Gallery > Consumer goods > Timer knob test model

Create a prototype for ergonomic testing

Rapid Prototype of a new timer knob in a freeform design

In this project DeskProto has been used for a pure Rapid Prototyping application. A special rotating knob has been designed, to be used as a timer knob an artificial sun apparatus. The outer form of the knob clearly suggest the action to be taken to set the timing device: a nice piece of ergonomically sound design.

The design of the knob was done in Pro Engineer (tm), and before actually clearing the design for production it was needed to perform a series of ergonomic tests. Such tests can only be done using physical prototypes: real persons then can operate the new product and evaluate it's shape.

As you can see in the quality of the images this is an old project: one of the first DeskProto projects ever: in 1995, using DeskProto Version 1.




DeskProto has been used to rapidly create the prototype that was needed. The milling parameters to be set were the milling tool to be used (a ball nose cutter R 3 mm), and the accuracy (distance between the toolpaths 0.4 mm). The prototype than was milled from a massive block in about one hour, using a Roland CAMM-3 desktop milling machine.

Note that a massive (solid) prototype has been milled, which is sufficient to evaluate the outer form of the product. The material used is called 'Cibatool' (inside the USA called 'Renshape', both names tm), which is a 'wood-like' model material. It is very easy to finish a Cibatool prototype, creating a perfect glossy surface.

The design of this timer knob was created by Dutch design bureau Well Design in Utrecht (NL). We received an STL file from their Pro-E system, the prototype has been milled in our own mechanical workshop. Our contractor in this case was a toolmaking company:
'Gereedschapsmakerij Mutsaers' in Tilburg, the Netherlands. This company afterwards also manufactured the production tools for the timer knob (injection moulding).