JPS6149681B2 - - Google Patents
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- Publication number
- JPS6149681B2 JPS6149681B2 JP1384379A JP1384379A JPS6149681B2 JP S6149681 B2 JPS6149681 B2 JP S6149681B2 JP 1384379 A JP1384379 A JP 1384379A JP 1384379 A JP1384379 A JP 1384379A JP S6149681 B2 JPS6149681 B2 JP S6149681B2
- Authority
- JP
- Japan
- Prior art keywords
- low
- pass filter
- servo
- motor
- circuit
- 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
Links
- 238000013500 data storage Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 239000013585 weight reducing agent Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012886 linear function Methods 0.000 description 1
Landscapes
- Moving Of The Head To Find And Align With The Track (AREA)
- Feedback Control In General (AREA)
- Control Of Position Or Direction (AREA)
Description
【発明の詳細な説明】
本発明はサーボ回路の制御装置に関し、さらに
詳しくは低域をもち上げるように改善した位置積
分方式によるサーボ回路の制御装置に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a servo circuit, and more particularly to a control device for a servo circuit using a position integral method improved to raise the low frequency range.
一般にリニアモータにより駆動されデータの貯
蔵媒体の任意の位置にヘツドの位置決めを行なう
キヤリツジの軽量化を考えた場合、キヤリツジの
機構に基づく共振特性の向上を望むことはできな
いためにキヤリツジを制御するサーボ回路の帯域
は限定されてしまう。そこでサーボ回路の帯域を
一定とするとキヤリツジの質量とサーボ回路のス
テイフネスは比例する。ところで摩擦力や外力は
キヤリツジの軽量化に比例して減少することは望
めない。したがつてキヤリツジの軽量化によつて
サーボ系のステイフネスが下り摩擦力や外力の影
響が無視できなくなる。 Generally, when considering the weight reduction of a carriage that is driven by a linear motor and positions the head at an arbitrary position on the data storage medium, it is not possible to improve the resonance characteristics based on the mechanism of the carriage. The band of the circuit is limited. Therefore, if the band of the servo circuit is constant, the mass of the carriage and the stiffness of the servo circuit are proportional. However, it cannot be expected that frictional force and external force will decrease in proportion to the weight reduction of the carriage. Therefore, as the weight of the carriage is reduced, the stiffness of the servo system decreases, and the effects of frictional force and external force cannot be ignored.
そこでこの摩擦対策としてサーボ系のステイフ
ネス（復原力と位置偏差の比）を大きく出来る位
置積分方式すなわち低域持ち上げ方式が用いられ
ている。この方式によるサーボ系を第１図に示
す。 Therefore, as a countermeasure against this friction, a position integral method, that is, a low-frequency lifting method, is used, which can increase the stiffness (ratio of restoring force to positional deviation) of the servo system. A servo system based on this method is shown in FIG.
尚、以下の説明において、１次遅れ要素は、サ
ーボの固有振動周波数に対し、Ａ／（TS＋１）
の形式の１次遅れをＴが十分大きいように選ぶこ
とにより積分器の働きをする。また、磁気デイス
ク装置等のサーボ系においては、位置信号は目的
（所望）位置信号（第１図において、リニアモー
タ１の出力である変位Ｘに加算して与えられる）
と実位器信号の差で与えられる。 In the following explanation, the first-order delay element is A/(TS+1) with respect to the natural vibration frequency of the servo.
By selecting a first-order delay of the form such that T is sufficiently large, it functions as an integrator. In addition, in a servo system such as a magnetic disk device, the position signal is a target (desired) position signal (in Fig. 1, it is given by adding it to the displacement X that is the output of the linear motor 1).
It is given by the difference between and the real position device signal.
従つて第１図に示すサーボ系において、Ｘ＝０
となるように制御することにより、所望位置に位
置決めされたことになる。 Therefore, in the servo system shown in Figure 1, X=0
By controlling it so that it becomes, it is possible to position it at the desired position.
第１図において１はリニアモータ、２はパワー
増幅器、３は第２の低域濾波器（電流積分器）、
４は位置偏差検出回路、５は第１の低域濾波器
（位置積分器）である。 In Fig. 1, 1 is a linear motor, 2 is a power amplifier, 3 is a second low-pass filter (current integrator),
4 is a position deviation detection circuit, and 5 is a first low-pass filter (position integrator).
つぎにこれらの回路素子の入出力関係を示すと
つぎのごとくになる。 Next, the input/output relationships of these circuit elements are as follows.
