CLS Data Interpolation with Spline Curves and Its Post Processing for Generating a Robot Language

Size: px

Start display at page:

Download "CLS Data Interpolation with Spline Curves and Its Post Processing for Generating a Robot Language"

Archibald Hudson
5 years ago
Views:

1 Proceedngs of the 5th IIAE Internatonal Conference on Industral Applcaton Engneerng 07 CLS Data Interpolaton wth Splne Curves and Its Post Processng for Generatng a Robot Language Fusaom Nagata a,*, Yuda Okada a, akamasa Kusano b, Kego Watanabe c a Department of Mechancal Engneerng, Faculty of Engneerng, okyo Unversty of Scence, Yamaguch Sanyo-Onoda , Japan b SOLIC Co., Ltd. Omuta, , Japan c Graduate School of Natural Scence and echnology, Okayama Unversty Okayama , Japan *Correspondng Author: nagata@rs.tusy.ac.jp Abstract In ths paper, an nterpolaton method wth splne curves s proposed to smooth cutter locaton source data called CLS data. rd -order and 5 th -order splne curves are easly mplemented for nterpolaton. hen, a post processor s desgned for an ndustral robot FANUC R000C to produce FANUC robotc program called LS format. he post processor works as a straghtforward and cooperatve nterface between CAD/CAM systems and the ndustral robot, so that a desrable teachng-less operaton envronment s realzed. he valdty and usefulness of the proposed methods are evaluated through a smulaton on FANUC RoboGude and an actual machnng eperment wth the robot. he FANUC RoboGude s a robotc smulaton envronment that can eecute both the robot s moton and applcaton, largely reducng the setup tme and rsk n usng an actual robot. Keywords: Industral robot, nterpolaton, splne curve, CAD/CAM, CLS data, eachng less, FANUC robotc program, LS format, Machnng robot.. Introducton Up to now, a lot of researches and efforts have been dedcated to develop user-frendly data nterface for ndustral robots. For eample, Xuejuan et al. presented a novel robot sculpturng plannng method for the D sculpturng wth CAD-geometry data. An automatc trajectory generaton from the D CAD models of freeform surfaces to the machnng tool path by the lnear nterpolaton was descrbed []. Solvang et al. consdered a robotc CAM for machnng operatons usng an ndustral robot. he system coped wth the new machnng standard codes called SEP-NC [], whch s a machne tool control language ncludng geometrc dmenson and tolerance data for nspecton. Also, many off-lne programmng methods have been proposed to reduce the load of robot programmng. However, some practcal ssues such as cable/hose tanglng, robot confguraton, collson and reachablty have not been well overcome yet. Chen and Sheng dscussed a new method to generate robot programs whle dealng wth those problems []. he authors presented a machnng system based on an ndustral robot RVA for foamed polystyrene materals [4]. he drect servo system developed for the robot could deal wth NC and CLS fles as desred trajectores, so that a useful nterface wthout usng a robot language between operators and the machnng robot could be realzed. he CLS means cutter locaton source whch s a standardzed tool path generated by the man processor of CAM. Further, a D prnter-lke data nterface called the preprocessor has been proposed for ndustral robots [5]. In the nterface, trangulated patch based path, zgzag or spral one can be smartly produced from SL data wthout conductng a complcated teachng task and usng a commercally provded CAD/CAM system. SL means the Stereolthography whch was proposed by D Systems and s wdely used by addtve layered manufacturng systems such as D prnters. DOI: 0.79/cae he Insttute of Industral Applcatons Engneers, Japan.

