SU1657375A1 - Device for manipulator testing - Google Patents

Abstract

Abundance refers to robotics and can be used to create control and diagnostic test benches. The aim of the invention is to expand the functionality of the device by providing greater reliability of control. The device includes pulse shapers, a rectifier, a peak detector, a low-pass filter, a switch, a frequency meter, a timer, a display unit, a fade transducer, a comparators block, and a signal setting unit, which allows an increase in the volume and depth of the control unit. 7 il.

Description

The invention relates to the field of robotics and can be used to create stands for monitoring and diagnostics of a manipulator.

The aim of the invention is to expand the functionality of the device by providing greater reliability of control.

FIG. 1 shows a functional diagram of the device; in fig. 2 is a diagram of a braking pulse initiator; in fig. 4 - scheme of the encoder; Fig. 5 is a diagram of a pulse shaping end driver; figure 6 is a timer circuit; in fig. 7 is a diagram of a braking pulse terminator.

FIG. 1 shows an acceleration sensor 1, a link 2. a manipulator 3, an amplifier 4, a switch 5, a low-frequency filter 6, a frequency meter 7, a transducer block 8 (D / A). comparators block 9, display unit 10, signal setters unit 11, first pulse shaper 12, encoder 13, second pulse shaper 14, timer 15, integrator 16, rectifier 17, comparator 18, first counter 19. peak detector 20, key 21. the second counter 22, the third pulse shaper 23, alarm sensors 24, control unit 25, actuators 26, triggers 27, LEDs 28 and switch 29.

The switch contains {FIG. 2) the element AND 30, the element OR 31, the key 32, the element OR - NOT 33, the keys 34 and 35, the element NAND 36, the key 37 and 38 and the element NOT 39.

The pulse shaper 12 comprises (FIG. 3) a rectifier 39 and a comparator 40.

The encoder 13 (FIG. 4) includes a trigger 41, an OR-NOT 42 element, triggers 43 and 44, an OR-NOT 45 element, and a trigger 46.

The second pulse shaper 14 contains (Fig. 5) a low-frequency filter 47, a detector 48, a one-shot 49 and an AND-HE50 element.

Timer 15 (FIG. 6) includes a trigger 51, element And 52, counter 53, trigger 54, element And 55, counter 56, trigger 57, ele.

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ment And 58, counter 59, generator 60 and single-vibrator 61.

The third pulse shaper 23 comprises (FIG. 7) a detector 62 and an AND-NE element 63.

The device works as follows.

When moving the kinematic link 2 of the manipulator 3 along a given coordinate, there are three characteristic phases of motion: acceleration, the phase of steady-state motion and deceleration.

In this device, the full realization of the acceleration signal sensed by the acceleration sensor 1 during the motion of link 2 is divided into these three phases — acceleration, steady motion and deceleration by determining the times t0, ti, t2, ta, where to is the beginning of the link movement; ti - the end of acceleration - the beginning of the steady-state motion; hl - the end of the steady-state movement - the beginning of braking; ta is the end of braking.

In each of the phases of movement, diagnostic parameters are selected, which are then compared with the maximum permissible values for the healthy kinematic link 2. As diagnostic parameters, peak accelerations are used during acceleration and deceleration, the degree of uniformity of movement in the steady-state phase, the natural frequency of oscillations and the attenuation parameter in the phase braking as well as the duration of the phases of motion.

Information about the passage of the diagnosed kinematic link 2 of the corresponding motion phase is encoded by the encoder 13. At the moment the kinematic link 2 starts to move, the first output of the robot control unit 25 sends a signal 1 (motion start resolution) to the drive 26 of the diagnosed link 2, and the same signal is also fed to the input of the encoder 13. At the moment t0 of the start of movement, the signal 1 is applied to the first descent of the trigger 41 (Fig. 4), which switches at the time t0 and at its output there is a level 1 which enters the input element a AND L AND-NO 42 and the second input of the element OR-NOT 45, which causes a signal O at their outputs corresponding to the acceleration phase (code 00). The signal O from the first and second outputs of the encoder 13 enters the inputs of the switch 5 and switches it in such a way that its input is connected only to the third and fourth outputs. The signal O is received (Fig. 2) at the first and second inputs of the element AND-NO 36, at its output there is level 1, the key 37 is closed. Simultaneously at the exit of the element OR NOT 33

There is a signal 1, which through the element OR 31 closes the key 32, the same signal closes the key 34. The acceleration signal from the first input: the switch 5 passes through the keys 32, 34 and 37 to the outputs of the switch 5.