(イ) リニアモータ
Ｘ＝Ｂｌ・Ｉ／ｍＳ２ (1)
（Bl：モータトルク定数、Ｉ：モータ電流、
ｍ：モータ可動部質量、Ｘ：変位）
(ロ) パワー増幅器（定電流回路）
Ｉ＝Ｅ／β（βは電流電圧変換係数） (2)
(ハ) 第２の低域濾波器
Ｅc＝Ｃｖ／ＴｃＳ＋１Ｉ (3)
（Ｃv、Ｔcは定数）
(ニ) 位置偏差検出回路
Ｅp1＝KX（Ｋは定数） (4)
(ホ) 第１の低域濾波器
Ｅp2＝Ｇ／Ｔ２Ｓ＋１Ｅp1 (5)
（Ｇ、T2は定数）
第１図のごときサーボ系は第１の低域濾波器５
によつて低域特性を改善したものであるが、この
方式においては第２の低域濾波器３および第１の
低域濾波器５の初期値の設定が重要であり、この
値が適当でないとセツトリングタイムの増加をも
たらす。(B) Linear motor X=Bl・I/mS 2 (1) (Bl: Motor torque constant, I: Motor current,
m: mass of motor moving part, X: displacement) (b) Power amplifier (constant current circuit) I = E/β (β is current-voltage conversion coefficient) (2) (c) Second low-pass filter E c = C v /T c S+1I (3) (C v and T c are constants) (d) Position deviation detection circuit E p1 = KX (K is a constant) (4) (e) First low-pass filter E p2 = G/T 2 S+1E p1 (5) (G, T 2 are constants) The servo system as shown in Figure 1 is the first low-pass filter 5.
However, in this method, it is important to set the initial values of the second low-pass filter 3 and the first low-pass filter 5, and this value may not be appropriate. This results in an increase in settling time.
本発明の目的はこの第１および第２の低域濾波
器の初期値を設定する装置を提供することにあ
る。 An object of the present invention is to provide a device for setting initial values of the first and second low-pass filters.
本発明によればデータを貯蔵する媒体にデータ
の読み書きを行うために位置決めされるキヤリツ
ジを駆動するモータと、前記キヤリツジの位置偏
差を検出する位置偏差検出器と、該位置偏差検出
器の出力を積分し低域をもち上げるための第１の
低域濾波器と、前記モータの入力電流を積分する
ための第２の低域濾波器と、前記第２の低域濾波
器の出力、前記位置偏差検出器の出力および前記
第１の低域濾波器の出力を加算して前記モータに
供給する増幅器よりなるサーボ回路において、サ
ーボ突入時に前記第１の低域濾波器および前記第
２の低域濾波器の初期値を前記サーボ回路のサー
ボ系の特性根のうち減衰のわるい２個の実根の応
答が零となる値に設定する初期値設定回路を設け
たことを特徴とするサーボ回路の制御装置が提案
される。 According to the present invention, there is provided a motor for driving a carriage positioned to read and write data on a data storage medium, a position deviation detector for detecting a position deviation of the carriage, and an output of the position deviation detector. a first low-pass filter for integrating and raising low frequencies; a second low-pass filter for integrating the input current of the motor; the output of the second low-pass filter; and the position of the second low-pass filter. In a servo circuit comprising an amplifier that adds an output of a deviation detector and an output of the first low-pass filter and supplies the sum to the motor, the output of the first low-pass filter and the second low-pass filter is added when the servo enters. Control of a servo circuit, characterized in that an initial value setting circuit is provided for setting the initial value of the filter to a value such that the response of two real roots with poor attenuation among the characteristic roots of the servo system of the servo circuit is zero. A device is proposed.
以下本発明にかかるサーボ回路の制御装置の実
施例について第１図以下を参照しつつ詳細に説明
する。 Embodiments of the servo circuit control device according to the present invention will be described in detail below with reference to FIG. 1 and subsequent figures.
まず第１図のサーボ系においてサーボ突入時の
リニアモータ１の変位の初期値をx0、その速度の
初期値をｘ〓０、電圧Ｅcの初期値をＥc0、電圧Ｅp2
の初期値をＥp20とすれば変位Ｘは下記のごとく
なる。 First, in the servo system shown in Fig. 1, the initial value of the displacement of the linear motor 1 at the time of servo entry is x 0 , the initial value of its speed is x〓 0 , the initial value of the voltage E c is E c0 , and the voltage E p2
If the initial value of is E p20 , the displacement X is as follows.