2 What we propose n ths paper s two software. he frst one s an nterpolaton method wth splne curves whch smooths CLS data. rd -order and 5 th -order splne curves are easly mplemented wth a smple lnear algebra for nterpolaton. he second one s a post processor for an ndustral robot FANUC R000C to realze a complete teachng-less operaton envronment. An early concept of robotc post processor s descrbed n [6]. On the other hand, the post-processor proposed n ths paper can drectly generate rgorous and comple FANUC robotc programs from CLS data. he program s a human-readable ASCII fle and s call LS data. As s well-known, the CLS data are made by usng ordnary CAD/CAM systems. he proposed postprocessor works as a straghtforward and cooperatve nterface between CAD/CAM systems and the ndustral robot. he convenence and usefulness of the proposed postprocessor are evaluated through a smulaton on FANUC RoboGude and an actual machnng eperment wth the robot. he FANUC RoboGude s a robotc smulaton envronment that can eecute both the robot s moton and applcaton, largely reducng the setup tme and rsk n usng an actual robot.. CLS Data Interpolaton wth Splne Curves When the target model has some curved surface, the man processor of CAD/CAM generally constructs the surface,.e., CLS data, wth mnute straght lnes by a lnear appromaton. CLS data nterpolaton s effectve to smooth such a lnear appromated trajectory.. In case of rd -order splne curve ( Fgure shows three rd -order splne curve (, and ( just passng on four ponts p, p, p and ( p ). he splne curve ( s wrtten as Where ( a t b t c t d () ( t ) [ ( y( z( ] s the splne curve n Cartesan space; a ( [ b ( by( bz( ], [ a ( ay( az( ], b ( c ( t ) [ c( cy( cz( ] and d ( t ) [ d( dy( dz( ] are the coeffcents vectors; t s the normalzed varable. When the -component s consdered, the followng relatons are obtaned from Fg.. d s fed as are calculated by () ( 0 ) p d () ( ) p a b c d (4) ( ) p 8a 4b c d (5) a b c ( ) p, so that the remanng three coeffcents 6 6 p ( ) p 0 p( ) p p ( ) p 6 Coeffcents n other two drectons are smlarly obtaned, so that the secton between (6) p and p can be nterpolated wth ( ( 0t ). By applyng ths procedure to all splne curves, the orgnal CLS data can be nterpolated for smoothng.. In case of 5 th -order splne curve Net, ffth-order splne curve s also consdered to nterpolate CLS data. Fgure shows three 5 th -order splne curves (, (, (, ( and ( just passng on s ponts p, p, p, p, p and p ( ). he splne curve p - - ( ( t ) [ ( y ( z ( ] 5 s wrtten as 4 ( a t b t c t d t e t f (7) In the same manner as the case of rd -order splne curves, when -drectonal component s consdered, the followng relatons are obtaned from Fg.. p ( p + + ( - 0 p + Fg.. rd -order splne curves for CLS data nterpolaton. ( ) p a b c d () () ( p ) ( ) 59

a 6b 8c 4d e f (8) ( ) p ( ) a b c d e f (9) ( ) p ( ) (0) p f (0) a b c d e f () ( ) p ( ) ( ) p ( ) whch leads to a 6b 8c 4d e f () 4 a 8b 7c 9d e f () Orgnal CLS data Interpolated CLS data Fg.

a b c d e 0 4 4 4 0 4 6 4 6 7 4 4 7 4 4 4 0 p( 0 p( p( 4 p ( 0 p( 0 ) ) ) ) ) p p p p p (4) Orgnal CLS data Interpolated CLS data Fg. 4. Comparson of orgnal CLS data and nterpolated ones wth 5 th -order splne curves.

An eperment of nterpolaton of a spral path was conducted wth rd - and 5 th -order splne curves. he left sde of Fg. shows the ponts n orgnal CLS data.

