JPS63170706A - Robot controller - Google Patents

Abstract

PURPOSE:To avoid a danger due to trouble of a target speed signal generating part by outputting a speed command signal from a speed operating part or a second speed operating part to set the speed of an actuator to zero when an abnormality signal is outputted from a speed abnormality detecting part. CONSTITUTION:The speed of the actuator is monitored by a speed abnormality detecting part 24, and an abnormality signal 23a is outputted from the speed abnormality detecting part 24 if the speed of the actuator is on the outside of a speed range limited by upper and lower limit speed signals 19a and 19b. Then, the input of a target speed signal 10a to a speed operating part 18 is cut off by a gate circuit 25 if the gate circuit 25 exists, and only position change signals 6a and 6b are inputted to the speed operating part 18. If the gate circuit 25 does not exist, the abnormality signal is inputted to the second speed operating part 27. Consequently, a speed command signal 16a is outputted from the speed operating part 18 or the second speed operating part 27 to set the speed of the actuator to zero. Thus, a danger is not caused even in case of trouble of a target speed signal generating part 14.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a robot control unit that automatically moves a driven object using a computer or the like, so that the driven object will run out of control even if an abnormality occurs in the Regarding the control device that never happens
Ru.

[Conventional technology]

FIG. 5 is a configuration diagram of a conventional robot control device. In the figure, reference numerals 1 and 2 are servo motors as actuators that drive the arm and arm l of the robot, respectively, and the motor 2 has Vc so as to drive the arm l as an object to be driven in accordance with the input H and B drive signals 3. It is 1 color. 4 is a pulse encoder that is directly connected to the motor 2Vc and outputs one pulse for each predetermined angle of rotation when the motor 2 rotates; 14 at! This is a pulse signal output by the pulse encoder 4. Since the pulse signal 4a is a signal output as described above, it is a signal corresponding to a change in the rotational position ta of the motor 2, and hereinafter this signal may also be referred to as a position change signal. 5 receives the pulse signal 4a, and when the signal 4a is a signal based on the forward rotation of the motor 2, the signal 4a is outputted from the first output terminal 5a as a position change signal 6a, and the signal 4a is based on the reverse rotation of the motor 2. When the signal is &1, the rotation direction determining unit outputs the signal 4a from the second output terminal 5b as the position change signal 6b,
Reference numeral 7 denotes an F/V conversion section which receives signals 6a*6b and outputs an analog voltage signal 7a corresponding to the pulse frequency of these input signals as an actual speed signal. signal 7
Since a is a signal output as described above, it is a signal corresponding to the rotational speed of the motor 20. In this case, the signal 7a is configured to have positive or negative polarity depending on whether the motor 2 rotates forward or backward. ing.

Reference numeral 8 denotes a driving state detecting section in which the pulse encoder 4, rotational direction determining section 5, and F/V converter's7 are connected as shown in the figure. , detects the driving state of the motor 2 with respect to the arm lVc, and generates an actual speed signal 7a corresponding to the rotational speed of the motor 20 and a position change signal 6a corresponding to a change in the rotational position of the motor 2.
*Rb.

Reference numeral 9 denotes a control unit which outputs an operation instruction signal 9a specifying the operation mode such as operation speed, movement ik, and direction of movement of the arm l according to a predetermined program; and 10, when the command signal 9a is input, a control unit outputs an operation instruction signal 9a that specifies the operation mode such as the operation speed, movement ik, and movement direction of the arm l; For example, a pulse train signal having a temporal pattern as shown in FIG.
This is a pulse generating section that outputs a target speed signal 10a of , and a binary signal lOb representing the rotation direction of the motor 20. The vertical axis in FIG. 6 indicates the target rotational speed of the motor 2 using the frequency of pulses in the signal IQaK, and the area S of the portion surrounded by the characteristic @tOa and the time axis in FIG. shows the target rotation angle. The frequency of the pulses in the signal toaic corresponds to the operating speed of the arm l, the signal 10b corresponds to the direction of movement of the arm l, and the aforementioned area S corresponds to the amount of movement of the arm l.

