Operator s Panel. Graphical User Interface (GUI) CNC System. Architecture of CNC Unit. Interpolator. Control Panel. Indirect Control.

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1 Outline CC C Sytem Computer umerial Control CC Sytem Control Panel Control Sytem Diret Control Indiret Control Arhiteture o CC Unit Control Algorithm Interpolator Linear Cirular Courtey o Heidenhain Corp. CC i a multi-proeor ontrol ytem deigned to perorm the tak ommonly enountoured in metal working mahinery and other mahine tool: Motion ontrol / Servo ontrol Multi-axi motion ontrol Spindle motion ontrol Peripheral unit ontrol / PLC Tool hanger / turret Coolant / lubriant ontrol Tool alignment / other auxillary untion Command generation Interpolation / ommand haping Mahine tool yle Tool oet ompenation Paive error ompenation Diagnoti and alibration Uer Interaing Program editing / torage / imulation File management Tool management Manual data input (MDI Mahine / human interaing Chapter 9 ME 440 Chapter 9 ME Operator Panel Graphial Uer Interae (GUI Courtey o Fanu Ltd. CC Control Panel inlude all relevant peripheral devie to operate a mahine tool: Diplay (LCD Keyboard LED indiator Swithe Puh-button Knob GUI widely vary rom one manuaturer to another. GUI diplay important inormation about the CC mahine tool: Tool Coordinate Feedrate, Spindle peed (and Power Tool and WCS Seleted CC Mahine Mode Content o Relevant CC regiter C Code being exeuted Tool path And more... Chapter 9 ME Chapter 9 ME 440 5

2 FAUC i Serie Diplay FAUC i Serie (Cont d Chapter 9 ME Advaned anned yle or milling: Drilling / Hole pattern Faing / Side utting Poketing Contour mahining Mahining imulation: Tool path drawing Animated drawing on a olid model Rotation o a produt Chapter 9 ME Emergeny Stop Button When the emergeny top button i preed, the mahine tool i topped intantaneouly: CC i reet, Spindle and all axe are topped, Other ation are interrupted. CC alarm i iued. (Depreed emergeny button i releaed when rotated in the hown diretion: A old tart i uually needed to reume the mahining operation. Feedrate Override Override Seletor Spindle Override Operator an manually override the programmed eedrate (F ode a well a the pindle peed (a iued by S ode. Enable the optimization o the mahining operation experimentally! Feedrate override uually range between 0 to 10% (00% i alo ommon! o the programmed rate. Spindle override generally range between 50 to 10% o the programmed peed. Chapter 9 ME Chapter 9 ME 440 9

3 Main CC Mode Seletion Continuou Jog Mode Main Mode Seletor Auto Mode (Memory Mode allow the automati exeution o a part program being eleted rom program ile in CC diretory. Edit Mode enable entering and editing o part program tored in CC diretory. In Manual Data Input (MDI Mode, operator an reate and exeute a program oniting up to 10 line rom the MDI panel. Generally, ingle blok o C ode i entered and exeuted or teting purpoe. In Remote Mode (alo alled DC mode, it i poible to perorm mahining while a program i being read in rom a remote buer. Continuou Jog Mode Seletor LED Indiator Axi Sele etion Key y Jog Diretion Key Jog mode allow the operator to move the tool manually along a eleted axi via peial button on the panel: Very ueul when etting up a workpiee. In ontinuou jog mode, the tool move ontinuouly at a ontant peed a long a a jog diretion key i preed. Correponding LED indiator over the eleted axi (key light up. Chapter 9 ME Chapter 9 ME Axi Seletio on Key Inremental Jog Mode Seletor Inrement Seletion Key Inremental Jog Mode In inremental jog mode, a oon a a jog diretion key (+ or i preed (and releaed!; the tool move to a predetermined ditane along the eleted axi. Travel ditane i hoen by Inrement Seletion key (a.k.a. multiplier : X1: 1 BLU (0.001 mm X10: 10 BLU (0.01 mm X100: 100 BLU (0.1 mm X1000: 1000 BLU (1 mm Jog Diretion Key Chapter 9 ME Handle Mode Seletor Inrement Seletion Key Handle Jog Mode In Handle jog mode, the tool move to a predetermined travel ditane inrementally along the eleted axi a the handle (a.k.a. manual pule generator MPG i rotated. Travel ditane i again hoen by Inrement Seletion key. Mot CC mahine tool are equipped with portable MPG pendant o that the operator ould examine the workpae loely in thi jog mode. Chapter 9 ME

4 Indiret Control Sytem Control Sytem Generi CC Sytem Cutting Fore tool loation C Program eed Interpolator C Program tool eed loation CC Sytem Poition ommand Motion Controller Diret Control Sytem Interpolator CC Sytem Poition ommand P Motion Controller Torque ommand Motor Drive Angular poition eedbak Torque ommand Motor Drive Poition i enor Servo motor Servo motor Diret poition eedbak Table Ball Srew Shat Table Ball Srew Shat Part ut Part ut Poition enor x ( + e( Control m( m(t ( Drive + τ (t x(t m Interpolator Feed Drive _ Algorithm Motor Torque Motor ommand torque (voltage C Program CC Sytem Poition ommand x( Clok Synhronization Signal T ut ae Outpu Intera Senor nterae S In Poition Senor Carriage' poition In thi diret ontrol ytem, the poition o the arriage (x i meaured and ampled by thi impliied CC ytem. The interpolator ompute the deired poition (o (x the arriage at a partiular intant in time uing the C program. Chapter 9 ME Chapter 9 ME Generi Control Sytem (Cont d The ontrol algorithm irt determine the deviation (e = x-x o the eed-drive ytem rom the deired path and then alulate the orretive ation (m. The orretion ignal (alled manipulation i ent to the output interae generating a orreponding voltage m(t. Thi voltage erve a a torque ommand or the motor drive whih in turn ontrol the ervo-motor to produe the deired d torque. Hene, the generated torque (τ m ompenate the diturbane on the eed-drive d ytem and put the arriage bak to it deired oure. Computer Control Eah phyial quantity (uh a poition meaurement, error, et. in CC ytem (a.k.a. ontrol omputer i repreented by a orreponding binary number with a inite length: Byte / word Integer, long integer Floating point number et. All omputation and I/O operation are ynhronized by a mater lok. Chapter 9 ME Chapter 9 ME