Ｘ＝（Ｔ２Ｓ＋１）（ＴｃＳ＋Ｄ１）（Ｓ・ｘ０＋ｘ０）−｛Ｚｐ（ＴｃＳ＋１）Ｚｃ（Ｔ２Ｓ＋１）｝／ＴｃＴ２
・Ｓ４＋（Ｔｃ＋Ｄ１・Ｔ２）Ｓ３＋（Ｄ１＋Ｄ２・Ｔ１・Ｔｃ）Ｓ２＋Ｄ２（Ｔ１＋Ｔｃ）Ｓ＋Ｄ２……(1)
但し(1)式において、
D1＝１＋Ｃv／β、
D2＝（Bl／ｍ）（Ｋ／β）（１＋Ｇ）、
T1＝T2／（１＋Ｇ）、
Ｚp＝（Bl／ｍ）（Ｅp20／β）T2、
Ｚc＝（Bl／ｍ）（Ｅc0／β）Ｔc
とした。尚、第(1)式の導出は、第１図に示される
ブロツク図の夫々をラプラス変換することにより
求められる。X=( T2S +1)( TcS + D1 )(S・x0 + x0 )-{ Zp ( TcS +1) Zc ( T2S + 1)}/ TcT2
・S 4 + (T c + D 1 · T 2 ) S 3 + (D 1 + D 2 · T 1 · T c ) S 2 + D 2 (T 1 + T c ) S + D 2 ... (1) However, formula (1) In, D 1 = 1+C v /β, D 2 = (Bl/m) (K/β) (1+G), T 1 = T 2 /(1+G), Z p = (Bl/m) (E p20 /β ) T 2 , Z c = (Bl/m) (E c0 /β) T c . Incidentally, equation (1) is derived by performing Laplace transform on each of the block diagrams shown in FIG.
例えば、ミクシンスキー著の「演算子法」（裳
華房より昭和38年12月１日に第１版発行、高橋安
針訳）等により記述されている。 For example, it is described in "Operator Method" by Mikusinski (first edition published by Shokabo on December 1, 1960, translated by Yasuharu Takahashi).
ところでこのサーボ系の特性根は１対の複素根
と２個の実根となるが、この実根のうちの一方は
位置積分に起因するものでＳ≒−1.0／T1となり
（この根をS0とする）、他の実根は第１の低域濾波
器５を外したときのサーボループに起因するもの
で（この根をS1とする）、共に減衰のよくない根
である。 By the way, the characteristic roots of this servo system are a pair of complex roots and two real roots, and one of these real roots is due to the position integral and becomes S≒-1.0/T 1 (this root can be expressed as S 0 ), and the other real root is due to the servo loop when the first low-pass filter 5 is removed (this root is S 1 ), and both are roots with poor attenuation.
そこでＳ＝S0のとき分子が零となる条件をとる
と、
（T2・S0＋１）（Ｔc・S0＋D1）（S0・x0
＋ｘ〓０）−｛Ｚp（ＴcS0＋１）＋Ｚc（T2S0
＋１）｝＝０ ………(2)
またＳ＝S1のとき分子が零となる条件をとる
と、
（T2・S1＋１）（Ｔc・S1＋D1）（S1・x0
＋ｘ〓０）−｛Ｚp（Ｔc・S1＋１）＋Ｚc（T2S1
＋１）｝＝０ ………(3)
となる。上記(2)、(3)式を連立させてＺp、Ｚcを定
めると
Ｚp＝−（Ｔ２Ｓ１＋１）（Ｔ２Ｓ０＋１）｛〔Ｔｃ（Ｓ０＋Ｓ１）＋Ｄ１〕ｘ０＋Ｔｃｘ０｝／Ｔ２−Ｔｃ………(
4)
Ｚc＝（ＴcS0＋D1）（S0x0＋ｘ〓０）
＋（ＴｃＳ０＋１）（Ｔ２Ｓ１＋１）｛〔Ｔｃ（Ｓ０＋Ｓ１）＋Ｄ１〕ｘ０＋Ｔｃｘ０｝／Ｔ２−Ｔｃ ………(5)
ところで上記第(4)式および第(5)式のＺpおよび
ＺcはすでにのべたようにＥp20およびＥc0にそれ
ぞれ比例することから上記(4)式および(5)式により
あたえられた初期条件x0、ｘ〓０に対する最適のＥ
p20およびＥc0が求められる。 Therefore, if we take the condition that the molecule is zero when S=S 0 , we get (T 2・S 0 + 1) (T c・S 0 + D 1 ) (S 0・x 0 + x〓 0 ) − {Z p (T c S 0 +1) + Z c (T 2 S 0 +1)} = 0 (2) Also, if we take the condition that the numerator is zero when S = S 1 , then (T 2・S 1 +1) (T c・S 1 +D 1 )(S 1・x 0 +x〓 0 )−{Z p (T c・S 1 +1)+Z c (T 2 S 1 +1)}=0 (3). When Z p and Z c are determined by simultaneous equations (2) and (3) above, Z p =-(T 2 S 1 +1) (T 2 S 0 +1) {[T c (S 0 + S 1 ) + D 1 ] x 0 + T c x 0 }/T 2 - T c ………(
4) Z c = (T c S 0 + D 1 ) (S 0 x 0 + x〓 0 ) + (T c S 0 +1) (T 2 S 1 +1) {[T c (S 0 + S 1 ) + D 1 ] x 0 +T c x 0 }/T 2 -T c ......(5) By the way, Z p and Z c in the above equations (4) and (5) can be expressed as E p20 and E c0 as already stated. Since they are proportional to each other, the optimal E for the initial conditions x 0 and x〓 0 given by the above equations (4) and (5) is
p20 and E c0 are determined.
