圳研究生院 flexible mechanical arm and system
CN111037603A (en) * 2018-10-15 2020-04-21 通用电气公司 Selective flexible extension tool
CN110561401A (en) * 2019-08-14 2019-12-13 哈尔滨工业大学（深圳） Super-redundancy linkage flexible mechanical arm based on closed-loop driving rope
CN111993400A (en) * 2020-08-11 2020-11-27 哈尔滨工业大学（深圳） Flexible mechanical arm with tail end force feedback

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114406999A (en) * 2022-02-11 2022-04-29 吉林大学 Rope-driven coaxial artificial muscle actuator and control method thereof
CN114406999B (en) * 2022-02-11 2023-11-21 吉林大学 Rope-driven coaxial artificial muscle actuator and control method thereof

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