JPH0477324B2 - - Google Patents
Info
- Publication number
- JPH0477324B2 JPH0477324B2 JP58226344A JP22634483A JPH0477324B2 JP H0477324 B2 JPH0477324 B2 JP H0477324B2 JP 58226344 A JP58226344 A JP 58226344A JP 22634483 A JP22634483 A JP 22634483A JP H0477324 B2 JPH0477324 B2 JP H0477324B2
- Authority
- JP
- Japan
- Prior art keywords
- stage
- motor
- pulse
- command pulse
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Program-control systems
- G05B19/02—Program-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form
- G05B19/19—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path
- G05B19/21—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an incremental digital measuring device
- G05B19/25—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an incremental digital measuring device for continuous-path control
- G05B19/251—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an incremental digital measuring device for continuous-path control the positional error is used to control continuously the servomotor according to its magnitude
- G05B19/253—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of program data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an incremental digital measuring device for continuous-path control the positional error is used to control continuously the servomotor according to its magnitude with speed feedback only
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/35—Nc in input of data, input till input file format
- G05B2219/35438—Joystick
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/41—Servomotor, servo controller till figures
- G05B2219/41156—Injection of vibration anti-stick, against static friction, dither, stiction
Landscapes
- Engineering & Computer Science (AREA)
- Human Computer Interaction (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Control Of Position Or Direction (AREA)
- Control Of Velocity Or Acceleration (AREA)
- Control Of Electric Motors In General (AREA)
Description
【発明の詳細な説明】
（発明の技術分野）
本発明は、直流モーターによるステツプ駆動法
を用いたステージの速度制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a stage speed control device using a step drive method using a DC motor.
（発明の背景）
直流モーターによるステツプ駆動法を用いたス
テージの速度制御装置は、ステージの移動距離に
応じた数の指令パルスを偏差カウンタの一入力端
子に入力し、該偏差カウンタの他入力端子に直流
モーターの回転軸に結合したロータリーエンコー
ダからのフイードバツクパルスを入力せしめ、偏
差カウンタの出力をデジタル・アナログ変換器
（以下、Ｄ／Ａ変換器と称す）にてアナログ信号
に変換した後、増幅器等を介して直流モーターを
駆動する如き構造のものであつた。そして、この
ような装置では、指令パルスの周波数が一定の場
合、直流モーターの速度変化量は、１パルスあた
りのステージの移動量と比例しており、ステージ
の速度変化量を小さくするためには、１パルスあ
たりの移動量を小さくしなければならず、そのた
めには、ロータリーエンコーダの分解能を高める
必要があり、コストアツプにつながるという欠点
があつた。(Background of the Invention) A stage speed control device using a step drive method using a DC motor inputs a number of command pulses corresponding to the moving distance of the stage to one input terminal of a deviation counter, and inputs a number of command pulses corresponding to the moving distance of the stage to one input terminal of the deviation counter. After inputting the feedback pulse from the rotary encoder connected to the rotating shaft of the DC motor, and converting the output of the deviation counter into an analog signal using a digital-to-analog converter (hereinafter referred to as a D/A converter), The structure was such that a DC motor was driven through an amplifier or the like. In such a device, when the frequency of the command pulse is constant, the amount of change in the speed of the DC motor is proportional to the amount of movement of the stage per pulse, and in order to reduce the amount of change in stage speed, , the amount of movement per pulse must be reduced, and for this purpose it is necessary to increase the resolution of the rotary encoder, which has the disadvantage of increasing costs.
（発明の目的）
本発明はこれらの欠点を解決し、１パルスあた
りのステージの移動量を小さくすることなく、速
度変化量を小さくすることを目的とする。(Object of the Invention) An object of the present invention is to solve these drawbacks and to reduce the amount of speed change without reducing the amount of stage movement per pulse.
