Project Overview An introduction to 3D printing Designing 3D printing parts Redesigning the Clawbot 3D printing new Claw components Assembling & Testing 3D printed components Open 3D printing design challenge

LESSON 02

Lesson 02 Starter Learning objective: Be able to confidently sketch existing components parts for the VEX robotics system, adapt existing parts through sketching to develop new parts, and sketch in context to demonstrate how parts will work. Before we can design new VEX parts, we should spend a short time period considering the study of existing common VEX parts. For the starter task, you are challenged to sketch in 2D, 3D, isometric or model in blue foam, the following parts: A flat bearing A 60 tooth gear A claw finger Key words: Isometric, 2D, 3D, Model

Designing 3D printed parts Sketching existing parts – 2 point perspective technique x The steps: To draw a 3D “crate” into which you can sketch your parts you need to… 1. Mark two vanishing points (on the same line) 2. Draw a centre line (lightly) 3. Mark a wide V to the points 4. Mark a second wider V above, again to the points 5. Mark an X above this, again to the points 6. Mark two vertical sides from the ends of the X. (depending on the vertical distance between the V, V and X you will find that the crate you end up with is different in height) Key words: crate, vertical, horizontal, vanishing point, 2 point perspective.

Designing 3D printed parts Sketch onto existing parts modifications you might make Onto your 3D sketches, sketch out new ideas and modifications that you could make to these parts by adding or removing materials. If you can focus on a purpose or outcome at this stage, excellent!

Designing 3D printed parts What is wrong with the clawbot? Task: Analyse in teams the clawbot by using the product. Analyse the build approach you took, the aesthetic design, the functional operation, and carry out a brief sack collection and scoring task into a trough or similar tray high up. Identify the issues, and consider how: A. Existing parts could be modified to be better at their job B. New parts could be designed to improve the function of the clawbot.

Designing 3D printed parts Using the tools in Autodesk Inventor… A single shape pulled up to create a solid, or pulled into a solid to create a cut A single shape spun around an axis or edge to create a solid in the shapes path. A single shape normally a circle, drawn onto a flat surface and drawn into or through a solid. A curve applied to edges using a given radius. An angled cut applied along an edge. Letters applied as a sketch to a surface and then either cut into or extruded off from a surface. A wall thickness applied inside a shape but removing all other materials to create a shell. A pattern of shapes created by selecting a single feature on a surface, and multiplying it.

Designing 3D printed parts Modifying existing parts to create new parts: Gear

Designing 3D printed parts Modifying existing parts to create new parts: Bearing

Designing 3D printed parts Modifying existing parts to create new parts: Claw finger

Designing 3D printed parts Sketching in context: the clawbot If we use CAD and model in context, it involves building new parts on the screen by working around existing parts. For example a USB pen PCB drive would appear on screen, and around it the designer would add material to produce a casing. In a similar fashion, you can sketch over an existing product to develop design solutions, and often it can be an effective and quick way to show ideas without having to draw the entire product out. Task: sketch over, around and to the side some modifications that would improve this clawbot, in your opinion. Sketch sheet Print these templates on A3 paper and sketch over them with pencil or bold pen/marker

Designing 3D printed parts Sketching in context: the clawbot In this example you can see lots of different types of sketching. Sketch functional parts Here the part is designed to hold the motor and motor control wires so that they remain connected Sketch adaptors Here a part that holds a blade for cutting wires Sketch claws Here the existing claw has been modified to hold larger objects with more surface contact. Sketch aesthetic parts Here a wheel cover has been designed for the 4 inch wheels Sketch supports Here an additional frame would provide a wheel to stop the claw tipping over. Sketch protectors Here the part stops sacks getting stuck under the wheels Sketch modified wheels Here the wheel has been designed with extra teeth to dig in to soil

Lesson 02 Plenary As a class, let us consider the following questions? A. What styles of sketching work better for designing 3D printable parts in VEX? B. Why is sketching to start with better than moving directly to CAD? C. What limitations did you identify in your sketching ability? D. How could you improve your sketching over time?

Summary Today you have: Learning objective: Be able to confidently sketch existing components parts for the VEX robotics system, adapt existing parts through sketching to develop new parts, and sketch in context to demonstrate how parts will work. Today you have: Learnt about a sketching technique that will support your communication skills Adapted the designs of others to improve your own ideas about design Developed an ability to communicate to others effectively