When deciding what to design for our final year project, we had several ideas in which we had an interest. Some of which included: a home maintenance system, the perfect beer, a PID controlled water thermostat/heater/overflow system and a self-maintained gardening system. Due to the increasing non-originality and inappropriateness of some of our ideas, we elected to improve the garage door. This seemingly simple idea was chosen so that the need for tedious tasks such as pressing buttons could be eliminated. As we are constantly losing our remote controls, we were adamant that we could pursue an investigation into a better alternative. As we are not fond of the idea of permanently attaching small boxes to our dashboards, we decided to automate the process.

Remote controls and garage door keys are usually left in the car and are prime targets for thieves. Our product would be discrete and become part of the car which would not be visible and prone to thefts from the vehicle.

Early stages

When we first thought of the idea of automating the process of opening a garage door without the use of remote controls, we planned to open the door only if the correct weight of the car was found by a weigh bridge. This would also have used some form of transmitter/receiver to detect the car but the main focus would have involved the use of fibre optics. This would be obtained by measuring the bending losses of light as a force (ie weight of the car) was placed upon a spring-mounted plate. Although this technically challenging project seemed a perfect test for a final year project, its ineffectiveness in commercial viability deemed this alternative to be omitted from further investigation.

We then chose another alternative, using sensors. This new idea used four beam sensors, similar to those you would find in an entrance to a shop, without the beep sound. This idea was submitted and approved as our project. As time progressed, we decided (mainly due to financial status as a result of being a student under the Howard Government) to decrease the number of sensors (valued at a minimum of $100 each) from four to three. This meant that two of the beam sensors that would be used for the car to leave would be replaced by a motion sensor that when triggered would allow the sequence for detection of the car to begin. We also decided to replace the sensor at the gate with another motion sensor above the door.

Finalising Decisions

The replacement of these of sensors was also due to the fact that two people or objects could fool the program into opening the door. Motion sensors allowed the car to leave and enter whether or not a stationary object was in the way. This concept of people triggering the door did not disappear with the idea of motion sensors, and with some lateral thinking led to the idea of powering the on-car chip with the auxiliary power from the car.