- Wrapper – Use a wrapper to adapt a third party part to your contract. If you use the supplier's interface as your contractual interface, any change in either product or supplier will probably cause you to redesign the interface, a potentially expensive undertaking.
- Facade – Use a façade, a connector of connectors with a simple interface, whenever multiple wires (like data & power) need to go to the same place.
- Singleton – Every component needs power, data and ground. The first thing every engineer wants to create when designing a new component is the power, data and ground bus. The singleton pattern says for each basis component, there is just one in use. So if you need a power-data-ground bus - use ours!
Sometimes the patterns have a cost. The wrapper pattern added 8 kg to the weight of a WIKISPEED car, for example by adding an extra slab of aluminum between the chassis and the suspension.
Was the design pattern worth the extra weight? Yes, because that pattern allowed Team WIKISPEED to a) reduce several hundred pounds from the weight of the car by steady optimization, and b) react easily and cheaply to the changing suspension requirements. Had they not been able to do that, they would not have been able to participate in the final selection round.
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