During acceleration of the link 2 of the manipulator 3 in the phase (to, ti), an acceleration pulse arises, which is detected by the acceleration sensor 1. The acceleration signal from its output goes through the amplifier 4 to the input of the switch 5 and then from its third and fourth outputs to the peak detector 20 and the driver 14 of the acceleration end pulse. Highlighted

5, the peak detector 20, the maximum acceleration value dmakc is a diagnostic sign and is fed through the closed key 21 to the input of the comparators unit 9. Since at time t0 level 1

0 comes from the output of the robot control unit 25 to the input of the encoder 13, i.e. a trigger 46 (FIG. 4), the latter is transferred to state 1 at the output, while the key 21 closes its input to its output. So

5, the maximum peak acceleration value, amax, is fed to the input of the comparator unit 9. The corresponding input of block 9 from block 11 receives a constant threshold voltage corresponding to

0, the maximum allowable acceleration for the controlled link 2. In the event that the value of the max value is exceeded by the threshold value, the comparator of block 9 generates a signal O which goes to the first input trigger 3 of block 27 of the display 10 and switches it to state G. In this case the corresponding LED 28 lights up. Tom. that an excess of the peak value limit

0 acceleration during acceleration of link 2. In the case of a good condition of link 2, the threshold level is not exceeded and the LED 28 does not light up.

Phase of acceleration link 2 manipulator torus 3

5 takes place until the time ti, for which determination the shaper 14 of the acceleration end pulse serves. In the time interval (to, ti) the low frequency filter 47 of the driver 14 (Fig. 5) receives a signal

0 speed up The filter 47 serves to increase the noise immunity of the former 14, has a cut-off frequency of 100 Hz and only passes the signal arising during acceleration of the kinematic link 2. At the output

5 of the low-frequency filter 47, a low-frequency acceleration signal is applied to the detector 48, at the output of which a unipolar Uwyh O signal is generated, indicating that there was movement of the link in the interval (to, ti). This signal

starts the one-shot 49 so that the input element I-NE 50 has a voltage O. The duration of the pulse of the one-shot 49 is known to be greater than the duration of the acceleration phase (to, ti). In this case, by the time tj of the beginning of the steady-state motion, there is a zero voltage at the output of the detector 48, which is fed to the input of the AND-NE element 50, which means that a signal 1 appears at its output, which is fed to the input of the encoder 13 overclocking. The encoder 13 at the same time will form a code (01) corresponding to the phase of steady motion. At the moment the level G arrives (Fig. 4), the first input of the trigger 43 from the driver 14 of the acceleration end pulse at the output of the trigger 43 appears level 1 (Fig. 5). The trigger 41 is set to the state O at the output, at the output element IL AND NO 42 there is a signal O, and the output of the element OR NOT 45 is a signal 1. Thus, code 01 is formed on the entire interval (t /, Td) of the steady-state phase: At the second input of switch 5 there is a level O, and at the third input-level 1. In this case, the switch 5 connects the first input to the second output. The second key is closed and the acceleration signal from the first input of the switch 5 is fed to its second output and then to the integrator 16 and the driver 12 of the start of deceleration pulse.

In the interval (t 1, t2) of the steady-state motion, the diagnostic sign is the uniformity of the speed of the link 2 of the manipulator 3. The integrator 16 forms a signal proportional to the variable speed component from the acceleration signal

U 4- / a (t) dW (t),

1 with where a (t) is the acceleration of the link.

Rectifier 17 performs the operation of taking a module over the signal U. There is a positive pulsating voltage at its output. This voltage is fed to the input of the comparator 18, at the input from block 9 of which the maximum allowable threshold value Unopor 1 for speed unevenness is set.

The Unopor threshold value is supplied as a constant voltage from the output of the threshold unit 11 and has a different value for each link of the robot.

In the case of uneven movement of the diagnosed link 2 of the manipulator 3, the velocity signal surges for the Unopori value are observed. Then, at the moment when the threshold value is exceeded, voltage pulses appear at the output of the comparator 18 in accordance with the formula

/ 1 with Uewnp Unopori;

UeblX.KOMn ™ L

 0 with UBbinp Unopori.

The first counter 19 counts the number n of pulses with level 1. The value n is fed in a binary parallel course to the input of block 8 of the D / A converter. At the output of the corresponding digital-to-analog converter of block 8, a constant voltage is generated, which is fed to the input of the comparator of block 9. It compares with the threshold value of the signal coming from block 11. If the voltage is exceeded by a constant voltage, the comparator 9 ignites the corresponding LED 28. The reset of the first counter 19 is made by a voltage drop arriving at its input at the time ti of the end of the acceleration phase from the output of the driver 14 of the acceleration end pulse. At the same time, before the next phase of steady motion, the first counter 19 is zeroed and ready for counting.

