July 7, 2010
A customised rapid prototyping system was developed by IDC Models, the rapid prototyping and model making division of Industrial Design Consultancy, to produce a dummy hand for testing mobile phones. The brief from IndexSAR, which specialises in performance testing wireless systems, was to produce a model of a human hand which would incorporate carbon black to absorb the radio waves emitted by mobile phones during testing.
     The difficulty was in achieving an even distribution of carbon throughout the model. The carbon powder can become very thick when mixed making it difficult to manipulate and creating air pockets within the mould. The hand was moulded in polyurethene elastomer to allow the fingers to flex and curve around a phone regardless of its shape or size. The technique settled on was a moulding system which encompassed half pressure casting and half vacuum-casting. The company's in-house stereolithography machine was used to produce durable master 3D parts from which to make the moulds, which also reduced lead times.
     IDC Models has produced more than 20 phantom hand models for Indexsar in a variety of sizes according to the mobile phone design.