（実施例）
第１図は本発明の一実施例のブロツク図であ
り、指令パルス発生器１から顕微鏡ステージ２の
移動量に対応した数の指令パルスが，所定の周波
数で、偏差カウンタ３の一入力端子に入力され
る。偏差カウンタ３の他入力端子には、ステージ
２を駆動する直流モーター５の回転軸に連結した
回転軸を有する。ロータリーエンコーダ６の出力
するフイードバツクパルスが入力されている。偏
差カウンタ３は、指令パルスの数とフイードバツ
クパルスの数の差に対応した計数値を出力する。
一方、基準パルス発生回路４は、基準パルスを指
令パルス発生器１に入力すると共にのこぎり波発
生器７に入力せしめる。指令パルス発生器１は基
準パルスを分周して指令パルスを出力する。一
方、のこぎり波発生器７は、例えば積分回路によ
つて構成されており、基準パルス発生回路４の出
力するパルスをのこぎり波状に変換して出力す
る。Ｄ／Ａ変換器８は、のこぎり波発生器７のの
こぎり波をゲインコントロール信号としてゲイン
コントロールされる。従つて、Ｄ／Ａ変換器８か
ら出力されるアナログ信号は、偏差カウンタ３の
計数値にゲインコントロール信号を掛けた如き信
号（のこぎり波状）になり、この信号は増幅器９
を通して直流モーター５を制御するために使われ
る。(Embodiment) FIG. 1 is a block diagram of an embodiment of the present invention, in which a number of command pulses corresponding to the amount of movement of the microscope stage 2 are sent from a command pulse generator 1 to a deviation counter 3 at a predetermined frequency. It is input to one input terminal. The other input terminal of the deviation counter 3 has a rotating shaft connected to the rotating shaft of a DC motor 5 that drives the stage 2 . Feedback pulses output from the rotary encoder 6 are input. The deviation counter 3 outputs a count value corresponding to the difference between the number of command pulses and the number of feedback pulses.
On the other hand, the reference pulse generation circuit 4 inputs the reference pulse to the command pulse generator 1 and also to the sawtooth wave generator 7. The command pulse generator 1 divides the frequency of the reference pulse and outputs the command pulse. On the other hand, the sawtooth wave generator 7 is constituted by, for example, an integrating circuit, and converts the pulse output from the reference pulse generation circuit 4 into a sawtooth waveform and outputs the same. The gain of the D/A converter 8 is controlled using the sawtooth wave from the sawtooth wave generator 7 as a gain control signal. Therefore, the analog signal output from the D/A converter 8 becomes a signal (sawtooth waveform) that is the result of multiplying the count value of the deviation counter 3 by the gain control signal, and this signal is outputted by the amplifier 9.
It is used to control the DC motor 5 through.
従つて、第２図ａに示した如き基準パルスが基
準パルス発生回路４より出力されると、指令パル
ス発生器は基準パルスを1/4に分周した第２図ｂ
の如き指令パルスを出力する。その結果、のこぎ
り波発生器７は第２図ｃの如きのこぎり波形を出
力する。それ故、時刻t1で指令パルスが偏差カウ
ンタ３に入力され始めると、偏差カウンタ３の計
数値は１となり、それに対応してＤ／Ａ変換器８
の出力信号は、のこぎり波発生器７ののこぎり波
で変調されて第２図ｄで示した如き最大値V0の、
のこぎり波信号を出力する。この信号は増幅器９
に入力され、のこぎり波状の駆動電圧となつて直
流モーター５に印加されるが、この程度の電圧で
は直流モーター５は回転しない。次に、時刻t2で
指令パルスが入力されると偏差カウンタ３の計数
値は２となり、Ｄ／Ａ変換器８の出力信号は、最
大値2V0の、のこぎり波状信号となる（第２図
ｄ）。この信号は増幅器９を通してのこぎり波状
の駆動電圧となるが、この電圧でも直流モーター
５は回転しない。時刻t3でさらに指令パルスが入
力されると偏差カウンタ３の計数値は３となり、
Ｄ／Ａ変換器８の出力信号は、最大値3V0の、の
こぎり波状信号となる（第２図ｄ）。最大値3V0
は直流モーター５を回転開始するのに十分な信号
となり、直流モーター５は回転を開始する。そし
て、のこぎり波状の駆動電圧で駆動されるわけで
あるが、第３図ｄの信号の周波数を適当に設定す
ることにより、直流モーター５の慣性力のため
に、駆動電圧が減少する部分であつても直流モー
ター５は大きく速度を減少することなくスムーズ
に回転する。そして、直流モーター５が所定量回
転すると（すなわち、ステージが所定量移動する
と）、ロータリーエンコーダは時刻t4にてフイー
ドバツクパルスを出力する。その結果、偏差カウ
ンタ３の計数値は２となり、Ｄ／Ａ変換器８の出
力信号は、最大値2V0の、のこぎり波状信号に変
化する。従つて、厳密に見れば、時刻t4におい
て、直流モーター５の駆動電圧が急激に変化する
から、ステージ２の動きはぎこちなくなるはずで
あるが、実際には直流モーター５の慣性力のため
に気にならない程度に抑えることができる。そし
て、時刻t5で再び指令パルスが生ずると、偏差カ