11 is an inverter circuit for inverting the value of the binary signal lOb; 12 is a two-person AND circuit to which the signals 10a and 10b are input; and 13 is a two-person AND circuit to which the signal 10a and the output signal of the inverter 11 are input. , 12ae13at
z are respective output signals of AND circuits 12 and 13, respectively.

14 is a target speed signal generation section consisting of a pulse generation section 10, an inverter circuit 11, and an AND circuit 12.13; in this case, when the signal 10b represents the forward rotation of the motor 2, the target speed signal tOa is output from the AND circuit 12; When the signal 10b indicates the reverse rotation of the motor 2, the AND circuit 13 outputs the signal 10a at a ratio of L° C. to the output signal 13a.

Therefore, the generation unit 14 generates a target speed signal tO in a time-lapse pattern based on the 1 failure force information to which the operation command signal 9a is input.
This means that it outputs an a.

15 additively counts the number of Vc pulses inputted to the input terminal 151 or 153, and
When a 52 or 1541C pulse is input, the number of the pulses is counted subtractively, and the resultant count value, which is equal to the algebraic sum of the above-mentioned additive count value and subtractive count value, is tabulated.
16 is a D/A converter which converts the signal 15a7S' into an analog electric signal t6a and outputs it in degrees Celsius. 17 to engineering information number 16a and 7a
This is a servo amplification section which receives the input signal 7a and outputs the drive signal 3 to drive the motor 2 so that the value of the signal 7a matches the value of the signal 11'ia. Since the signal 7a represents the rotational speed of the motor 2, the motor 2 is eventually connected to the amplifying section 17Vc.
Therefore, the rotational speed should be controlled to the value indicated by the signal 1f'ia. In other words, the signal 1fiaf2 is a related command signal that commands the rotational speed of the motor 2. In FIG. 5, signals 12al 13a# 616a are input to each of the input terminals 151 to 154 of the addition/subtraction section 15, respectively. Then, as mentioned above, signal 1
2a, 13at? Signals 6a, t') and t) correspond to forward and reverse rotation of motor 2, respectively.
This is a signal that is output in degrees Celsius depending on the forward or reverse rotation of the motor. Further, the speed command signal 11'ia is a signal obtained by converting the output signal 158 of the addition/subtraction section. Therefore, in FIG.
and the D/A father exchange section 16, target speed signals 12a and 13a
and compliment change signals @6a, Rb are input, and constitute a speed calculation unit 18 which performs predetermined calculations on these input signals and outputs a speed command signal 1fSa according to the calculation result. can.

In FIG. 5, each part is configured as described above, so that in response to the command signal 9a, for example, the target speed signal 10a of the temporal pattern shown in FIG. , servo amplifier section 17
A speed command signal 11'ia having a value corresponding to the time integral value of the signal 12a is input to the motor 2, and the motor 2 rotates in the forward direction so that the rotational speed corresponds to the value of the signal 1fia. However, when the motor 2 rotates in the normal direction, the position change signal 6a accompanying the normal rotation of the motor 2 is input to the addition/subtraction unit I5, so that the speed command signal 1fia is a signal having the same temporal pattern as the temporal pattern in FIG. 6. becomes. Therefore, the motor 2 rotates in the normal direction according to the target speed signal 10a, and eventually the arm l
is operated based on the command signal 9avc. When the control unit 9 outputs the signal 9a instructing the motor 2 to reverse rotation, the motor 2 performs the reverse operation according to the signal 9alC in the same way as above. do.

[Problems to be Solved by the Invention] In FIG. 5, since the robot control device is configured as described above, each part is normal and the motor 2 moves as instructed by the operation command signal 9aVc. l: However, if the pulse generator IO fails and a signal 10a with an abnormally high pulse frequency is output from the pulse generator IO, the motor 2 will operate according to this signal lOa, resulting in runaway. In addition, in FIG. 5, there is no means provided to prevent the signal 10a of such a pulse frequency from being input to the addition/subtraction section 15. Therefore, the above-mentioned robot control device This is because no means is provided to prevent the target speed signal 10a having an abnormally high pulse frequency from being output from the pulse generator 10 when a failure occurs in the pulse generator 10.

