1. Digital Knitting A New Perspective for Knitting Industry Jimmy K.C. Lam., Jin-yun Zhou Institute of Textiles & Clothing The Hong Kong Polytechnic University

2. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 2 Outlines Introduction and Background SDS-One Design Concept Yarn and Textile Design from SDS-ONE Knitted Stitch Design and Loop Simulation Knit CAD System Garment Simulation and Mesh Mapping Whole Garment Making Concept Conclusions

3. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 3 Introduction & Backgrounds 1 Since the introduction of seamless garment knitting techniques on V-bed machines in 1995, this technology has been considered an innovative process and is currently growing in its commercial application around the world (1) By eliminating the cutting and sewing processes, complete garment knitting provides a variety of advantages of knitting production such as savings in cost and time, higher productivity, quick response production (2,3,4)

4. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 4 Evolution of modern flat- bed knitting

5. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 5 Introduction & Backgrounds 2 Recent ITMA exhibition in Munch (5) showed that both Stoll and Shima Seiki continue to advance their technology on computer knitting on flat bed industry. The new M1 Plus from Stoll CAD system integrates knit editor, knit shaper, Sintral Checker and Knit and Wear module into one seamless CAD/CAM design centre. Shima Seiki also develops her own SDS-ONE- APEX CAD/Cam system and offers true 3D visual knitting from fabric design, visual knitting and fabric simulation to 3-D whole garment knitting.

6. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 6 Introduction & Backgrounds 3 This paper discusses the latest development from Shima Seiki on digital knitting in SDS-ONE design system. The whole paper will be divided into five sections. –Section one: The concept of virtual sampling; –Section two: Yarn and textile design; –Section three: knitted stitch design and loop simulation; –Section four: Knit-CAD system; –Section five: Garment Simulation and Mesh Mapping

7. Section One SDS-ONE Design Concept- an integrated approach

8. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 8 SDS-ONE Design Concept SDS-ONE is the “all-in-one” apparel design tool that directly turns the designer’s concepts and ideals into products. All information that is necessary for apparel production, from product planning, designing, sample production, manufacturing through to product promotion integrated in one. SDS-ONE is also a communication tool for bringing together people and ideas from different areas of fashion industry. From the yarn maker, apparel planner, designer, knitter, merchandiser and retailer, design decision and concept can be communicated throughout the supply chain.

9. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 9 Integrated approach from SDS-ONE CAD system

10. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 10 One of the advantages of SDS-ONE is the “virtual sample production”. Conventional time-consuming sample making is eliminated. Product sample is created on this system directly with a wide spectrum of functions. Repeated simulation is possible (for different yarn, colour, stitch density) which can significantly reduce the production lead time.

11. Section Two Yarn and Textile Design from SDS-ONE system

12. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 12 Yarn and Textile Design Yarn Design SDS-ONE starts the design from material, the virtual knitted yarn Special functions like “yarn twisting”, “slub”, melange”, “space dyeing” or scanning directly from knitted yarn are available. Yarn can be controlled by thickness, hairiness, twisting to simulate different texture on a virtual knitted fabric. Real yarn can be input directly from SDS-ONE with its unique two pass scanning system.

13. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 13 Yarn Design from SDS- ONE system

14. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 14 Yarn and Textile Design Textile Design SDS-ONE comes with library to generate different design from simple, basic motif. It allows the creativity of designer by experiments with different automated generated pattern such as “polka dota”, “argle”, “stripe”, “kaleido”, “wave and whirl” and “ mandel”. Data can be used for jacquard, intarsia, and even fed into on demand printing system to be printed directly onto knitwear.

15. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 15 Pattern Design from SDS-ONE

16. Section Three Knit Stitch Design and Loop Simulation

17. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 17 Knitted Stitch Design and Loop Simulation The SDS-ONE CAD system holds abundant structure pattern enables the simulated of varied knitted pattern. All those simulated images (visual knitting) will be automatic converted into Shima Seiki knitting language (colour control and option line for machine control).

18. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 18 Knitted Structure Library in SDS-ONE

19. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 19 Knitted Stitch Design and Loop Simulation Loop Simulation Loop simulation allows quick evaluation of virtual knitwear without sample making. Various simulation can be done for Whole Garment, conventional flat bed knitting. Knit design created in Design program is automatically converted into knit programme data so that designer and technician can keep in close communication.

20. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 20 Loop Simulation under SDS-ONE system

21. Section Four Knit CAD system

22. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 22 Knit CAD system The Knit CAD system under SDS-ONE converts the designer concept from virtual loop simulation into different knitting instructions for Shima Seiki. No programming language is required as the automatic software from Knit CAD system convert the entire package directly into knitting language for Shima machine.

23. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 23 Package generation under Knit CAD automatic software

24. Section Five Garment Simulation and Mesh Mapping

25. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 25 Garment Simulation and Mesh Mapping Realistic 3D garment simulation can be done directly on SDS-ONE system before actual production. Different effect (lighting, texture, colour) can be controlled for simulation and mapping.

26. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 26 Temple Mapping for Quick Simulation

27. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 27 Garment Simulation under SDS-ONE system Original PhotoMesh Mapping with simulated fabric

28. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 28 Whole Garment Production Concept This knitting technology enables knitting of finished articles in a full fashion shape. This means, for example, that entire sweaters can be knit and worn immediately without additional sewing work after removal from the machine. With knit and wear the individual body and sleeve parts are knit like a tube in the proper shape. These individual parts are knit together in the machine with widening, narrowing and certain binding-off techniques so that a finished article of clothing is produced.

29. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 29 Whole Garment Making Three separate tubes are created for WG

30. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 30 These three tubes are combined into one for further knitting

31. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 31 V-neck is formed by separated knitting with 3 feeders

32. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 32 Conclusions This paper reviewed the new digital CAD development cycle for SDS-ONE Shima Seiki system on electronic V-bed knitting machine. The new system combines the yarn design, fabric design, knit loop simulation into one integrated CAD system. The CAD solution can be either directly output to Shima Seiki knitting machine for production (Knit CAD software) or indirectly display on computer monitor for 3D virtual garment simulation with different texture or mesh mapping technique. The new digital CAD system today can significantly shorten the development and production cycle for knitwear industry.

33. AUTEX 2009 World Textile Conference, 26-28 May 2009, Izmir, Turkey 33 Acknowledgements The authors like to thank for the Institute of Textiles & Clothing, the Hong Kong Polytechnic University for staff development funding for this conference.