1.7 Digital Design and Manufacture Flashcards
What are some advantages of using CAD compared to hand generated alternatives?
- Save time and money
- Improve accuracy
- Designs can be edited
- Experimental changes made quickly
What can a pattern design system (PDS) do?
- Draft and grade pattern pieces
- Produce lay plans
- Send the information to a computer integrated automated cutting system
What is virtual modelling software an advantage of CAD?
Replaces the need to hand make physical samples, which has less impact on the environment
What is more accurate by using CAD?
Designs and developments are more accurate, pattern pieces can be retrieved from a. database and printed out in pristine condition
What are the disadvantages of using CAD compared to hand generated alternatives?
- Inital set up costs high
- Client, designer and manufacturer all need to have compatible IT systems
- Systems require regular updates and technical support
- Potential for cyber attacks
What can CAD be used for?
Generate and accelerate the development of product design and pattern ideas for fabric
How does CAD show designs?
With photorealistic rendering and manipulated scanned artwork
How doses CAD stimulate idea interactively?
3D models can be viewed from any angle, allowing errors to be detected and corrected at an early stage
How does CAD show its final ideas?
On a presentation board to collect client and marketing feedback, it can also present ideas by email so it speeds up the decision making
What is an input?
A motif or design can be scanned into the computer, if is then ready to be altered
What is a transformation?
The computer can make many different repeats and combinations very quickly
What is an output?
Presentation boards giving a good idea of what fabric will look like or a range of garments
What are industrial applications of CAD able to do?
Show ideas in different colour ways using a pantone colour palette, imagine mapping or as a virtual prototype
What is pantone?
A standardised colour matching system
What is image mapping?
Allows a designer to show how a pattern or colour might look on a garment
What are some industrial features of CAD?
- Plan and create accurate pattern repeats for printed fabrics
- Create accurate pattern templates form 3D models using PDS
- Plan accurate and correct lay plans to maximise profit and minimise wastage
What does CAD send?
Complex information directly to CAM machines, for example laser cutter and CAM embroidery machines
What needs to happen for CAD and CAM to work together?
The CAD files need to be converged info special code using a computer numerically controlled program
What is computer numerical control?
A program, converted form CAD files, which uses special codes to control CAM equipment
Why is CAM often used for felalcd manual operations?
- Machines can work quickly and continuously
- Quality more consistent
- Machines can work with materials and chemicals that might be harmful to humans
What are computer controlled weaving looms programmed to do?
Lift the correct warp yarns to allow the insertion of weft yarns to create different weaves
What are the main methods used?
- The gripper system
- The rapier system
- Jet systems
What is the gripper system?
Several grilled projectiles that take it in turns to launch and carry an individual weft yarn at high speed, in the same direction, across the loom
What is the rapier system?
A rod with a gripper that takes the weft to the centre of the loom where a second rod picks it up and carries it to the opposite side
What are jet systems?
Use water or pressurised air to insert the weft by carrying it across the width of the fabric
What are other CAM machines controlled by computers?
- Weft and warp knitting machines
- Circular knitting machines
- Highly specialised machines, which produce seamless garments
- Jacquard weaving and knitting machines
What is CAD software used for?
To develop print designs and individual screens for screen printing
What is CAM software used for?
Controls the movement of the fabric, the supply of dye and the movement of the screens
Why should a lay plan be used?
- Minimum wastage
- Different garment sizes cut together
- All pattern pieces cut out
- Any pattern, one way design or nap in the fabric is taken into account
- Pattern pieces cut on grain
What is done to save time and money?
Many layers do fabric are spread and cut out at the same time
What do computer controlled speaking machines guarantee?
That the fabric edges are laid exactly on top of each other and the patterns on woven or knitted fabric are used in the same place on each layer
What do computer controlled cutting machines use?
- Knives
- Laser beams
- High pressure water jets
How are barcodes used?
- Cut out pieces put into bundles and labelled with barcode then sent to sewing
- Computers read barcodes and monitor each products progress throughout manufacture
What do automatic buttonhole machines use?
CNC machines programmed to accurately shape and repeatedly make buttonholes of the same shape and size
What does a profile sewing system use?
A jig and a template to automatically place and stitch patch pockets onto garments
How are pockets sewed?
- Flat pocket hemmed at top edge then fed into template and positioned in exact place to be stitched
- Edges are automatically folded under and a jig holds the pocket down while the machine stitches it
What can an automated CNC profile machine be programmed to stitch?
Different seam types, for example fell seams in the legs of trousers
What can computers control?
Pressing during manufacture and on garment completion
What are automated conveyor fusing presses programmed to do?
Give an even finishing when fusing interfacing
What is a steam dolly?
A specialist pressing machine that uses steam and air to inflate the inside of clothes, making creases fall out
What decorative processes can computer controlled machines produce?
Logos and embroidery quickly and accurately using many different coloured threads
What can lasers be programmed to do?
Using CAD software to etch or cut out intricate patterns on most fabrics, the laser seals the edges at the same time as it cuts, stopping edges from fraying
What can computer software simulate?
A proposed production system to check production is possible before changing the layout of a factory or investing in new equipment
What can simulations do?
- Indicate how long it will take to manufacture a product
- Model sales projections, enabling companies to be ready to react to consumer demand
What does a PDS help?
With the design of garments and the development of pattern templates
What can a PDS be used to do?
Present images and virtual prototypes to clients as it can simulate fabric texture, drape and garment fit on realistic, virtual body forms
What can PDS create?
A customised fit using data from 3D body scanners or measurements taken by hand, so a customer can see how a garment might look and drape on their body
What does digital printing allow?
Designers to quickly test out fabric designs by printing short lengths of fabric directly from a CAD program
What do physical samples help?
Designers check the print works with a fabrics surface texture and weight
What is electronic data interchange?
A system that relies on the use of computers to electronically exchange all documents
What do EDI networks analyse?
Consumer trends and use the information to meet consumer demand
What is electronic point of sale (EPOS)?
A computer based scanner barcode system used to read barcode information as well as capture data when products are purchased
What are the advantages of an EPOS system?
- Stock levels easily monitored
- Demand activated manufacture more suitable
- Saves money
- Sales data and customer details collected for use by marketing departments
What do computers in a PPC network do?
Plan and control all aspects of manufacturing
What are the advantages of PPC networking?
- Centrally stored information
- Improved control of ‘in time’ availability in the supply of materials
- Efficient planning of processes
- Manage capacity
- Efficient planning for style changes
- Fewer production stoppages
- Track order
What are PPC systems used to do?
Coordinate different delivery dates to ensure that all materials and components are available using a JIT system, these systems keeps track of what has been ordered and when it will be delivered
What is it possible with a PPC system?
Constantly monitor the status of orders and track orders throughout the supply chain