Pulse generator! If the motor 0 breaks down, there is a risk that the motor will run out of control, which poses a problem in that it is dangerous to handle.

The object of the present invention is to obtain a robot control device that is free from danger by preventing the motor 2 from running out of control even if a failure occurs in the pulse generator lO and a signal tOa with an abnormally high pulse frequency is output. It is in.

[Means for solving problems]

According to the present invention, VC1 solves the above problems.

a control unit that outputs a motion command signal that specifies the motion mode of a driven object according to a predetermined program; and a target speed signal generator that outputs a target speed signal of a temporal pattern based on the input signal when the motion command signal is input. an actuator that drives the driven object according to an input drive signal; and an actuator that detects a driving state of the actuator with respect to the driven object and generates an actual speed signal corresponding to the speed of the actuator and a position of the actuator. a drive state detection unit that outputs a position change signal according to a change in the drive state;
When the target speed signal and the position change signal are input, a predetermined calculation is performed on the meat input signal, and a speed command signal is output in accordance with the result of the engineering calculation.

And the input of the target speed signal is cut off, and the worker position it<
a speed calculation unit that outputs the speed command signal so as to stop the actuator when only the f ratio signal is input; and a speed control section that outputs the drive signal so that the foot reaches a speed corresponding to the speed command signal.

In the device for causing the driven object to operate according to the operation command signal, when the operation command signal is input, an upper limit speed signal and a lower limit speed signal each having a temporal pattern corresponding to a temporal pattern of the target speed signal are generated. and a limit speed signal generation section to output.

the upper and lower limit speed signals and the actual speed signal are input; and an abnormality detection unit is configured to output an abnormality signal when the speed of the actuator reaches a speed outside the speed range limited by the upper and lower limit speed signals. Further, when the target speed signal is input between the target speed signal generation section and the speed calculation section and the abnormal signal is not input, the target speed signal is passed through, and when the abnormal signal is input, the Either a gate circuit that blocks passage of the target speed signal is interposed, or the target speed signal and the position change signal are inputted, and a predetermined calculation is performed on the meat input signal to specify the speed according to the calculation result. The robot control device can be improved by providing a second speed calculation unit in place of the speed calculation unit, which outputs a signal and also outputs the speed command signal so as to stop the actuator when the abnormal signal is input. shall be configured.

[Effect]

If the robot control device is configured as described above, if the target speed signal generation section fails and a target speed signal with an abnormally large value is output from the generation section, this signal will be Through this circuit, if there is no gate circuit, the speed calculation sVc is input directly from the target speed signal generation section, so the actuator tries to reach an abnormally large speed indicated by the target speed signal.However, the speed of the actuator is abnormally high. It is monitored by the detection section, and when the speed of the actuator 21 goes outside the speed range defined by the upper and lower limit speed signals, an abnormality signal is output from the speed abnormality detection section.Then, the gate circuit is activated. In this case, the input of the target speed signal to the speed calculation section is cut off by the gate circuit, and only the position change signal is input to the work speed calculation section.If there is no gate circuit, VC will receive an abnormal signal. will be input to the second speed calculation section, so in the former case, the speed calculation section will issue a speed instruction to bring the actuator's speed to zero, and in the latter case, the speed instruction will be issued from the second speed calculation section to bring the actuator's speed to zero. A signal is output.Therefore, the actuator is stopped without running out of control.Therefore, even if the I-work target speed signal generation section of such a robot control device fails, there is no danger.

〔Example〕

FIG. 1 is a block diagram of a first embodiment of the present invention.

In FIG. 1, reference numeral 19 denotes a limit speed signal generation unit which outputs an upper limit speed signal 19a and a lower limit speed signal 19b, each having a temporal pattern corresponding to the temporal pattern of the target speed signal 10a, when the operation command signal 9a is input. , signal 19
Both a and 19b are analog voltage signals.

