Karl St-Arnaud's Arduino-Compatible Journey Tracker Aims to Map Road Quality as You Drive
Mounted in car's cup holder, this gadget tracks vibrations through an IMU to classify road quality.
Engineer Karl St-Arnaud has built a device designed to provide a qualitative analysis of the roads on his cycle journeys — by tracking the bouncing of an inertial measurement unit (IMU) and visualizing the data on a map.
"I live in Montreal Quebec and I love cycling," St-Arnaud explains. "I had the chance to ride in different places around the world and let's just say our roads are not bad here, they are terrible. Recently, I was thinking wouldn't be nice if there was a way to know the road condition before riding on it; you know like you have a traffic estimate on most navigation applications these days which guide your journey. Traffic prediction is achieved by monitoring the GPS location and speed of all the users that are on the road. Could we use a sensor that is massively available to achieve the same type of estimation but for road quality?"
That "massively available" sensor: An inertial measurement unit (IMU), or at least the accelerometer portion thereof, as found in all major smartphones and tablets. Using this, St-Arnaud presumed, it would be possible to track vibrations during a journey — data which could be used to surmise road quality, with a rougher road creating corresponding spikes in the measurements.
"When I start a project, I like to do a first quick iteration to estimate if my idea have potential to succeed," St-Arnaud continues. "The goal of this first iteration is not to go too deep in the detail of the implementation, but more to estimate the potential and feasibility of the project. For this first version, I designed a first proof of concept and tested it with a road test."
The proof-of-concept prototype is based around an Arduino Nano compatible microcontroller board with a Waveshare WAVE-100 inertial measurement unit, based around the TDK InvenSense MPU-9255 with three-axis gyroscope, three-access magnetometer, and three-axis accelerometer. A custom mount allows the gadget to be placed inside a cup holder in St-Arnaud's car, while a smartphone's GPS is used to track exactly where the journey takes place.
"[A map was created] showing the processed acceleration data overlay on top of the GPS data," St-Arnaud writes of the successful experiment. "Green colour showing part of the road where the road quality metric was good and red the part were it was particularly bad. During the ride, I identified two main areas where the road was particularly bad and one area where the road was good."
With the concept proven, St-Arnaud is now working on an upgraded design with integrated GPS capabilities and a higher resolution. The project's progress can be followed on St-Arnaud's Hackaday.io page.