The moment t2 of the end of the steady-state motion phase is determined by means of the driver 12 for the start of braking. At time t2, the link 2 of the manipulator 3 brakes, an acceleration pulse appears (Fig. 3), which is fed to the rectifier 39. It allocates the magnitude of the acceleration pulse value (since azmax can be positive and negative depending on the direction of forward movement or back), which is fed to the input of the comparator 40. The threshold voltage Unopor.-z comes from the output of block 11 to the other input of the latter. The threshold voltage Unopor.g. has a certain value for each kinematic link 2. At the time of exceeding the threshold value Unopor.2. IMPULSE 32max NE OUT6

the comparator 40 forms a voltage drop corresponding to the moment 2 of the start of braking. This difference is fed to the input of the encoder 13 In this case, the encoder 13 at the time t2 generates a code (10) corresponding to the phase of braking. Level 1 is fed to the input of the trigger 44 (Fig. 4), in which level 1 appears at the output, which causes the flip-flop 43 to be thrown to the O position at the output. In this case, the first output of the encoder 13 has a level 1, and the second, O. This code goes to the inputs of the switch 5 and switches it in such a way that the input signal goes to the first and third outputs only (output element 30) (Fig. 2 ) there is 1, the keys 32 and 35 are closed).

The acceleration signal is fed to the low-frequency filter 6 and the peak detector 20. The latter highlights the maximum acceleration E2max in the deceleration section, which enters the key 21 input. Because in the deceleration phase at time t2, the differential from the output of the arrester 12 begins the deceleration of the deceleration to the trigger 46 (Fig. 4), it enters the state O and switches the key 21 so that the input of the corresponding comparator of block 9 receives the acceleration signal E2max. At the second input of this comparator unit 9, a constant voltage from the potentiometer of the unit 11 is set, corresponding to the limit value of the acceleration in the deceleration phase.

From the output of the low frequency filter b, the signal goes to a frequency meter 7, which determines the frequency of the main resonance F, which characterizes the stiffness properties of link 2 of the manipulator 3. When the technical condition deteriorates (bearing breakage, plastic deformation, wear), the rigidity decreases, which is fixed by decreasing F The magnitude of the frequency F in the code goes from the first output of the frequency meter 7 to block 8, where it is converted into a constant voltage. Comparison of this voltage with the threshold occurs in the comparator of block 9. If the value of F is less than the threshold value, then the corresponding trigger 27 lights the LED 28, indicating a malfunction.

From the output of the frequency meter 7, the second counter 22 receives impulses corresponding to the period of natural oscillations of the link

2 manipulator torus T0 -F Second counter 22

calculates the number of m total periods, which characterize the degree of damping of the manipulator 3 (it depends on the technical state of the fixing elements, couplings, brakes, and other elements). The value of m in the code goes to the DAC of block 8, where it is converted into a constant voltage, which in the corresponding comparator of block 9 is compared with the threshold voltage. If the threshold value m is exceeded, the corresponding LED 28 lights up.

Resetting the second counter 22 and the frequency meter 7 is performed by a voltage drop arriving at the second inputs at the time ti of the end of the acceleration phase from the output of the driver 14 of the acceleration end pulse. Moreover, before each next phase of deceleration, the counter 22 and the frequency meter 7 are zeroed.

The moment 1 of the end of the movement of the link is determined by the shaper 23 of the stop braking pulse. The signal from the output of the low frequency filter b is fed to the detector 62 of the generator 23 (Fig. 7). At the end of the oscillations of link 2, the output voltage of the filter 6 is zero and is applied to the input of the AND-NE element 63. To eliminate the false triggering of the driver 23 with unprogrammed link stops at its input, i.e. The input of the NE-NE element 63. also receives a signal O from the setpoint adjuster 24 of the end position, indicating that the link 2 is in the end position.

The execution time of a separate motion phase is also a diagnostic feature of link 2 of the manipulator 3. Therefore, the timer 15 serves to monitor the phases of motion in duration. At its inputs, pulses are successively received at the corresponding times, ti, t2, t3. At the moment to from the output of the robot control unit 25, a voltage drop occurs

5 at the beginning of the movement of the link 2, at the time ti - the signal 1 from the driver 14 of the acceleration end pulse, at the moment t2 - the signal 1 from the generator 12 of the start of the deceleration pulse, at the moment t3 the signal 1 from

0 shaper 23 of the pulse termination stop. At the moment to, the voltage drop is fed to the input of the trigger 51 (Fig. 6) and the one-shot 61. The output of the one-shot 61 produces a short pulse, which resets the counters 53, 56 and 59, and the output of the switch 51 is set to 1.

