Specifications

56
quantity for purchase
Semi Conductor
Low cost
Easy to obtain
Matured technology
(More resources
available)
Available for single
sensor purchase
Found to be less
accurate compared
to fuel cell sensors
Hard to calibrate
Fuel cell sensors are clearly marked to be a better sensor and the potential for a
better product design, but it certainly posses a great challenge for us with its
cons as a result, Semi Conductor sensors might more realistic and practical for
our design. Majority of the fuel cell sensor manufacturers are based in England,
thus further increases the communication and cost issues for us. Till date, we
have established continues communication with two fuel cell sensor companies
and very little has came out of it. On the contrary, two different models of semi-
conductor sensors, MQ-3 and MR513 alcohol sensors were purchased for further
in depth profiling to guarantee the compatibility of our system’s overall design.
2.11 Battery
One of the requirements for this project is that the personal unit be portable.
While the portable unit will be connected to the base unit in order to
communicate values for the base unit to decide interlock status, it should also
work independently. In order to achieve this, a portable power source is needed.
While on-demand power generation may work in certain cases, it would not be
appropriate for this project. Solar power would be closest to being viable for a
small, handheld unit; however, due to the common practice of consuming alcohol
at night, or in indoor areas away from sunlight, it would not be an effective source
of power.
As such, the only viable option left is to use a battery. However, even within this
choice, there are several more considerations to be made in order to fit within the
overall design requirements of the project. A primary concern about the battery is
its size. As the goal is to reduce the size of the portable unit as much as possible,
it cannot be so large as to defeat the portable nature of the unit. In addition, it
must also be of an acceptable weight. An excessively heavy portable unit will
discourage use of the product and will be “left behind,” whether at the user’s
home or vehicle – thus again defeating any portable purpose to the portable unit.
It must be low cost not just for an initial purchase, but as a continuing expense
for the user. In addition, it must continue to perform for a fair period of time.
Safety is also a concern as the device will be used most often by intoxicated
individuals; advanced steps to operate the device (for safety reasons) cannot be
introduced for this reason.