Next, the function of the signal forming section 190 will be explained in more detail with reference to FIG. That is, Q22 in FIG. 2 is a temporal pattern of the basic voltage, and this pattern corresponds to the temporal pattern of the target speed signal 10a shown in FIG. now,
Assuming that the control section 9 outputs the command signal 9a, and as a result, the pulse generation section 10 outputs the signal 10a having the temporal pattern shown in FIG. Voltage signal 19a of the shown temporal pattern
The VC is configured to output +19b. signal 19
When the voltage of the basic voltage 22 is V, a is a voltage having a value of (V+A), and the signal 19b is a voltage having a value of -(V+8). Here, both A and Bt'x are constant positive values, and ■ is also a voltage with positive polarity. Therefore, if a command signal 9a is output from the control section 9 and this signal 9a is a signal commanding the motor 2 to have a speed according to the time pattern shown in FIG. Regardless of which direction the reverse direction is given, the signal generation unit 19 generates a signal t9a*19 having the temporal pattern shown in FIG.
b will be output.

Referring again to FIG. 1, 'c71°20 receives the upper limit speed signal 19a and the actual speed signal 7a, and when the voltage of the signal 19a is higher than the voltage of the signal 7a, the output signal 20a is set to H.
level, and when the levels of both input voltages are reversed, output signal 2
The first comparator which sets 0a to L level, 21 signal 7a and lower limit speed signal 19b are input. If the voltage of t1 signal 7a is higher than that of signal 19b, the output signal 21a becomes YH level and the voltage of signal 19b becomes the signal. 7a, the second comparator sets the signal 21a to L level; 23 is the signal 2;
This is an AND circuit which outputs a signal 23ail'H level when 0a and 21a are input and both input codes are at IcH level. Reference numeral 24 denotes a speed abnormality detection section consisting of comparators 20 and 21 and an AND circuit 23. Since the detection unit 24 has the VC configuration as described above, if the voltage of the signal 7a does not change over time as shown in FIG. 3, the AND circuit 2
The output signal 23a of No. 3 changes VC as shown in FIG. The signal 73GC is a signal representing the rotational speed of the motor 2 as described above. Shikatsu''C, signal 19a
If the voltage of signal 19b is set to correspond to the forward rotation limit speed of motor 2 and the voltage of signal 19b is set to correspond to the reverse rotation limit speed of motor 2, the level of output signal 23H will be set to correspond to the speed of motor 2. When the speed exceeds the speed range defined by the signals 19a and 19b, it becomes L level.

In such a case, it is clear that the speed of the motor 2 is abnormal. In Figure 1, signal 193.1
9b are the forward rotation limit speed and reverse rotation limit speed f of the motor 2, respectively.
Since the signal is set to correspond to K, 24
The speed signals 19a, 19b, and 7a are input to the motor 2.
It can be said that this is a speed abnormality detecting section that outputs the L level signal 23a as an abnormal signal when the speed of the motor is outside the speed range defined by the signals 19a and 19b.

25 has two input terminals 251 and 252 and two output terminals 253 and 254, and when the input signal 23a becomes H level, the gate becomes open, and when the signal 23a becomes L level, the gate becomes closed. In the gate circuit, the signals i2a*13a that are input to the gate circuit 25 and the input terminals 251 and 252, respectively, are passed through as they are when the gate is open, and output signals 25a and 25b are output from the output terminals 253 and 254, respectively. When the gate is closed, the signal 12al13H is output as follows. Then, in FIG.
It will be necessary for Natsuko to input the following.

The robot system (i!4I system a in Figure 1) has each part configured as described above, so the speed of the servo motor 2 is controlled by the signal 1.
When the speed is within the speed range defined by 9a and 19b, the gate circuit 25 is in an open state. Therefore, does the motor 2 operate according to the instruction signal 9a? do. However, if a failure occurs in the pulse generator 10 and the signal 12a or 138 becomes a signal with an abnormally high pulse frequency,
In response to this signal, the speed of the machine motor 2 becomes abnormally large, and as a result, the speed abnormality detection section 24 outputs an L level signal 23.
a is output. Therefore, the gate circuit 25 is in a closed state, and the pulses input to the input terminals 151 and 152 of the addition/subtraction section become zero. However, since the motor 2 is still rotating in the direction of rotation when its speed became abnormal, the addition/subtraction unit 15 Vc'lcEkel/"e/lzs.

