JPH01209509A - servo system - Google Patents

Abstract

PURPOSE:To realize the high-speed drive of a servo system with the high frequency characteristics by separating a control circuit part from an amplifier by a changeover switch and actuating the system in an open loop state where no feedback means is used. CONSTITUTION:In case a position control means of a robot, etc., is driven at a high speed by changing the drive performed with the low frequency characteristics secured by a 1st input signal 2 to the drive with the high frequency characteristics, a position detecting signal 10a received from a position sensor 10 connected to said position control means is supplied to a changeover switch 6 via a monitor part 11. Thus a movable contact piece 8 is switched and a 2nd contact B is turned on. Then a control circuit part 1 is separated from an amplifier 9 and an open loop state is secured. A 2nd input signal 7 is directly supplied to the amplifier 9 and the high-speed drive is performed with the high frequency characteristics. In such a constitution, a high-speed drive state is quickly obtained by setting a servo system in an open loop state via the switch 6.

Description

Detailed Description of the Invention: a. Industrial Application Field The present invention relates to a servo system, and in particular, when driven with a normal low frequency characteristic, it is operated in a closed loop state, and when driven with a high frequency characteristic different from the normal one. If so, it involves novel improvements to enable operation in open loop conditions.

b. Conventional technology Various configurations have been adopted for this type of servo system that have been used in the past.To describe a typical configuration, here we will list the names of documents showing the conventional configuration. However, the most commonly used configuration shown in FIG. 3 can be disclosed.

That is, what is indicated by reference numeral 1 in FIG. 3 is a control circuit section into which an input signal 2 is inputted via an adder/subtractor section 3, and an output signal 4 of this control circuit section 1 is used to control the position of a robot, etc. (not shown). input into the means.

A portion 4 & of the output signal 4 is input to the addition/subtraction section 3 via the feedback means 5, and the control circuit section 1 and the feedback means 5 are configured in a closed loop state, so that feedback control is always performed. ing.

Problems to be Solved by the C0 Invention Since the conventional servo system was configured as described above, it had the following problems.

In other words, control is performed in a closed-loop state with the feedback means always activated, so when driving with normal low frequency characteristics, there is no problem, but when trying to rapidly move a moving means such as a robot, for example. If you increase only the drive frequency in a closed loop state,
The followability was poor and it was not possible to drive quickly and with high precision.

The present invention has been made to solve the above-mentioned problems. In particular, when driving with normal low frequency characteristics, it operates in a closed loop state, and when driving with unusual high frequency characteristics, it operates in a closed loop state. The object of the present invention is to provide a servo system which is operated in an open loop state.

61 Means for Solving the Problems A servo system according to the present invention includes a control circuit unit that inputs a first input signal and outputs an output signal while performing feedback control using feedback means, wherein the output side of the control circuit unit This configuration includes a changeover switch provided in the switch, and an amplifier connected to the changeover switch.

80 Effects In the servo system according to the present invention, when driving with normal low frequency characteristics, the control circuit section and the amplifier can be connected by a changeover switch to operate in a closed loop state using feedback means. Can be done.

In addition, when driving with high frequency characteristics different from normal, high-speed driving with high frequency characteristics is achieved by separating the control circuit section and amplifier using a changeover switch and operating in an open loop state without using feedback means. be able to.

Therefore, in normal operation, high-speed tracking is not required, but if high-speed tracking is required for only part of the vehicle, it can be easily achieved by operating the changeover switch.

f. Embodiments Hereinafter, preferred embodiments of the servo system according to the present invention will be described in detail with reference to the drawings.

It should be noted that the same or equivalent parts as in the conventional example will be described with the same reference numerals.

1 and 2 show a servo system according to the present invention, with FIG. 1 being a block diagram showing the overall configuration, and FIG. 2 being a characteristic diagram showing the control state.

Reference numeral 1 indicates a control circuit section into which an input signal 2 is input via an adder/subtractor section 3, and an output signal 1a of this control circuit section 1 is connected to a first contact A of a changeover switch 6. There is.

