Tutorial - Installation and Car Speed Tracking Application
Car Speed Tracking IoT Application
We motivate TTPython’s flexibility in designing distributed, energy-constrained, and time sensitive applications with an IoT application: a car speed tracking application that utilizes two magnetometers to detect a car on a road. The magnetometers are spaced apart at a known distance, and the two sensors can provide the time taken for car detection between the two sensors.
We’ll walk through how one would design this application and how TTPython captures necessary details developers need to consider in large-scale IoT applications.
In this application, our two sensors will be placed in one lane on a road. The magnetometer will produce a cosine wave-like signal as the car approaches the sensor. The inductance measured by the magnetometer increases as the car approaches the sensor. We can set a cutoff for the inductance value to specify when a car is “above” the sensor. We will set this cutoff to be the same for the sensor (say 5 meters) farther along the road. The time taken for the inductance to reach the same cutoff for both sensors will give us the time taken for the car to travel 5 meters, giving us both parameters necessary to calculate the speed of the car.