1.21 Digital Design and Manufacture Flashcards
(25 cards)
Define computer aided design (CAD)
CAD involves using computer software to create, modify, and optimise designs before manufacturing.
Produces 2D drawings or 3D models
Allows for precise measurements and easy edits
Commonly used in architecture, engineering, and product design
Example: Designing a smartphone case using SolidWorks or Fusion 360.
Define computer aided manufacture (CAM)
CAM uses computer software to control machinery and tools during the manufacturing process.
Converts CAD designs into machine code (like G-code)
Automates processes such as cutting, milling, or 3D printing
Increases accuracy, speed, and consistency
Example: A CNC machine cutting out parts for a bike frame using instructions from a CAM file.
Define computer numerically controlled (CNC)
CNC refers to automated control of machining tools (like drills, lathes, mills, or 3D printers) via a computer program.
Machines follow precise coded instructions (G-code) to cut, shape, or assemble parts.
Used for high-accuracy, repeatable manufacturing.
Often works in combination with CAD/CAM systems.
Example: A CNC router cutting wood into furniture components based on a CAD design.
CNC (Computer Numerical Control) machining pros and cons
✅ Pros:
High precision and repeatability – consistent results even on complex shapes
Efficient production – fast, continuous operation with minimal supervision
Reduces human error – machines follow exact instructions
Handles complex designs – can produce detailed parts not feasible manually
Easy to edit – designs can be adjusted in software without physical retooling
Safer – operators don’t need to be near moving parts as much
❌ Cons:
High initial cost – expensive machines and software
Requires skilled programmers/operators – to create and manage G-code
Less flexible than manual work – not ideal for quick one-off changes
Maintenance and repairs – breakdowns can be costly and need specialist help
Job displacement – can reduce demand for traditional manual machining skills
Name two CAM equipment
1) CNC laser cutter
2) CNC router
3) CNC miller
4) CNC lathes
5) CNC plotter cutter
CNC laser cutters
1) Covert 2D CAD designs to CNC code to move a machine head along the X and Y axes
2) Laser beam can cut or engrave materials
3) High-precision and self-finishing process
4) Requires extraction; some materials produce toxic fumes
CNC router
1) Operate on X, Y, A and Z aces to create more complex shapes
2) The workpiece is fixed to the bed of the machine
3) Requires extractiob
CNC miller
1) Moves the workpiece in the X, Y and Z axes
2) More robust than routers with slower speeds to suit metal cutting
3) Cooling lubricants can be used when cutting metal to prolong the life of the tools and give a superior finish
CNC lathes
It’s a machine that spins a piece of material (like metal or wood) really fast.
While it spins, cutting tools move against the material to shape it.
It’s mainly used to make round or cylindrical parts — like chair legs, screws, or pipes.
The CNC part means the machine follows computer instructions to cut very precisely and automatically.
CNC plotter cutter
It’s a machine that uses a sharp blade instead of a cutting tool or drill.
The blade moves over flat materials like vinyl, cardboard, paper, or thin plastic sheets.
It’s great for cutting shapes, letters, or designs precisely — often used for signs, stickers, packaging, and stencils.
The CNC means it follows computer instructions to cut exactly the shapes you want.
Simulation
Simulation in virtual modelling (in Design and Technology) is the process of using computer software to digitally test how a product, system, or material will perform under real-world conditions — before it is physically made.
What it Involves:
Running virtual tests on CAD models
Simulating forces, stresses, heat, fluid flow, movement, or user interaction
Helps identify design flaws, weaknesses, or inefficiencies early
Examples:
Testing how a chair design responds to weight
Simulating airflow over a car body (aerodynamics)
Checking if a hinge will snap under repeated movement
Advantages and disadvantages of simulations
Rapid iterations: Try multiple design variations in minutes.
Reduced cost: Less need to manufacture and test real prototypes.
Improved safety: Simulate extreme or dangerous conditions virtually.
Design optimisation: Helps make products lighter, stronger, or more efficient.
Disadvantages:
Software and hardware costs can be high (e.g. SolidWorks Simulation, ANSYS, Fusion 360).
Complexity: Requires technical skill and training to use and interpret results correctly.
Assumptions in the simulation model (e.g. perfect conditions) may differ from real-world results.
May miss real-world factors like manufacturing imperfections, user behaviour, or wear over time.
Virtual Modelling
1) The use of 3D CAD files to simulate aspects of the performance of products before they are manufactured
2) Virtual models of mechanical designs such as car engines can be checked for fit and clearance
3) CAM process can be simulated to ensure error-free machining
Computational fluid dynamics (CFD)
CFD is a type of simulation technology used in design and engineering to analyse how fluids (liquids and gases) move and interact with surfaces. It uses advanced mathematics and physics to predict flow patterns, pressure, temperature, and aerodynamics around or inside a design — all in a virtual 3D environment.
How it Works:
The product is digitally modelled using CAD software.
The fluid domain (air, water, etc.) is defined around it.
The area is divided into thousands (or millions) of tiny cells or elements (mesh).
Mathematical equations (Navier–Stokes) are applied to each element to simulate fluid movement.
What It’s Used For in DT/Product Design:
Aerodynamic testing of vehicles, helmets, tools, etc.