ところでこれらＥp20およびＥc0はそれぞれ第２
図ＡおよびＢのごとく直線関数となり、かかる直
線は演算増幅器により簡単に作ることができる。
また位置決め誤差の要求が厳しくないときはＺp
＝０として前記(3)式のみからＥc0を定めてもよ
い。 By the way, these E p20 and E c0 are the second
It becomes a linear function as shown in Figures A and B, and such a straight line can be easily created using an operational amplifier.
Also, when the positioning error requirements are not strict, Z p
= 0 and E c0 may be determined only from the above equation (3).
第３図に本発明にかかるサーボ回路における制
御回路の構成を示す。第３図において、１１はＥ
c0の設定回路であつて、演算増幅器１１ａ、抵抗
R1，R2，R3およびR4を含んで構成され、且つＥv
はリニアモータの可動部の速度ｘ〓を示す信号でＥ
v＝Ｋvｘ〓（Ｋvは比例定数Ｖ／ｍ／Ｓで示される
信号としＥIはリニアモータに流れる電流を表わ
す信号としＥI＝ＫcＩ（Ｋcは比例常数Ｖ／Ａ）
とする。）３は第２の低域濾波器であつて第１図
におけるそれに対応する。また１２はＥp20の設
定回路であつて、演算増幅器１２ａ、抵抗R14，
R15，R16，R17を含んで構成され、すでにのべた
信号ＥvおよびＥp1が入力される。スイツチSW1
およびSW2はアナログスイツチでサーボ突入直前
までオン状態にありサーボ突入後はオフされるス
イツチである。 FIG. 3 shows the configuration of a control circuit in a servo circuit according to the present invention. In Figure 3, 11 is E
c0 setting circuit, operational amplifier 11a, resistor
Comprised of R 1 , R 2 , R 3 and R 4 , and E v
is a signal indicating the speed x of the moving part of the linear motor, and E
v = K v x〓 (K v is a signal expressed by the proportional constant V/m/S, and E I is a signal representing the current flowing through the linear motor. E I = K c I (K c is the proportional constant V/A)
shall be. )3 is a second low-pass filter and corresponds to that in FIG. 12 is a setting circuit for E p20 , which includes an operational amplifier 12a, a resistor R 14 ,
It is configured to include R 15 , R 16 , and R 17 , and the signals E v and E p1 mentioned above are input thereto. Switch SW 1
SW 2 is an analog switch that remains on until just before the servo enters, and is turned off after the servo enters.
第３図のごとく構成された回路においてＥc0設
定回路はサーボ突入直前まではスイツチSW1によ
り第２の低域濾波器３に接続されておつて、キヤ
パシタC1に初期値Ｅc0に対応する電圧を充電しサ
ーボ突入後はスイツチSW1は開放される。Ｅp20
設定回路１２はサーボ突入直前まではスイツチ
SW2により第１の低域濾波器５に接続されておつ
てキヤパシタC2に初期値Ｅp20に対応した電圧を
充電し、サーボ突入後はスイツチSW2は開放され
る。 In the circuit configured as shown in Fig. 3, the E c0 setting circuit is connected to the second low-pass filter 3 by switch SW 1 until just before the servo enters, and the capacitor C 1 corresponds to the initial value E c0 . After charging the voltage and entering the servo, switch SW 1 is opened. E p20
The setting circuit 12 is a switch until just before servo entry.
