Posts with «radar» label

Enforce Speed Limits with a Rusty Bike

They say you can’t manage what you can’t measure, and that certainly held true in the case of this bicycle that was used to measure the speed of cars in one Belgian neighborhood. If we understand the translation from Dutch correctly, the police were not enforcing the speed limit despite complaints. As a solution, the local citizenry built a bicycle with a radar gun that collected data which was then used to convince the police to enforce the speed limit on this road.

The bike isn’t the functional part of this build, as it doesn’t seem to have been intended to move. Rather, it was chosen because it is inconspicuous (read: rusty and not valuable) and simply housed the radar unit and electronics in a rear luggage case. The radar was specially calibrated to have less than 1% error, and ran on a deep cycle lead acid battery for around eight days. Fitting it with an Arduino-compatible shield and running some software (provided on the github page) is enough to get it up and running.

This is an impressive feat of citizen activism to provide the local police with accurate data to change a problem in a neighborhood. Not only was the technology put to good use, but the social engineering involved with hiding expensive electronics in plain sight with a rusty bicycle is a step beyond what we might have thought of as well.

Thanks to [Jo_elektro] for the tip!

Arduino Radar Watches You Breathe

We’ve all likely watched an episode of “Star Trek” and admired the level of integration on the sick bay diagnostic bed. With its suite of wireless sensors and flat panel display, even the 1960s imagining of the future blows away the decidedly wired experience of a modern day ICU stay. But we may be getting closer to [Dr. McCoy]’s experience with this radar-based respiration detector.

[Øyvind]’s build, which takes the origin of the term “breadboard” to heart, is based on a not-inexpensive Xethru module, which appears to be purpose-built for detecting respiration. The extra-thick PC board seems to house the waveguides internally, which is a neat trick but might limit how the module can be deployed. The module requires both a USB interface and level shifter to interface the 2.8V levels of the module to the 5V Arduino Uno. In the video below, [Øyvind]’s prototype simply lights an RGB LED in response to the chest movement it detects, but there’s plenty of potential for development here. We’ve seen a laser-based baby breathing monitor before; perhaps this systems could be used to the same end without the risk of blinding your tyke. Or perhaps better diagnostics for sleep apnea patients than an intrusive night in a sleep study lab.

Clocking in at $750USD for the sensor board and USB interface, this build is not exactly for the faint of heart or the light of wallet. But as an off-the-shelf solution to a specific need that also has a fair bit of hacking potential, it may be just the thing for someone. Of course if radar is your thing, you might rather go big and build something that can see through walls.


Filed under: Arduino Hacks, Medical hacks

LEDs Turn This Paper Map into a Tram Tracker

Public transit can be a wonderful thing. It can also be annoying if the trains are running behind schedule. These days, many public transit systems are connected to the Internet. This means you can check if your train will be on time at any moment using a computer or smart phone. [Christoph] wanted to take this concept one step further for the Devlol hackerspace is Linz, Austria, so he built himself an electronic tracking system (Google translate).

[Christoph] started with a printed paper map of the train system. This was placed inside what began as an ordinary picture frame. Then, [Christoph] strung together a series of BulletPixel2 LEDs in parallel. The BulletPixel2 LEDs are 8mm tri-color LEDs that also contain a small controller chip. This allows them to be controlled serially using just one wire. It’s similar to having an RGB LED strip, minus the actual strip. [Christoph] used 50 LEDs when all was said and done. The LEDs were mounted into the photo frame along the three main train lines; red, green, and blue. The color of the LED obviously corresponds to the color of the train line.

The train location data is pulled from the Internet using a Raspberry Pi. The information must be pulled constantly in order to keep the map accurate and up to date. The Raspberry Pi then communicates with an Arduino Uno, which is used to actually control the string of LEDs. The electronics can all be hidden behind the photo frame, out of site. The final product is a slick “radar” for the local train system.


Filed under: Arduino Hacks, Raspberry Pi

The First Arduino Radar Shield

The very first fully operational radar Arduino shield was recently demonstrated at Bay area Maker Faire. It was built by [Daniel] and [David], both undergrads at UC Davis.

Many have talked about doing this, some have even prototyped pieces of it, but these undergrad college students pulled it off. This is the result from Prof. ‘Leo’ Liu’s full-semester senior design course based on the MIT Coffee Can radar short course, which has been going on for 2 years now. Next year this course will have 30 students, showing the world the interest and market-for project based learning. yet again showingWe  the influence of hackers on higher education.

Check out the high res ranging demo, where a wider band chirp was used to amazing results. Video below.


Filed under: Arduino Hacks, hardware

DIY Sonar for the Blind

This is one of those simple concepts which makes you think “Why didn’t I think of that?”  The entire sonar unit is attached to a wearable glove and as the user sweeps their arm back and forth, the device can detect anything from one inch to 10 feet in size.

Two servomotors apply pressure to the top of the hand when obstructions are detected. The closer the object is, the more pressure is applied. The response time is in milliseconds, allowing a blind person to navigate easily around obstacles or find items on a table, for example.

Top Sonar Projects

Hack n Mod 06 Oct 18:59
arduino  blind  radar  sensor  sonar