Take some advice and use an established designer!
A working model will really impress and prove viability!
Design & Development
Stephen Frazer, Frazer
Design Consultants Ltd. www.frazerdesigners.com 020 7624 6011
Designing and prototypes
Alistair Swanwick Bsc.(hons) Engineering product design. www.innovate-design 020 7354 5640
Mark A. Lee, product design
from concept to prototype
Prototyping Services
Ian Coker MIPI , Persevere
Engineering solutions Ltd., www.workingmodel.co.uk, 01580 830 087
also see how your local college or university can help Colleges and Universities