SW 2 connects to the first low-pass filter 5 and charges the capacitor C 2 with a voltage corresponding to the initial value E p20 , and after the servo enters, the switch SW 2 is opened.
以上詳細に説明したごとく、本発明は低域を持
ち上げる位置積分方式を用いたサーボ回路におい
てサーボ突入の条件に応じてサーボ系の減衰の悪
い特性根の応答を零にするように積分器の初期値
を設定したものであつてサーボ系のセツトリング
タイムを減少する効果が大である。 As explained in detail above, the present invention is designed to adjust the initial stage of the integrator so that the response of the poorly damped characteristic root of the servo system is reduced to zero according to the servo entry conditions in a servo circuit using a positional integration method that lifts the low frequency range. This is a set value and is very effective in reducing the settling time of the servo system.
第１図は従来のサーボ回路のブロツク図、第２
図は第１図のブロツク図における電流積分器およ
び位置積分器の最適初期値の初期条件に対する変
化を示す図表、第３図は本発明にかかるサーボ回
路の制御回路を示す。
図において、１１が第２の低域濾波器の初期値
設定回路、１２が第１の低域濾波器の初期値設定
回路、SW1およびSW2はサーボ突入までオン状態
にありサーボ突入後オフされるスイツチである。
Figure 1 is a block diagram of a conventional servo circuit, Figure 2 is a block diagram of a conventional servo circuit.
This figure is a chart showing changes in the optimum initial values of the current integrator and position integrator in the block diagram of FIG. 1 with respect to the initial conditions, and FIG. 3 shows a control circuit for a servo circuit according to the present invention. In the figure, 11 is the initial value setting circuit for the second low-pass filter, 12 is the initial value setting circuit for the first low-pass filter, SW 1 and SW 2 are in the on state until the servo enters, and are turned off after the servo enters. This is the switch that will be used.
Claims (1)
行うために位置決めされるキヤリツジを駆動する
モータと、前記キヤリツジの位置偏差を検出する
位置偏差検出器と、該位置偏差検出器の出力を積
分し低域をもち上げるための第１の低域濾波器
と、前記モータの入力電流を積分するための第２
の低域濾波器と、前記第２の低域濾波器の出力、
前記位置偏差検出器の出力および前記第１の低域
濾波器の出力を加算して前記モータに供給する増
幅器よりなるサーボ回路において、サーボ突入時
に前記第１の低域濾波器および前記第２の低域濾
波器の初期値を前記サーボ回路のサーボ系の特性
根のうち減衰のわるい２個の実根の応答が零とな
る値に設定する初期値設定回路を設けたことを特
徴とするサーボ回路の制御装置。1. A motor that drives a carriage that is positioned to read and write data on a data storage medium, a position deviation detector that detects the position deviation of the carriage, and a low frequency detector that integrates the output of the position deviation detector. a first low-pass filter for raising the input current of the motor; and a second low-pass filter for integrating the input current of the motor.
a low pass filter, and an output of the second low pass filter,
In a servo circuit including an amplifier that adds the output of the position deviation detector and the output of the first low-pass filter and supplies the sum to the motor, the first low-pass filter and the second low-pass filter are added together when the servo enters. A servo circuit characterized in that an initial value setting circuit is provided for setting the initial value of the low-pass filter to a value such that the response of two real roots with poor attenuation among the characteristic roots of the servo system of the servo circuit is zero. control device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1384379A JPS55108008A (en) | 1979-02-10 | 1979-02-10 | Initial value set system for servo circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1384379A JPS55108008A (en) | 1979-02-10 | 1979-02-10 | Initial value set system for servo circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55108008A JPS55108008A (en) | 1980-08-19 |
| JPS6149681B2 true JPS6149681B2 (en) | 1986-10-30 |
Family
ID=11844549
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1384379A Granted JPS55108008A (en) | 1979-02-10 | 1979-02-10 | Initial value set system for servo circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS55108008A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0661372U (en) * | 1993-01-28 | 1994-08-30 | 新日本製鐵株式会社 | Gas shield arc welding nozzle and tip |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61121110A (en) * | 1984-11-19 | 1986-06-09 | Fujitsu Ltd | Servo controller |
| JP2007145366A (en) * | 2005-11-29 | 2007-06-14 | Ishida Co Ltd | Bag forming and packaging machine |
-
1979
- 1979-02-10 JP JP1384379A patent/JPS55108008A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0661372U (en) * | 1993-01-28 | 1994-08-30 | 新日本製鐵株式会社 | Gas shield arc welding nozzle and tip |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55108008A (en) | 1980-08-19 |
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