3 a 6b 8c 4d e f (8) ( ) p ( ) a b c d e f (9) ( ) p ( ) (0) p f (0) a b c d e f () ( ) p ( ) ( ) p ( ) whch leads to a 6b 8c 4d e f () 4 a 8b 7c 9d e f () Orgnal CLS data Interpolated CLS data Fg.. Eample of orgnal CLS data and nterpolated ones wth rd -order splne curves. a b c d e p( 0 p( p( 4 p ( 0 p( 0 ) ) ) ) ) p p p p p (4) Orgnal CLS data Interpolated CLS data Fg. 4. Comparson of orgnal CLS data and nterpolated ones wth 5 th -order splne curves. Coeffcents n other two drectons are smlarly obtaned, so that the secton between p and p can be nterpolated wth ( ( 0. An eperment of nterpolaton of a spral path was conducted wth rd - and 5 th -order splne curves. he left sde of Fg. shows the ponts n orgnal CLS data. Also, the rght sde fgure draws the ponts n the CLS data nterpolated wth rd -order splne curves. he number of nterpolated ponts wthn a secton s set to three. Fgure 4 shows another eample of 5 th -order splne curves. As can be seen, the nterpolatons are well appled to the orgnal CLS data for smoothng.. Post Processng In ths secton, a post processor s ntroduced for an ndustral robot FANUC R000C to produce a robot program wrtten wth LS format from CLS data. Fgure 5(a) s the past proposed process, n whch the machnng robot RVA could work based on CLS data generated from the man processor of CAD/CAM, wthout conductng any teachng tasks and usng robot languages [4]. Depth sensor - ( p - p - P + - ( ( p P + + ( + ( P Modelng (CAD) SL fle Preprocessor CLS fle Drect servo Machnng robot RVA (b) Proposed process Smoother PCD fle SL Generator SL fle Post-processor LS fle Machnng robot FANUC R000C (c) Proposed process Modelng (CAD) PR fle Parameter settng (CAM) Man-processor (CAM) CLS fle Drect servo Machnng robot RVA (a) Proposed process Fg.. 5 th -order splne curves for CLS data nterpolaton. Fg. 5. Flowcharts of the past developed processes and newly proposed post processor for FANUC R000C. 60

4 Fgure 5(b) s the past proposed process, n whch the preprocessor could produce zgzag-based and spral-based CLS data from SL data wthout usng commercallyprovded CAD/CAM systems [5]. Whereas the post processor proposed n ths paper s llustrated n the flow chart of Fg. 5(c). he post processor generates FUNUC robotc program called LS data from CLS data, so that desrable operaton envronment as n usng NC machne tools can be realzed for the robot. As s well-known, NC machne tools are controlled based on NC data postprocessed from CLS data. 4. About Robotc Program of FANUC R000C Seres Fgure 6 llustrates the ASCII fle format of FANUC robotc program whose fle etenson s gven by.ls. A LS fle s composed of three areas: header, program and data areas. Frst of all, the header area conssts of the followng statements. /PROG test /AR OWNER = MNEDIOR; COMMEN = Robot ; PROG SIZE = 00; CREAE = DAE IME ::50; MODIFIED = DAE IME ::50; FILE NAME = ; VERSION = 0; LINE COUN = 0; MEMORY SIZE = 8; PROEC = READ WRIE; CD: SACK SIZE = 0, ASK PRIORIY = 50, IME SLICE = 0, BUSY LAMP OFF = 0, ABOR REQUES = 0, PAUSE REQUES = 0; DEFAUL GROUP =,*,*,*,*; CONROL CODE = ; Header Area Program Area Data Area he number of lnes n the header area s fed to 0. For eample, at the lne of /PROG, the fle name of LS fle (test.ls) must be wrtten as test. At the lne of LINE COUN =, the sum of number of JP and LP n program area must be wrtten. JP and LP have smlar meanngs as G00 and G0 n NC program, respectvely. hen, the program area wth varable number of lnes s wrtten as the followng commands. :JP[] 00% CN50 ; :JP[] 00% CN50 ; :LP[] 50 mm/sec CN50 ; 4:LP[4] 50 mm/sec CN50 ; 5:LP[5] 50 mm/sec CN50 ; 6:LP[6] 50 mm/sec CN50 ; 7:LP[7] 50 mm/sec CN50 ; 8:LP[8] 50 mm/sec CN50 ; 9:LP[9] 50 mm/sec CN50 ; 0:LP[0] 50 mm/sec CN50 ; :LP[] 50 mm/sec CN50 ; :LP[] 50 mm/sec CN50 ; where JP means rapd moton lke G00 n NC program. JP s effectve to rapdly manuever an end mll to the poston near the ntal cut for removng materal. LP means feed moton wth a specfed feed rate [mm/sec] lke G0. CN50 s added to round the corner off wth a radus 50 mm. Fnally, the data area s wrtten as manly the followng poston and orentaton components n Cartesan space. he sze of the data area s also varable accordng to teachng ponts for playback moton. /POS P[] GP: UF :, U :, CONFIG : N U, 0, 0, 0, X = mm, Y =58.00 mm, Z = mm, W =4.0 deg, P =0.000 deg, R =0.000 deg ; P[] GP: UF :, U :, CONFIG : N U, 0, 0, 0, X = mm, Y =56.99 mm, Z = mm, W = deg, P =0.000 deg, R =0.000 deg ; P[] GP: UF :, U :, CONFIG : N U, 0, 0, 0, X = mm, Y =56.5 mm, Z = mm, W = deg, P =0.000 deg, R =0.000 deg ; P[4] GP: UF :, U :, CONFIG : N U, 0, 0, 0, X = mm, Y = mm, Z = mm, W = deg, P =0.000 deg, R =0.000 deg ; P[5] GP: UF :, U :, CONFIG : N U, 0, 0, 0, X = mm, Y = mm, Z = mm, W = deg, P =0.000 deg, R =0.000 deg ; Fg. 6. ASCII fle format of FANUC robotc program called LS data. where X, Y and Z are the components of a poston vector; W, P and R mean the rotatonal angles around -, y- and z- 6

