CN105643639A - Method for recognizing loads of industrial robot - Google Patents

Abstract

The invention provides a method for recognizing loads of an industrial robot. The method includes the steps that a dynamical equation is input into a dynamics module in a robot controller, and a real-time moment value is obtained; a theoretical current value is worked out according to the real-time moment value; a measured current value and the theoretical current value are compared; if the measured current value and the theoretical current value do not differ much, a motor controls the robot based on a prior control parameter value; and when the measured current value is increased suddenly, the control parameter value of the motor is changed, and the motor controls the robot based on the changed control parameter value. The method can set the control parameters of the industrial robot to be more reasonably under high precision; accordingly, the problem that the regulation time is too long after loads are increased during application of the industrial robot can be solved, and it is ensured that acceleration of the industrial robot has no jerking movement in the moving process.

Description

A kind of industrial robot load torque identification method

Technical field

The invention belongs to robot technology field, specifically, it is a kind of industrial robot load torque identification method.

Background technology

Along with the development of science and technology, robot technology is also in continuous progress, and the Application Areas of industrial robot is also more and more extensive. In the industrial production, industrial robot be widely used in carrying, weld, spray paint, the field such as assembling. When industrial robot is used for different load, owing to the output rating of robot driving device is not mated with load, inevitable to be caused vibrations, causes self wearing and tearing and causing operate miss, the accuracy of reduction robot manipulating task and security of robot.

Summary of the invention

It is an object of the invention to, solve industrial robot and need the problem through multiple middle pose in the application, and the problem excessively grown of regulation time during in order to ensure industrial robot load change be violent in motion, it is proposed that a kind of industrial robot load torque identification method.

For achieving the above object, the present invention is by the following technical solutions:

In robot controlling wherein input power module, solve real-time moment values;

Current value in theory is calculated according to described real-time moment values;

The relatively actual current value measured and theoretical current value;

Current value and the theoretical current value measured if actual are more or less the same, then motor is according to original controling parameters value control;

When the actual current value measured increases suddenly, then changing the controling parameters value of motor, motor is according to the controling parameters value control after change.

Preferably, solve real-time moment values and it is specially: by the angle in each joint that robot finishes the work in process, circular frequency variable quantity, solves real-time moment values.

Preferably, also to comprise described theoretical current value equal with the current value under corresponding attitude for described method.

Preferably, electric machine control parameter is adjusted by the PI parameter value following electric machine control.

The present invention relatively prior art tool have the following advantages: can by under the high precision of industrial robot controling parameters formulate more reasonable, not only can solve industrial robot in the application load increase after the problem excessively grown of regulation time, and ensure that the acceleration of industrial robot in motion is without anxious dynamic.

Accompanying drawing explanation

Fig. 1 is the method flow diagram of the embodiment of the present invention.

Embodiment

Below in conjunction with accompanying drawing and specific embodiment, the technical scheme of the present invention is described in detail.

As shown in Figure 1, being a kind of industrial robot load identification method schema of the present invention, concrete steps are:

S10: in robot controlling wherein input power module, solve real-time moment values.

Concrete, by the kinetic equation of applicable industry robot, input power module in robot controlling device. Being finished the work by robot the angle in each joint in process, circular frequency variable quantity, solves real-time moment values. Kinetics total formula is as follows:

$\left[\frac{f_i}{{\mathrm{\τ}}_j}\right]=I_j^A{\stackrel{\·}{\mathrm{\ξ}}}_j+b_j---\left(1.1\right)$

Wherein, f_jFor the power suffered by the barycenter of each armshaft of six-joint robot, ��_jFor corresponding moment, j is the mark of each connecting rod, and such as, when six-shaft industrial robot, j is 1 to 6.For inertia matrix, b_jFor outer force vector, comprise frictional force, external force and corresponding three-axis force square. Such industrial robot is just defined as the combination of six rigid body motions.

S20: calculate current value in theory according to described real-time moment values.

