THE SPECIFIER

a design-specification tool

Useful in the process of industrial-design prototyping.
Specification using mouse and keyboard on an orthogonal 3D grid.
Spec is visualised assuming single camera with coincident light-source.

Easy to start using (simple UI developed using Ergonomix ).
Produced by Khitchdee Design.

Specification

There are 2 aspects to the specification of a land-vehicle design.
1. A structural specification, which is a static description of the built up structure of a design.
It includes a specification of each part in a design,
how the parts connect with each other,
and a structural model of the user (if applicable).
Specification is done using the mouse and keyboard input.
2. A construction-process specification, which specifies the construction-process of a design.
This is useful for an assembler or a fabricator.
This will be implemented as a frame-by-frame visualisation of a dynamic model.

Visualisation

A Visualiser implements perspective-correct display-screen mapping of modelled 3D objects.
It models a camera with a location and orientation,
and a single light source, at the same orientation and location as the camera.

For visualisation, a 3D object is represented as a set of 3D planar segments.
These 3D planar segments are mapped onto a 2D screen using 4-point plane-mapping.
A curved planes (in 3D) is modelled as a lattice of flat planes.
The visualiser uses only the device's (2D) drawing engine,
and targets a visualisation time of 100ms/frame
for a bicycle-model at 4K resolution on an iPhone 15Pro class device.

Construction-process specification (planned)

We plan to produce a component for the specification of a construction-processes.
The designer will identify several construction states in the construction process.
Each construction state will be a physical model of the relative placement of the components and tools in the process.
They will then indicate transitions between states.
The construction-process specifier will use these construction states and transitions between them
to create an interpolated sequence of models to be visualised.
This sequence will be visualised using the Visualiser with some animation controls
(in addition to the Visualiser's camera controls).

Photograph assisted specification (planned)

After the mouse and keyboard specification interface,
we plan to produce an additional interface,
based on pictures of an under-development prototype and its components.
This will increase specification-process efficiency.

1. A designer loads photographs of a real object into the app
   (with a description of the approximate camera parameters used in taking those photographs).
2. Identifies (in terms of 2D point descriptions) the components in the structure of the object in the photograph.
3. For each component, they describe its 3D orientation and size, based on physical measurements.

Bicycle Structural Overview

A bicycle is specified as:
A. The primary frame and components

1. A frame consisting of:
   A head-tube, top-tube, down-tube and seat-tube.
   A seat-stay and a chain-stay at the back.
   A bottom bracket at the base of the frame.
   Connectors that connect the parts in the frame.
2. The front fork and handle-bar
3. The chain-drive consisting of:
   a chain crank and pedals
   a freewheel
   a chain
4. The front-wheel, front-wheel spindle and tire
5. The rear-wheel, rear-wheel spindle and freewheel attachment, and tire.

B. Attachment specifications between the primary frame and component.

C. The braking system and optional gear-ratio control systems

1. A braking system and its attachment mechanism
2. A gear-ratio control system and its attachment machanism