aes, respectvely. UF and U are the parameters for work and tool coordnate systems, respectvely. he work and tool coordnate systems should be set n advance.

In the net secton, the proposed post processor smartly produces the above eplaned FANUC robotc program called LS data from CLS data outputted from the man process of a CAD/CAM. 5.

5 aes, respectvely. UF and U are the parameters for work and tool coordnate systems, respectvely. he work and tool coordnate systems should be set n advance. CONFIG s for the descrpton of confguraton of the ndustral robot actually used. In the net secton, the proposed post processor smartly produces the above eplaned FANUC robotc program called LS data from CLS data outputted from the man process of a CAD/CAM. 5. Post Processor to Produce FANUC Robotc Program from CLS Data format error. However, t was confrmed from the smulaton that the tp of the ball-end mll could successfully follow the zgzag-based path wthout any warnng as shown n Fg. 8. Further, a machnng eperment usng an actual ndustral robot FANUC R000C was carred out as shown n Fg. 9 by gvng FANUC robot program (LS data) postprocessed from another CLS data, so that the foamed polystyrene materal could be successfully formed nto the desgned shape. he proposed post processor yelds FANUC robot program (.LS) from CLS data. As an eample, sample CLS data vewed as Fg. 7 are lsted as GOO/0.0000,-94.88,9., , , GOO/0.0000, ,40.57, , , GOO/0.0000,-0.985,4.45, ,0.6, GOO/0.0000,-06.58,4.0, , , GOO/0.0000, ,4.95, ,0.9855, GOO/0.0000,-4.098,4.655, , , Fg. 7. A part of CLS data (zgzag path) generated from a freeformed surface desgned by CAD/CAM Creo. Where each GOO statement n CLS fle has a poston vector [ y z] and a normal vector n [n ny nz ]. hus, the rotaton angles w, p, r [deg.] n LS fle need to be calculated from the components of n. In the case of FANUC R000C, w and p are obtaned by warctan ( n,n ) (5) y p arcsn (n ) (6) where arctan and arcsn are nverse trgonometrc functons; arctan generates the angle wthn the range from z to. It should be noted that the angle r can be fedly set to 0 because of the as-symmetry of a motor spndle attached to the arm tp. An eperment of converson from CLS data shown n Fg. 7 to FANUC LS data was conducted. hen, the valdty of the converted,.e., post-processed LS data was eamned through a playback eperment on a smulaton envronment RoboGude provded by FANUC. Fgure 8 shows the smulaton result usng the model of FANUC R000C, n whch an actual trajectory of the tp of the ball-end mll s traced. If the post-processed LS data contan some nconsstency from the vewpont of the format of FANUC robotc program language, then the RoboGude warns the Fg. 8. Successful playback eperment usng LS data postprocessed from CLS data,.e., trajectory followng control of the tp of the ball-end mll. End mll Workpece FANUC R000C Fg. 9. Machnng scene of FANUC R000C dealng wth FANUC robot program post-processed from CLS data (SOLIC Co., Ltd., Omuta, Japan). 6