The count will eventually reach zero. Therefore, the speed calculation section 18
From there, a signal having a value corresponding to the count content of zero in the addition/subtraction section 15 is outputted as a speed command signal 1fia. The main parts are constructed so that the value of the signal 1fia at this time is 100, which commands the motor 2 to have zero speed. Therefore, when the gate circuit 251CL level signal 23a is input, the speed of the motor 2 gradually decreases and eventually stops. Therefore, in the case of FIG. 1, even if a pulse generation@10K failure occurs and the target speed signal 10a with an abnormally high pulse frequency is output from the core, the motor 2 will not run out of control.

FIG. 4 is a configuration diagram of a second embodiment of the present invention, and the difference from FIG. 1 is that the gate circuit 25 is omitted;
An addition/subtraction section 26 corresponding to the addition/subtraction section 151C is provided. 2fil to 264 are input bubbles corresponding to the input terminals 151 to 154 of the addition/subtraction unit 150, respectively;
The addition/subtraction unit 26 has terminals 26.1 to 2fi4Vc1 12.
When a, 13a* 6b*6a is input, the addition/subtraction unit 15
In addition to being configured to perform a counting operation similar to the above and outputting the signal 15a, it is also configured such that when the L level signal 23a is input to the clear terminal 26a, the counted contents are forcibly set to zero. There is. Therefore, also in Figure 4.

When the speed of the motor 2 abnormally increases as a result of a failure in the pulse generator 10 and the abnormality signal 23a at the L level is output from the speed abnormality detection section 24, the motor 2 becomes stopped. In other words, even in this case, the motor 2 will not run out of control. Reference numeral 27 denotes a second speed calculation section consisting of an addition/subtraction section 26 and a D/A conversion section I6.

In each of the embodiments described above, the pulse encoder 4 is of an incremental type, but in the present invention, the pulse encoder 4 may be of an absolute type.