Ventilation and airflow inside electronics, appliances, or buildings
Cooling systems (e.g. airflow through a laptop or a fridge)
Liquid flow in containers, pipes, taps, or irrigation systems
Computational fluid dynamics (CFD) advantages and disadvantages
Advantages:
Simulates real-world flow conditions without physical tests
Helps reduce drag, improve efficiency, and identify hot spots or pressure zones
Saves time and cost by reducing the number of physical prototypes
Allows testing in extreme or impossible-to-replicate conditions
Disadvantages:
Requires high computing power
Can be technically complex and time-consuming
Accuracy depends on quality of mesh, assumptions, and boundary conditions
Not always perfect – may still need to be backed by real-world testing
Finite elements analysis (FEA)
FEA is a virtual simulation technique used to predict how a product will respond to forces, pressure, heat, vibration, or other physical effects. It works by breaking the object into thousands of tiny parts — or “finite elements” — and then using mathematics to calculate the behaviour of each one.
It’s a key tool in design, engineering, and manufacturing, especially during the development of load-bearing or structural parts.
How It Works:
A CAD model is created.
The model is divided into a mesh made of small elements (triangles or quadrilaterals in 2D, tetrahedrons or hexahedrons in 3D).
Forces or constraints (e.g. weight, torque, temperature) are applied.
The software simulates how the model reacts — showing deformation, stress points, or failure zones.
FEA advantages and disadvantages
Advantages:
Identifies weak spots and improves safety early in design
Reduces the need for physical prototypes
Allows testing of multiple scenarios (materials, forces, shapes)
Saves time and cost during product development
Encourages sustainable design by reducing waste
Disadvantages:
Results can be inaccurate if mesh quality or inputs are poor
Requires specialist software (e.g. SolidWorks Simulation, ANSYS, Autodesk Nastran)
Needs technical expertise to interpret results correctly
Doesn’t always account for real-world variables like wear, friction, or human use
Rapid prototyping
Rapid prototyping is the process of quickly creating a physical model or prototype of a design using computer-aided design (CAD) data — often via 3D printing or CNC machining. It helps designers and engineers test, refine, and communicate ideas faster than traditional model-making methods.
How It Works:
A 3D CAD model is created.
The model is exported (usually as an STL file).
A rapid prototyping machine — such as a 3D printer, laser cutter, or CNC mill — builds the model layer by layer or through subtractive processes.
The prototype is reviewed, tested, and iterated upon if needed.
Rapid prototyping advantages and disadvantages
Advantages:
Speeds up product development
Encourages frequent testing and iteration
Allows early user feedback before mass production
Reduces costs of tooling for early models
Improves communication of ideas to clients or stakeholders
Disadvantages:
Prototype materials may not reflect final product performance
Surface finish and detail may be lower than production quality
Some methods can be expensive for large or complex models
May lead to over-reliance on visual accuracy rather than functional testing
Electronic point of sale (EPOS)
EPOS is a computer-based system used by retailers and manufacturers to record sales transactions, manage stock levels, and track customer data in real time. It’s commonly used at the checkout in shops and can link directly to inventory control systems, helping with demand forecasting and stock management.
What It Includes:
Barcode scanner
Cash register or card reader
Receipt printer
Computer or tablet with EPOS software
How It Works in Product Design & Manufacturing:
When a product is sold, the EPOS system automatically updates stock levels.
Sales data can be used to identify popular products, seasonal trends, or slow-moving items.
This data informs production schedules, restocking, and marketing decisions.
EPOS advantages and disadvantages
Advantages:
Accurate, real-time sales tracking
Helps manufacturers respond with Just-in-Time (JiT) restocking
Reduces waste and overproduction
Provides data insights for product improvement and demand planning
Can integrate with supply chain systems
Disadvantages:
Expensive to set up and maintain for small businesses
Can be disrupted by technical issues or outages
Requires training for staff to use properly
Data privacy and cybersecurity need careful handling
Product, planning and control (PPC)
PPC is a management process used in manufacturing and production to ensure that products are made on time, within budget, and to the required quality. It involves planning, scheduling, and controlling all aspects of production from raw materials to finished goods.
Key Elements of PPC:
Product Planning:
Deciding what to produce, when, how much, and with what resources. This includes forecasting demand, selecting materials, and planning production capacity.
Production Scheduling:
Creating a timetable for production processes, machine use, and labour allocation to meet deadlines efficiently.
Inventory Control:
Managing raw materials, components, and finished goods stock to avoid shortages or overstocking.
Quality Control:
Ensuring products meet design and safety standards throughout the production process.
Monitoring & Feedback:
Tracking production progress and solving issues to keep things on track.
PPC advantages and disadvantages
Advantages:
Ensures efficient use of resources (time, materials, labour).
Helps meet delivery deadlines and customer expectations.
Minimizes waste and costs by optimizing inventory and processes.
Supports flexibility to respond to changes in demand or problems.
Disadvantages:
Requires accurate data and effective communication.
Can be complex and time-consuming to set up and manage.
Poor planning can lead to production delays or excess stock.
Depends on staff cooperation and reliable equipment.
Radio frequency identification (RFID) tags
RFID tags are small electronic devices used to automatically identify and track objects using radio waves. They are widely used in manufacturing, retail, logistics, and supply chain management to monitor products and materials in real time.
How RFID Works:
An RFID tag (attached to an item) contains a microchip and an antenna.
A nearby RFID reader sends out radio waves.
The tag responds by sending back its unique ID and data.
The reader collects the information and sends it to a computer system for processing.
