There are so many cool things you can make with mini radar circuits. I thought I’d share some examples from my time in the radar business. Then end with a few examples of where you can get a hold of a radar circuit.
Just to be clear: A radar is a sensor that uses electromagnetic waves for sensing. This is NOT ultra-sound. This is the real deal.
In 2009, Elias Bakken and I founded the company Intelligent Agent to design touchless user interfaces using small radar circuits. Below is a video of the first prototype we made.
It was pretty cool to use advanced Ultra-wideband radar technology to do such a simple task as skipping through Powerpoint slides. The quality and sound are pretty bad (and it is in Norwegian), but as you can see I was pretty proud that night =)
Even though it was fun to make touchless interfaces, the price tag of the radar circuit was waaaay too high to justify the advantages compared to touchless interfaces based on ultrasound. So we ditched the touchless user interface idea eventually.
Non-contact Breathing Sensor
From then on we tried lots of different ideas. Here is a breathing sensor that can measure your breath without contact. Turn up the sound to hear me breathing and see how accurate it is!
But maybe the coolest example is when we use the radar circuit to see through walls! When we posted the following video in the end of 2011, it went viral and we got more than 40000 views in a few weeks!
This is how it works:
The radar sensor uses an Ultra-Wideband (UWB) chip from Novelda (www.novelda.no). It sends out electromagnetic pulses and analyzes the pulses that are reflected back. In the video above, a part of the electromagnetic pulse will be reflected back when it hits the wall and a part of it penetrates the wall and is reflected from the cabinet behind the wall.
Since the reflection from the cabinet will take longer to receive than the reflection from the wall, we can distinguish these two. In the example above, the robot is programmed to always keep a distance of 2 meters away from the cabinet. Therefore, you see the robot move in accordance to the movement of the cabinet behind the wall.
Arduino Radar: Fading an LED With my Breath
This is a project I did, to test if I could get the new XeThru radar to work with Arduino.
Check out the full Arduino Radar tutorial.
Where to get a radar circuit?
The radar sensors that you can actually do cool stuff with are, at the time of writing (2014), still a bit pricey for the hobbyist. But here are a few links to some companies that sell radar circuits:
Or you can build your own radar circuit.