A second input signal 7 is connected to the second contact B of the changeover switch 6.
A common contact C having a switching contact piece 8 is connected to an amplifier 9, and the output signal 4 of this amplifier 9 is transmitted to a position control means (not shown) of a robot or the like. It is connected to the.

The position control means is provided with a position sensor 10, a position detection signal 10a of this position sensor 10 is applied to a monitor part 11, and a monitor signal 11m from this monitor part 11 is applied to the changeover switch 6. Since the selector switch 6 is composed of an electronic switch,
An electronic switching operation is obtained by switching the movable contact piece 8 (actually composed of an electronic circuit) by this monitor signal 11m.

A portion 4a of the output signal 4 is supplied to the addition/subtraction unit 3 via the feedback means 5, and feedback control is performed.

The servo system according to the present invention is configured as described above, and its operation will be explained below.

First, in the case of driving with normal low frequency characteristics, by switching the movable contact piece 8 of the changeover switch 6 to the position shown by the solid line, the control circuit section 1 and the amplifier 9 are connected, and the servo Since the entire system operates in a feedback-controlled closed loop state, driving based on the first input signal 2 is continued.

Next, if you want to switch from the drive using the low frequency characteristics described above to the high frequency characteristics and drive the position control means (not shown) of a robot or the like at high speed, you can do this manually, but for example, By inputting the position detection signal 10a from the connected position sensor 10 to the changeover switch 6 via the monitor part 11, the movable contact piece 8 is switched from the solid line to the dotted line, and the second contact B is switched from the solid line to the dotted line. When turned on, the control circuit section 1 and the amplifier 9 are disconnected, resulting in an open loop state.

Therefore, the second input signal 7 is directly input to the amplifier 9, resulting in high-speed driving with high frequency characteristics.

After the above-mentioned high-speed drive ends, when returning to the normal low-speed drive state, the changeover switch 6 is switched again based on the position detection signal 10a, the movable contact piece 8 is switched from the dotted line to the solid line position, and again, The first contact A is turned on to return to the low speed drive state due to the low frequency characteristics in the normal state described above.

The aforementioned closed-loop state, open-loop state, and closed-loop state control states are performed as shown in Fig. 2, and when the second contact B is turned on, the state rapidly shifts to the high-speed drive state. It is clear that

g0 Effects of the Invention Since the servo system according to the invention is configured as described above, the following effects can be obtained.

In other words, it is possible to obtain a highly accurate low-speed control state by maintaining a closed-loop servo system with normal low-frequency characteristics, and furthermore, in high-speed drive with high-frequency characteristics, the servo system can be controlled by a changeover switch. By putting the system in an open loop state,
It is possible to rapidly bring the robot into a high-speed driving state, and it is possible to extremely easily perform high-speed positional control of the robot arm, etc., and high-speed positional flyback control of the turntable.

[Brief explanation of the drawing]

1 and 2 are for showing a servo system according to the present invention, and FIG. 1 is a block diagram showing the overall configuration,
FIG. 2 is a control characteristic diagram, and FIG. 3 is a block diagram showing a conventional servo system. 1 is a control circuit section, 1M is an output signal, 2 is a first input signal,
5 is a feedback means, 6 is a changeover switch, 7 is a second
The input signal is an amplifier, 10 is a position sensor, and lla is a monitor signal. Patent applicant: Takushikawa Seiki Co., Ltd. Figure 1 Figure 2

Claims (3)

[Claims] (1) In a servo system having a control circuit section (1) which inputs a first input signal (2) and outputs an output signal (1a) while performing feedback control by a feedback means (5), the control circuit section ( a changeover switch (6) provided on the output side of 1); and the changeover switch (6)
When driving with normal low frequency characteristics, it is operated in a closed loop state using the feedback means (5) and driven with high frequency characteristics different from normal. In this case, the changeover switch (6)
A servo system characterized in that it is operated in an open loop state. (2), the changeover switch (6) has a second input signal (7
) is input, and in the open loop state, the second
2. Servo system according to claim 1, characterized in that the input signal (7) is supplied directly to the amplifier (9). (3) On the output side of the amplifier (9), a position sensor (
10), and the changeover switch (6) is configured to be switched based on a monitor signal (11a) of the position sensor (10). servo system.