5 Computer Control (Cont d Inide the omputer, eah quantity i valid at only direte-time interval: t = {0, T, T, 3T,..., kt,...} T i alled ampling period o the omputer. In direte-time domain, the time dependene among variou quantitie o interet are repreented by a time index: x(t=kt = x(kt = x( where k = 0, 1,,... Integer k i alled time index. Control Algorithm Control algorithm an be expreed in term o a inite dierene equation. That i, it i an algebrai expreion whih depend on not only the hitory o the input but alo that o the output: I ( k = a im ( k i + b je ( k m j i= 1 j= 0 a i,b j are the ontant oeiient o the equation; m( urrent value o the output t = kt; m(k-1 i old value o t = (k-1t,... ; e( urrent value o the input t = kt; e(k-1 i old value o t = (k-1t,... ; J Chapter 9 ME Chapter 9 ME Control Algorithm (Cont d Control Algorithm (Cont d 1. Read x ( rom the interpolator.. Read the poition meaurement x(. ( 3. Calulate the error: e( = x ( - x(. 4. Compute the orretion ignal: m(= -a 1 m(k-1 a m(k b 0 e( + b 1 e(k Send m( to the output interae. 6. Wait till the end o the period T. 7. Go to Step 1. Read the mea auremen nt alulat te the retion igna al C orr n orretio al Outp put the igna Wa ait till the end o perio od, T Read the mea auremen nt Time Chapter 9 ME Chapter 9 ME 440 1

6 Interpolator Interpolator i an advaned ommand generation algorithm exeuted by the CC ytem. By interpreting the ode in the deault C program, the interpolator t generate the ollowing ommand: The deired poition and veloity o eah axi The deired veloity o pindle (and angular poition wherever neeary The appropriate peripheral unit ommand: Coolant on / o Spindle on / o Tool hange The ommand aoiated with the (anned mahine yle. Interpolator (Cont d Sine the ommand are to be ed to the axi-poition ontrol (a.k.a. ervo yle at eah ampling period T, ertain time retrition are impoed on the interpolation algorithm. Furthermore, the interpolator ha to arry out ompliated trigonometri alulation involved in the tool radiu ompenation. Chapter 9 ME 440 Chapter 9 ME Interpolation Type Three type o interpolation are ommonly utilized in CC tehnology: Retilinear / Linear Cirular Helial More advaned interpolation type are alo ued in modern CC mahine tool: Paraboli URBS Chapter 9 ME Y y y Linear Interpolation G90 G1 Xx Yy Zz F Let u irt alulate travel time between thee point: T t = ( x x + ( y y ( / 60 + ( z z Hene, number o ommand to be generated X x x through out thi motion Z beome z T Tt = int T z x x X Here, int { } round it argument to the nearet integer while T denote the ampling time. Chapter 9 ME 440 5

7 Linear Interpolation (Cont d The interpolation equation take the ollowing orm: x ( = x ( k 1 + Δx y ( = y ( k 1 + Δy z ( = z ( k 1 + Δz In thee equation, k = 1,,..., ; x(0 = x ; y(0 = y ; z(0 = z The ontant an be expreed a x x y y Δ x = ; Δy = ; z z Δz = Chapter 9 ME Y Y' O (x,y (x',y' Cirular Interpolation G90 G17 G3 Xx Yy Rr F r k (k+1,y'(k+1 (,y'( (x',y' ( x x + ( y y = r ( x x + ( y y = r Solving thee equation give the oordinate o the enter (x,y. X' X The poition at t = kt an be expreed a = r o( kδθ y'( = r in( kδθ The poition at t = (k+1t beome x' ( k + 1 = r o(( k + 1 Δθ y' ( k + 1 = r in(( k + 1 Δθ Chapter 9 ME Cirular Interpolation (Cont d Expanding thee term yield y'( k + 1 = r o( kδθ o( Δθ r in( kδθ in( Δθ y '( k + 1 = r 1443 in( k Δ θ o( Δ θ + r 1443 o( k Δ θ in( Δ θ y'( When thee equation are hited bakward in time (k k-1, we get = o( Δθ k 1 in( Δθ y'( k 1 y'( = o( Δθ y'( k 1 + in( Δθ k 1 with x (0 = x x and y (0 = y y. Cirular Interpolation (Cont d ote that θ θ Δθ = r ( θ θ int T 60 = 1 x x 1 x x θ = o θ = o r r Thu, we have x ( = + x ; y ( = y'( + y Chapter 9 ME Chapter 9 ME 440 9

8 50 10 Y [mm] D A Sample to be generated v = 600 [mm/min] Example C B G90 (ABSOLUTE COORDIATES G01 X0 Y0 Z0 F600 (PT 0 X0 Y10 (PT A X60 (PT B Y50 (PT C X0 (PT D Y10 (PT A X0 Y0 Z0 (GO TO PT 0 M30 X [mm] X, Y, Z: Detination Coordinate F: Feedrate (veloity in mm/min G90: Abolute Coordinate Speiied G01: Linear Interpolation Mode Chapter 9 ME