At the moment tf of the end of the acceleration, the input of the timer 15 receives T from the former 14 of the end of the acceleration. With this trigger 51

0 generates output O, and the second trigger 54-1. A rectangular impulse (t0. Ti), specifying the duration of the counting, arrives at AND 52, which is filled with pulses from a generator 60 counting

5 pulses The number of pulses counted by counter 53 is directly proportional to the interval duration (to, ti). Similarly, the remaining two channels of timer 15 work, measuring the duration of intervals (ti. Ta), (t2, ta), corresponding to the phases of steady motion and braking. From the outputs of counters 53, 56 and 59, the magnitude of the duration of the acceleration phase (to, ti), the phase of steady-state motion (tj, t) and phase

5 braking (ta, ta) in the code goes respectively to the DAC of block 8, the output of which produces constant voltages coming to the first inputs of the comparators of block 9. If the duration of a phase exceeds the threshold value set in block 11, it works the corresponding comparator of block 9 and the LED of block 10, which corresponds to the phase of the movement, illuminates, which indicates a malfunction.

Thus, after the end of the motion of link 2, the obtained values of the diagnostic features: peak accelerations E1max and E2max, the magnitude of the resonance frequency F, the number of oscillation periods m, the magnitude n, which characterizes the motion uniformity and duration of the phases (to, ti), (ti, ta), (t2, 1h) are compared with the maximum permissible, and the result of the comparison is displayed on the display unit 10. Based on the analysis of its state, a decision is made about the health or malfunction of the kinematic link 2, in block 11 new thresholds are set and the key 38 is briefly closed, all the triggers 27 are triggered and all the LEDs 28 go out.

Sensor 1 is mounted on the next diagnosed link 2 so that its axis of sensitivity coincides with the direction of its movement. The input of the deceleration pulse shaping unit 23 is connected, for example, to the sensor 24 of the end position of this link 2. The input of the encoder 13 is connected to the input of the drive 26 of the specified link 2, the diagnostics of which are carried out in a similar way.

Claims (1)

Invention Formula A device for controlling the manipulator, containing a control unit, the outputs of which are connected to the actuator input of the manipulator links, and the inputs to the output of the position sensors, an acceleration sensor connected to the amplifier input, connected in series to the amplifier input, connected in series to the comparator and the first counter, as well as The second counter, key and integrator, characterized in that, in order to expand the functionality of the device by providing greater reliability, control, it further comprises an ind block katsii block comparator unit setting devices a signal, a transducer block, three formers, a pulse generator, a rectifier, a peak detector, a timer, an encoder and a serially connected switch, low frequency filter and frequency meter, the first output of which is connected to the first input of the second counter, and the second output to the first input of the converter unit connected by the second input to the output of the first counter, the third input to the output of the second counter, fourth, fifth and sixth inputs with the timer outputs, and six outputs with the corresponding inputs of the comparators block, the seventh and the eighth inputs of which are connected respectively to the first and second outputs of the key, the inputs from the ninth to the sixteenth - respectively to the outputs from the first to the eighth block of signal setting devices, and the outputs - to the corresponding inputs of the display unit, the first key input is connected to the output of the peak detector, and the second input is connected to the first output of the encoder connected by the first, second and third inputs to the corresponding inputs of the timer and to the output of the corresponding driver of the pulse, the fourth input to the corresponding input of the timer and one of the outputs of the control unit, and the second and third outputs, respectively, to the first and second inputs of the switch, the third input of which is connected to the output of the amplifier, the second output to the input of the peak detector a, the third output - with the input of the integrator and the first pulse generator, and the fourth output - with the input of the second pulse generator, connected by the output to the second input of the first and second counters and frequency meter, the integrator output is connected to the first input of the comparator through the rectifier, the second input of which is connected to the ninth output of the signal adjuster block, connect a little tenth output to the second input of the first pulse shaper, the output One of the addition sensors is connected to the first input of the third pulse shaper, the second input of which is connected to the output of the low-frequency filter. Drive unit From the 1st Output of the J3 Encoder At the input of filter 6 On Log in (pegro 1ka 20 Zlaka U  From the 2nd Cipher / POR Output / J Fig2 Fig.Z -TO L. 47 40 FIG A B W 50 -J FIG. five FIG. 6 7 On the DAC 8L On the DAC 8.5 NACAP D 8.6 From 2 Exit SAOKU 25