ウンタ３の計数値は３となり、Ｄ／Ａ変換器８の
出力信号は、最大値3V0の、のこぎり波状信号と
なる。以下同様に動作し、指令パルスが停止する
と、フイードバツクパルスは入力されるから、偏
差カウンタ３の計数値は３から零まで減算され、
Ｄ／Ａ変換器８の出力信号も最大値3V0の、のこ
ぎり波状信号から、最大値2V0の、のこぎり波状
信号、最大値V0の、のこぎり波状信号と減少し、
それに伴なつて直流モーター１０の速度も低下
し、Ｄ／Ａ変換器８の出力信号が零になると直流
モーター１０は停止する。 Therefore, when a reference pulse as shown in FIG. 2a is output from the reference pulse generation circuit 4, the command pulse generator divides the reference pulse into 1/4 and outputs the reference pulse as shown in FIG. 2b.
It outputs a command pulse like this. As a result, the sawtooth wave generator 7 outputs a sawtooth waveform as shown in FIG. 2c. Therefore, when the command pulse starts to be input to the deviation counter 3 at time t1 , the count value of the deviation counter 3 becomes 1, and correspondingly, the D/A converter 8
The output signal of is modulated by the sawtooth wave of the sawtooth wave generator 7 and has a maximum value V 0 as shown in FIG.
Outputs a sawtooth signal. This signal is transmitted to amplifier 9
The voltage is input to the DC motor 5 as a sawtooth wave-like driving voltage, but the DC motor 5 does not rotate at this level of voltage. Next, when a command pulse is input at time t2 , the count value of the deviation counter 3 becomes 2, and the output signal of the D/A converter 8 becomes a sawtooth waveform signal with a maximum value of 2V 0 (Fig. 2). d). This signal passes through the amplifier 9 and becomes a sawtooth wave driving voltage, but the DC motor 5 does not rotate even with this voltage. When another command pulse is input at time t3 , the count value of deviation counter 3 becomes 3,
The output signal of the D/A converter 8 becomes a sawtooth waveform signal with a maximum value of 3V0 (FIG. 2d). Maximum value 3V 0
becomes a signal sufficient to start rotating the DC motor 5, and the DC motor 5 starts rotating. Although it is driven with a sawtooth wave-like driving voltage, by appropriately setting the frequency of the signal shown in FIG. However, the DC motor 5 rotates smoothly without significantly reducing its speed. Then, when the DC motor 5 rotates by a predetermined amount (that is, when the stage moves by a predetermined amount), the rotary encoder outputs a feedback pulse at time t4 . As a result, the count value of the deviation counter 3 becomes 2, and the output signal of the D/A converter 8 changes to a sawtooth waveform signal with a maximum value of 2V0 . Therefore, if we look at it strictly, the movement of the stage 2 should be awkward because the driving voltage of the DC motor 5 suddenly changes at time t4 , but in reality, the movement of the stage 2 should be awkward due to the inertia of the DC motor 5. It can be suppressed to a level that does not bother you. Then, when a command pulse occurs again at time t5 , the count value of the deviation counter 3 becomes 3, and the output signal of the D/A converter 8 becomes a sawtooth waveform signal with a maximum value of 3V0 . The operation continues in the same manner, and when the command pulse stops, the feedback pulse is input, so the count value of the deviation counter 3 is subtracted from 3 to 0.
