Ergonomics ( how is it going to be held and used, carried, comfort, size to fit in the hand / wear / ride on ... etc )
Materials that could be used ( suitability, strength, qualities for the job )
Colours
Surface textures
Joining of materials
Safety
How it will be used.
Research notes
3D exploded drawings
2D working orthographic drawings
2D cross sectional drawings
Models
Photographs
Computer design
Rendered 3D drawings ( either by hand or on the computer )
What designs and elements are the best ones to develop further?
What materials are going to be best to use for each design?
What properties do the materials need to have to fulfil their function within the design?
What construction methods are the best to use?
What do you have to consider in terms of safety, number of people using the design, ergonomics and fitness for purpose?
Use an ergonome and your anthropometric data from your research to get the proportions correct of some your development drawings.
How are you going to ensure that the design is robust enough to withstand being used.
Client feedback.
Part of the job of developing your designs is to work out how they would be put together and what they would be made from.
The two drawing methods shown here show how a design is put together and assembled.
Another way of working out whether a design could work is functional modelling.
Test ideas for the overall shape.
Test ideas for individual elements of the design.
Analyse and report on your findings at each stage.
Materials to use - card / plasticine / tinkercad / polystyrene blocks etc.....
You can also do functional modelling online using programmes such as Tinkercad. Elements can be 3D printed or laser cut or you can do a screen cast video or screen shots of your design turning round on the computer screen.
Make sure to photograph / screen shot each development, and put the pictures onto a doc to write analysis notes with them.