〔Effect of the invention〕

As described above, one aspect of the present invention includes a control unit that outputs an operation command signal specifying the operation mode of a driven object according to a predetermined program, and a control unit that outputs an operation command signal that specifies the operation mode of a driven object according to a predetermined program, and a control unit that outputs an operation command signal that specifies the operation mode of a driven object, and when the operation command signal is input, A target speed signal generation unit that outputs a target speed signal of a pattern, an actuator that drives an object to be driven according to an input drive signal, and a drive state of the actuator with respect to the object to be driven is detected and the speed of the actuator is adjusted according to the speed of the actuator. A drive state detection unit outputs an actual speed signal and a position change signal corresponding to a change in the position of the actuator, and when the target speed signal and position change signal are input, a predetermined calculation is performed on the meat input signal and the calculation result is a speed calculation section that outputs a speed command signal according to the speed command, and outputs a speed command signal so as to stop the actuator when the input of the target speed signal is cut off and only the position change signal is input; a speed control unit that receives the signal and the actual speed signal and outputs the drive signal so that the speed of the actuator becomes a speed that corresponds to the speed command signal, and causes the driven object to operate according to the movement command signal. A limit speed signal generation unit that outputs an upper limit speed signal and a lower limit speed signal each having a temporal pattern corresponding to a temporal pattern of the target speed signal when an operation command signal is input, and an upper limit speed signal, a lower limit speed signal, and an actual speed a speed abnormality detection section that outputs an abnormal signal when the speed of the actuator reaches a speed outside the speed range defined by the upper and lower limit speed signals; When the target speed signal is input between the target speed signal and the abnormal signal is not input, a gate circuit is inserted between the target speed signal and the target speed signal that passes the target speed signal and blocks the passage of the target speed signal when the abnormal signal is input, or A position change signal is input, a predetermined calculation is performed on the meat input signal, and a speed command signal is output according to the calculation result, and when an abnormal signal is input, a speed command signal is outputted to stop the actuator. , the robot control unit R was constructed by providing a two-speed calculation unit in place of the speed calculation unit. Therefore, in such a robot control device, if the target speed signal generation section fails and a target speed signal of an abnormally large value is output from the generation section, this signal will If there is no gate circuit, the target speed signal is input directly from the target speed signal generation section to the speed calculation section, so the actuator tends to reach an abnormally large speed as indicated by the target speed signal. However, the speed of the actuator is monitored by the speed abnormality detection section, and when the speed of the actuator goes outside the speed range defined by the upper and lower limit speed signals, an abnormality signal is output from the speed abnormality detection section. Then, if there is a gate circuit, the input of the target speed signal to the speed calculation unit is blocked by the gate circuit, and only the position change signal is input to the work speed calculation unit VC, and the gate circuit If not, an abnormal signal will be manually input to the second speed calculation section, so in the former case, vc is input from the speed calculation Ig, and in the latter case, vc is input from the second speed calculation section to the actuator speed. The speed command signal should be output as f' to zero. Therefore, the actuator does not run out of control (does not come to a stopped state).Therefore, the present invention has the advantage that even if the target speed signal generation section fails, there is no danger.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, and FIG. 4 each show a first embodiment of the present invention. It is each block diagram of 2nd Example. FIGS. 2 and 3 are explanatory diagrams of different operations of the main parts in FIG. 1, FIG. FIG. 6 is an explanatory diagram of the operation of the main parts in FIG. 5. l...Arm, 2...Servo motor,
fialfib...Position change signal, 7a...
... Actual speed signal, 8 ... Drive state detection section,
9...Control unit, ga...Operation command signal, ioa...Target speed signal, 14...
...Target speed signal generation unit, 16a... Speed command signal, 17... Servo increase@ section, 18...
...Speed calculation unit, 19...Limit speed signal generation section, 19a...Upper limit speed signal, 19b...
...lower limit speed signal, 23a...output signal,
24...Value degree abnormality detection unit, 25...Gate times %, 27...Second speed calculation unit. Agent J,? Shi Yamaguchi Iwao ρ '11! 2 figure blind 3rg: J pant G[l

Claims (1)

[Claims] a control unit that outputs a motion command signal that specifies the motion mode of a driven object according to a predetermined program; and a target speed signal generator that outputs a target speed signal of a temporal pattern based on the input signal when the motion command signal is input. an actuator that drives the driven object according to an input drive signal; and an actuator that detects a driving state of the actuator with respect to the driven object and generates an actual speed signal corresponding to the speed of the actuator and a position of the actuator. a drive state detection unit that outputs a position change signal according to a change in the drive state;
When the target speed signal and the position change signal are input, a predetermined calculation is performed on both input signals and a speed command signal according to the calculation result is output, and the input of the target speed signal is cut off and the position change signal is changed. a speed calculation unit that outputs the speed command signal so as to stop the actuator when only the change signal is input; and a speed calculation unit that outputs the speed command signal so as to stop the actuator when the speed command signal and the actual speed signal are input, and the speed of the actuator changes to the speed command signal. and a speed control unit that outputs the drive signal so as to make the driven object move in accordance with the movement command signal, wherein when the movement command signal is input, the speed control unit outputs the drive signal so that the drive signal reaches the target speed. a limit speed signal generating section that outputs an upper limit speed signal and a lower limit speed signal having a temporal pattern corresponding to a temporal pattern of the speed signal; a speed abnormality detection section that outputs an abnormal signal when the speed falls outside the speed range defined by the upper and lower limit speed signals; and further, the target speed signal is provided between the target speed signal generation section and the speed calculation section. is input and the abnormal signal is not input, the target speed signal is passed through, and when the abnormal signal is input, a gate circuit is provided that blocks passage of the target speed signal, or the target speed signal and the position are a change signal is input, performs a predetermined calculation on both input signals, outputs the speed command signal according to the calculation result, and outputs the speed command signal to stop the actuator when the abnormal signal is input. A robot control device characterized in that a second speed calculation section is provided in place of the speed calculation section.