The output signal of the D/A converter 8 also decreases from a sawtooth waveform signal with a maximum value of 3V 0 to a sawtooth waveform signal with a maximum value of 2V 0 to a sawtooth waveform signal with a maximum value of V 0 ,
Correspondingly, the speed of the DC motor 10 also decreases, and when the output signal of the D/A converter 8 becomes zero, the DC motor 10 stops.
そして、上述の如き構成であるから、第３図ａ
に示した如く、時刻t4におけるＤ／Ａ変換器８の
出力信号の変化量V1は、従来の回路、すなわち、
第１図においてＤ／Ａ変換器８のゲインをのこぎ
り波状に変化させるのこぎり波発生器７の無い回
路、によつて第２図ａ，ｂ，ｅなる関係のときに
Ｄ／Ａ変換器の出力信号の変化量V0（第３図ｂ）
より十分小さくできるので直流モーター５に与え
る電圧変化が小さくなり、ステージの動きがスム
ーズになることがわかる。 Since the configuration is as described above, Fig. 3a
As shown in FIG .
In Fig. 1, the circuit without the sawtooth wave generator 7 that changes the gain of the D/A converter 8 in a sawtooth waveform produces the output of the D/A converter when the relationships a, b, and e are shown in Fig. 2. Signal variation V 0 (Figure 3b)
It can be seen that since it can be made sufficiently smaller, the voltage change applied to the DC motor 5 becomes smaller, and the movement of the stage becomes smoother.
なお、以上の実施例では、のこぎり波発生器７
として積分回路を用いているので、指令パルスの
周波数が大きくなると、第２図ｄにおいて、１つ
ののこぎり波が零に減ちる前に次ののこぎり波が
立ち上がるので、直流モーター５の駆動電圧の積
分量が増加するから、直流モーター５はそれだけ
高速に回転し、また、指令パルスの周波数が小さ
くなると、第２図ｄにおいて、のこぎり波同志の
間隔が空いてしまうので、直流モーター５の回転
速度は低下する。従つて、いずれの場合にも実際
上支障がない程度にステージ２がスムーズに移動
するように、指令パルスの周波数の範囲及び、の
こぎり波状信号の最大値を実験によつて定めてお
く必要がある。 In addition, in the above embodiment, the sawtooth wave generator 7
As the frequency of the command pulse increases, the next sawtooth wave rises before one sawtooth wave decreases to zero in Figure 2 (d), so the integral of the drive voltage of the DC motor 5 increases. As the amount increases, the DC motor 5 rotates at a higher speed. Also, as the frequency of the command pulse decreases, the spacing between the sawtooth waves increases in Figure 2d, so the rotational speed of the DC motor 5 becomes descend. Therefore, in any case, it is necessary to determine the frequency range of the command pulse and the maximum value of the sawtooth wave signal through experiments so that the stage 2 moves smoothly to the extent that there is no practical problem. .
また、第１図の例を並列的に設けるか、もしく
は交互に制御することによつて、Ｘ方向モーター
とＹ方向モーターとを同様に制御することがで
き、いわゆるＸ−Ｙステージの駆動制御が行なえ
る。 Furthermore, by providing the example shown in Fig. 1 in parallel or controlling them alternately, the X-direction motor and the Y-direction motor can be controlled in the same way, and so-called X-Y stage drive control can be performed. I can do it.
なお、Ｄ／Ａ変換器８のゲインをコントロール
する代わりに増幅器９のゲインをコントロールし
ても良いが、コントロール信号としては、正弦
波、三角波等よりのこぎり波を用いることがステ
ージの動きをよりスムーズにするために好ましい
し、また回路的にも簡単であつて好ましい。 Note that the gain of the amplifier 9 may be controlled instead of controlling the gain of the D/A converter 8, but using a sawtooth wave rather than a sine wave, triangular wave, etc. as the control signal will make the movement of the stage smoother. This is preferable because it makes the circuit more convenient, and it is also preferable because it is simple in terms of circuitry.
