The main element of this design will be the secure connector that becomes locked together both around the body and then around the bike.
This connector must be secure enough to give the customer peace of mind while their bike is locked up away from them. It must also be both soft and light enough to be worn comfortably as a belt around one's waist.
There are many portable locks that provide a minimum amount of protection for quick trips to the shop, that are both portable and light weight. There is also new technology on the market called Boaflexicore®, this is a patented technology that is currently availlable for pre-order having had a sucessful run on Kickstarter.
“By harnessing the unique security properties of multiple innovative lightweight materials we created a composite strap called Boaflexicore®. Each layer provides additional security, meaning it can withstand sustained attack from tools like cable cutters, bolt croppers and hacksaws.” (Lightweight bike lock | light bike lock, no date)
As there is little to no information available online for the material properties for the Boaflexicore® I have taken my research into strong lightweight materials. I have also looked into 'strong textiles'.
The most commonly used fibre is Kevlar. "Kevlar was made many decades ago and has proven to be one of the strongest materials on earth. It is used in both bulletproof and stab proof vests. Kevlar fibres are strong on their own, but when they are woven together tightly they create a protective barrier. The tight weaving of the fibres makes it very difficult for someone to be able to penetrate the material because it takes so much force to actually penetrate through the material." (Terms and Policy, 2016)
Graphene Is also a very lightweight, strong material, this, however, is still very expensive to produce and potentially not an option for such a mass market product. (Blakemore, 2015)
Joining of Boaflexicore® will be a key consideration for this design. Should the Boaflexicore®, not be able to be attached to itself then the design will need to consider the option of having the cord internal to the metal housing.
For now I will direct my research towards methods for joining the end back to itself once it has been looped through the metal housing unit.
Having come across an ADHESIVE process FOR NYLON & KEVLAR called Polyamide adhesion where dissimilar materials form structural bonds I feel confident that Boaflexicore®, will be secure upon joining. The exact bonding agent is described here:
"If exceptional chemical resistance is desired, we would recommend the BONDiTTM B-481 or B-4811. These adhesives provide toughness, non-brittleness, chemical resistance such as exposure to chemical (dry) cleaning, hot water washing and drying cycles, and steam, including autoclaving." (RELTEK, 2014)
TermsSafeGuardCLOTHING™ and Policy, C.S.P. (2016) How does a stab proof vest work? Available at: http://www.safeguardclothing.co.uk/articles/how-does-a-stab-proof-vest-work/ (Accessed: 8 May 2016).
RELTEK (2014) ADHESIVES for nylon. Available at: http://reltekllc.com/adhesivesfornylon.aspx (Accessed: 8 May 2016).
Lightweight bike lock | light bike lock (no date) Available at: http://www.litelok.com/ (Accessed: 1 May 2016).
Blakemore, E. (2015) Metal as light as styrofoam and as strong as titanium — and 5 other amazing new materials. Available at: http://theweek.com/articles/582787/metal-light-styrofoam-strong-titanium--5-other-amazing-new-materials (Accessed: 11 May 2016).