6 6. Conclusons In ths paper, an nterpolaton method wth splne curves has been frst proposed to smooth orgnal cutter locaton source data called CLS data. rd -order and 5 th -order splne curves were easly mplemented wth a smple lnear algebra for nterpolaton. hen, a post processor for an ndustral robot FANUC R000C has been ntroduced. Wthout conventonal teachng process, the post processor could regularly and consstently generate FANUC robotc program called LS data from cutter locaton source data called CLS data. CLS data are generally made through the man process of CAD/CAM, so that a promsng data nterface between the ndustral robot and CAD/CAM could be desgned for realzng a teachng-less operaton envronment. he effectveness and usefulness were confrmed through a playback eperment on a smulaton envronment called RoboGude and an actual machnng eperment. It s also another advantage that CLS data can be converted from SL data by usng the already developed preprocessor [5] and then LS data can be further made from the CLS data usng the proposed post processor. hs means that FANUC robotc program can be consequently constructed from SL data used wth a de facto standard for D prnters. Mechatroncs and Automaton, vol. 5, no., pp. 4 4, 05. [5] F. Nagata, K. akeshta, K. Watanabe and M.K. Habb : Generaton of trangulated patches smoothed from orgnal pont cloud data wth nose and ts applcaton to robotc machnng, Procs. of he 06 IEEE Internatonal Conference on Mechatroncs and Automaton (ICMA 06), pp , 06. [6] S.G. Andrews: Developments n post-processng for offlne robot programmng, Advances n Manufacturng echnology II, pp 65-69, 987. Acknowledgment hs work was supported by JSPS KAKENHI Grant Number JP6K060. References [] N. Xuejuan, L.Jngta, S. Le, L. Zheng and C. Xnwe : Robot D sculpturng based on etracted NURBS, Procs. of IEEE Internatonal Conference on Robotcs and Bommetcs (ROBIO007), pp , 007. [] B. Solvang, L.K. Refsahl and G. Szebg : SEP-NC based ndustral robot CAM system, Procs. of the 9th Internatonal Symposum on Robot Control (SYROCO 09), pp. 6 66, 009. [] H. Chen and W. Sheng : ransformatve CAD based ndustral robot program generaton, Robotcs and Computer-Integrated Manufacturng, vol. 7, no. 5, pp , 0. [4] F. Nagata, A. Otsuka, K. Watanabe and M.K. Habb : Machnng robot for foamed polystyrene materals usng fuzzy feed rate controller, Internatonal Journal of 6

Type-2 Fuzzy Non-uniform Rational B-spline Model with Type-2 Fuzzy Data

Type-2 Fuzzy Non-uniform Rational B-spline Model with Type-2 Fuzzy Data Malaysan Journal of Mathematcal Scences 11(S) Aprl : 35 46 (2017) Specal Issue: The 2nd Internatonal Conference and Workshop on Mathematcal Analyss (ICWOMA 2016) MALAYSIAN JOURNAL OF MATHEMATICAL SCIENCES