さらに第１図の実施例ではロータリーエンコー
ダによつて間接的にステージの移動量を見ている
が、リニアエンコーダ等によりステージの移動量
を直接読み取る如く成しても良いことは明らかで
ある。 Further, in the embodiment shown in FIG. 1, the amount of movement of the stage is indirectly measured using a rotary encoder, but it is obvious that the amount of movement of the stage may be directly read using a linear encoder or the like.
（発明の効果）
以上述べた如く本発明によれば、指令パルスの
１パルスあたりのステージの移動量を小さくする
ことなく、速度変化量を小さくすることができる
ので、安価にスムーズな移動の得られるステージ
の速度制御装置を得ることができる。(Effects of the Invention) As described above, according to the present invention, the amount of speed change can be reduced without reducing the amount of movement of the stage per one pulse of the command pulse, so smooth movement can be achieved at low cost. It is possible to obtain a speed control device for a stage that can be used.
第１図は本発明の一実施例のブロツク図、第２
図は第１図の動作を説明するためのタイムチヤー
ト、第３図は第１図の実施例が従来の例に対して
勝れていることを説明するための説明図、であ
る。
主要部分の符号の説明、１……指令パルス発生
器、２……ステージ、３……偏差カウンタ、５…
…直流モーター、６……ロータリーエンコーダ、
７……のこぎり波発生器、８……Ｄ／Ａ変換器、
９……増幅器。
FIG. 1 is a block diagram of one embodiment of the present invention, and FIG.
The figure is a time chart for explaining the operation of FIG. 1, and FIG. 3 is an explanatory diagram for explaining that the embodiment of FIG. 1 is superior to the conventional example. Explanation of symbols of main parts, 1... Command pulse generator, 2... Stage, 3... Deviation counter, 5...
...DC motor, 6...Rotary encoder,
7... Sawtooth wave generator, 8... D/A converter,
9...Amplifier.
Claims (1)
イードバツクパルスを出力するエンコーダ手段
と、前記ステージの移動量に対応した指令パルス
を出力する指令パルス発生器と、前記フイードバ
ツクパルスと前記指令パルスの差に応じた速度で
前記ステージを駆動するための直流モーターを含
む駆動手段と、を有するステージの速度制御装置
において、 前記指令パルスよりも小さな周期ののこぎり波
状に前記直流モーターの駆動電圧を変化せしめる
ゲインコントロール手段を前記駆動手段に設けた
ことを特徴とするステージの速度制御装置。[Scope of Claims] 1. A stage, an encoder means for outputting a feedback pulse every predetermined amount of movement of the stage, a command pulse generator for outputting a command pulse corresponding to the amount of movement of the stage, and a command pulse generator for outputting a command pulse corresponding to the amount of movement of the stage. A stage speed control device comprising: a drive means including a DC motor for driving the stage at a speed corresponding to a difference between an yield back pulse and the command pulse, 1. A stage speed control device, characterized in that said drive means is provided with gain control means for changing the drive voltage of a DC motor.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58226344A JPS60118914A (en) | 1983-11-30 | 1983-11-30 | Speed controller of stage |
| US06/675,323 US4577141A (en) | 1983-11-30 | 1984-11-27 | System for driving a movable stage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58226344A JPS60118914A (en) | 1983-11-30 | 1983-11-30 | Speed controller of stage |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60118914A JPS60118914A (en) | 1985-06-26 |
| JPH0477324B2 true JPH0477324B2 (en) | 1992-12-08 |
Family
ID=16843694
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58226344A Granted JPS60118914A (en) | 1983-11-30 | 1983-11-30 | Speed controller of stage |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60118914A (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57144112U (en) * | 1981-03-02 | 1982-09-10 |
-
1983
- 1983-11-30 JP JP58226344A patent/JPS60118914A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60118914A (en) | 1985-06-26 |
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