Conventional cellphone networks aren’t for everybody. In the state of Oaxaca, Mexico, rural communities high in the Sierra Juárez mountains have been building their own 2G cellular networks using mostly open-source and low-cost software and hardware. These communities have liberated themselves from dependence on large commercial networks that had neglected their sparsely populated region.
They can do this in part thanks to software able to take over functions that once required hardware and to a parallel movement to make such software open source and almost free. So-called software-defined radios make it easier for tinkerers and researchers to prototype their own components for a 4G LTE technology cellular network. While a full open-source version of 4G LTE is not yet complete, a proposed agreement between some academic and industrial partners would ensure that open versions in the works will be interoperable with commercial systems. Continue reading
There is no visible horizon in the waters beneath the Ross Ice Shelf. So electrical engineer Jim O’Sullivan built an artificial one for the pilot of the submersible remotely operated vehicle (ROV) that he and a team of scientists were testing there in 2008. The team didn’t lack for data: The ROV’s orientation, speed, and depth were numerically displayed on the pilot’s screen. But it is difficult to convert numbers into spatial awareness. The ROV was at risk of crashing into the delicate creatures, such as sea spiders, that it was supposed to be observing.
Fortunately, O’Sullivan had come across a similar problem in a different setting: aviation. As a pilot, he had an instrument rating, “which was useful for understanding how to navigate without being able to see,” he recalls. When flying blind, pilots use half a dozen different instruments to maintain their situational awareness, including an artificial horizon. O’Sullivan found open-source software that could convert the ROV’s telemetry data to display an artificial, underwater horizon. This example of engineering on (and under) “the Ice,”—as Antarctica is known—demonstrates the need for ingenuity and improvisation beyond anything training can provide. Continue reading
In late September, Volkswagen admitted to using software that activated hardware to scrub nitrogen oxide (NOx) emissions during required emissions tests, but not during normal driving. The deception improved the cars’ gas mileage at the cost of emitting between 10 and 40 times the legal limit of NOx, a precursor gas to nitrogen dioxide (NO2), ammonia (NH3), and other gases that cause respiratory problems. In the last few years, newly maturing instruments of several kinds have converged on a single message: diesel exhaust in the real world is far higher than what carmakers advertise and what is permitted by the law in many countries.