Cybersecurity typically protects digital devices from malicious software. But new research suggests devices such as smartphones, fitness trackers, and even autonomous vehicles could be vulnerable to hacking via sound waves.

Researchers at the University of Michigan found that by using specific acoustic tones they could trick the tiny sensors known as accelerometers—devices that measure the change of an object’s speed in three dimensions—into giving false readings.

With an inexpensive speaker, the researchers fooled a Fitbit fitness tracker into registering thousands of phony steps. They used a smartphone’s own speaker to play a music file containing malicious tones, which allowed them to hack into the phone’s accelerometer controlling a toy car.

Tricking the sensors into delivering false signals in these devices challenges basic assumptions about hardware security, the team told University of Michigan News.

“We trust our senses and we use them to make decisions,” said Timothy Trippel, a doctoral student in computer science and engineering and lead author of a forthcoming paper on the research. “If autonomous systems can’t trust their senses, then the security and reliability of those systems will fail.”

The Michigan researchers have proposed both hardware and software updates to defend against such acoustic vulnerabilities.

Sunshine potential

If you’ve ever considered solar power for your home but rejected the idea because you don’t live in Arizona (or some other sunny location), Google wants you to think again.

Project Sunroof, launched by Google in 2015 to help people answer the question, “Does solar power make sense on my rooftop?” now has data from every state, with approximately 60 million buildings analyzed. Leaving aside the question of solar power’s ability to outperform fossil fuels, Project Sunroof is revealing interesting data about the viability of solar energy on rooftops based on the total sunlight available to homes and businesses across the United States.

According to Project Sunroof, more than 90 percent of homes in Hawaii, Arizona, and New Mexico are technically viable for solar power. Sixty percent of homes in Pennsylvania, Maine, and Minnesota are viable. Nationwide, 79 percent of all rooftops analyzed have enough unshaded area for solar panels.

The city with the most solar potential: Houston, with enough sunlight to produce 18,940 gigawatt-hours per year—enough to power 1.7 million homes. —M.C.

Happy hauling

Truck drivers work odd hours, driving for long stretches at a time, including at night. For truckers in northern Europe, where Arctic winters mean even daytime hours are dark, the lack of light can affect both driving performance and mood.

Researchers at European truck manufacturer Daimler found that the shape of most truck cabs limits the amount of natural light that shines inside. They wanted to learn if adding artificial daylight to cabs would have a positive influence on drivers. At a site in Rovaniemi, Finland, test drivers simulated two weeks of winter driving—the first week driving in cabs equipped with conventional lighting and the second week in cabs fitted with a module that emits artificial sunlight with a concentration on the blue end of the spectrum.

In post-test interviews, the drivers reported their moods significantly improved when using the artificial daylight system, and onboard cab data showed their driving performance also improved.

According to Daimler, the drivers said that while using the artificial daylight, they found the space inside the cab to be more pleasant. —M.C.