Current permanent-magnet synchronous motor of a great variety, by the difference in work mains field direction, is divided into radial magnetic field formula motor and axial magnetic field formula motor; By the difference of armature winding position, it is divided into inner rotor type motor and external rotor electric machine; By on rotor with or without starting winding, be divided into without starting winding electric machine and have starting winding electric machine; By the difference of power supply current waveform, it is divided into Rectangular Permanent Magnet Synchronous Motor and sine-wave permanent magnet synchronous motor. The present embodiment is by real-time moment values T_timeBringing the Model in Time Domain of three-phase AC permanent magnet synchronous motor into, described Model in Time Domain is formula (1.2)

$\left[\begin{array}{c}{\stackrel{\·}{i}}_d\\ {\stackrel{\·}{i}}_q\\ {\stackrel{\·}{\mathrm{\ω}}}_m\end{array}\right]=\left[\begin{array}{ccc}-\frac{R}{L}& {\mathrm{p\ω}}_m& 0\\ {-\mathrm{p\ω}}_m& -\frac{R}{L}& {-\mathrm{p\ψ}}_r/J\\ 0& {\mathrm{p\ψ}}_r/J& 0\end{array}\right]\left[\begin{array}{c}{i}_d\\ i_q\\ {\mathrm{\ω}}_m\end{array}\right]+\left[\begin{array}{c}{u}_d/L\\ u_q/L\\ {-T}_L{T}_{\mathrm{time}}/J\end{array}\right]---\left(1.2\right)$

Wherein R is winding equivalent resistance, L_dFor equivalence d axle inductance, L_qFor equivalence q axle inductance, p is motor pole logarithm, ��_mFor rotor mechanical circular frequency, ��_rFor often couple of pole flux W_b, J converts to the total rotational inertia (kg*m^2) on motor shaft, comprises the inertia of motor own and load inertia, and T is the torque (Nm) of conversion to motor total loading. Current value in theory can be obtained: i by formula (1.2)_d, i_q. In general, the current value under current value in theory and corresponding attitude is equal.

S30: compare the actual current value measured and theoretical current value.

S40: current value and the theoretical current value measured if actual are more or less the same, then motor is according to original controling parameters value control.

S50: when the actual current value measured increases suddenly, then change the controling parameters value of motor, motor is according to the controling parameters value control after change.

Concrete, when the actual current value measured increases suddenly, then can judge that the quality of load increases, according to different loads, change corresponding electric machine control parameter value. The PI parameter value that the concrete method changed follows electric machine control adjusts. Scheme is as follows: be below decibel value when zero when closed loop amplitude-frequency characteristic drops to frequency, and corresponding frequency can weigh the stable operation range of three close-loop control, is also the variable range asking for the optimal control parameter of load under different mass. Adjusting electric machine control parameter according to load quality, to adjust electric current loop, the bandwidth of speed ring and position ring and transient state characteristic, ensure that high precision is finished the work, and concrete formula form is such as table 1:

Table 1

When load changes, electric current loop bandwidth, speed endless belt width and position ring bandwidth all change, and cause the scale-up factor of three rings and integral coefficient to change too.

The above embodiment only have expressed several enforcement modes of the present invention, and it describes comparatively concrete and detailed, but therefore can not be interpreted as the restriction to patent scope of the present invention., it is also possible to make some distortion and improvement, it should be appreciated that for the person of ordinary skill of the art, without departing from the inventive concept of the premise these all belong to protection scope of the present invention. Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (4)

1. an industrial robot load torque identification method, it is characterised in that, comprise the following steps:

In robot controlling wherein input power module, solve real-time moment values;

Current value in theory is calculated according to described real-time moment values;

The relatively actual current value measured and theoretical current value;

Current value and the theoretical current value measured if actual are more or less the same, then motor is according to original controling parameters value control;

When the actual current value measured increases suddenly, then changing the controling parameters value of motor, motor is according to the controling parameters value control after change.

2. as claimed in claim 1 a kind of industrial robot load torque identification method, it is characterised in that, described in solve real-time moment values and be specially: by the angle in each joint that robot finishes the work in process, circular frequency variable quantity, solves real-time moment values.

3. a kind of industrial robot load torque identification method as claimed in claim 1, it is characterised in that, also comprise: described theoretical current value is equal with the current value under corresponding attitude.

4. a kind of industrial robot load torque identification method as claimed in claim 1, it is characterised in that, electric machine control parameter is adjusted by the PI parameter value following electric machine control.