Breaking out of enclosure problems. Surendra explains, “One of our earliest problems was that we were unable to fit the sensing system to properly measure pressure in a feasible way. We could get it in, through a laborious process, but it would not make sense to do it from a customer standpoint or even allow us to do a proper demonstration. So while we were trying to figure this out, one of our sensor vendor’s chief research and development person invited me over and showed the facilities that they have. It was during this tour that I discovered the kind of test setup we actually needed to build the product we had in mind.”
Another problem that they had was that the enclosure was built out of aluminium. Now, aluminium has this problem that it absorbs all signals due to it acting like a Faraday’s cage. When they placed the sensor inside it, no signals could make their way out of the device. “The team was very disappointed when this happened,” says Surendra. “While we were trying to figure out how to solve this problem, we came upon a material that had the characteristics of ABS plastic and did not absorb the signals that our device needed to transmit.”
The omnipresent battery life problem. Battery life is another area where they did some tuning and revisions to come up with the perfect sauce. For instance, they designed a range extender in the device that has the consequence of reducing battery life. So what they did was modify the device so that it only activates the extender when it is really needed, like in the case of a puncture where the car needs to alert the user as early as possible.
Another event that deactivates the range extender is when the car is moving. So they used the accelerometer to figure out if the car was moving and deactivate it if it was. It also changes the frequency of testing depending on different times of the day or usage history. They eventually left the range extender out of the first version of the product to control cost, but there is a good chance that it would show up in a future version.
“Testing is one area where I am facing a challenge. Normal tyres can only handle up to 50psi of pressure, but I needed to test the sensor at 150psi to make sure it works in heavy-duty tyres. I also needed to test the sensors while running at 10,000rpm. So what I did was to get access to a dynamometer; it was pretty expensive in our case since we need to constantly try and improve the system. We are now trying to set up a custom jig to get this done. We might go for a gyroscope instead of an accelerometer for suspension and wheel-alignment issues in a future product,” explains Surendra.
Dilin Anand is a senior assistant editor at EFY. He is B.Tech from University of Calicut, currently pursuing MBA from Christ University, Bengaluru