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Motion Sensors for a Motion Product

Wearables are the next big thing. In fact in only the last few years there have been over 300 different wearable devices that have launched. Whether it's control, augmented reality, or anything in between, there's a use case for almost anything nowadays. The one thing they all have in common:the inclusion of a motion sensor.

 

Motion recognition has become an important value add to each device: From personal activity states to specific control from defined movements. Each motion device contains at minimum an accelerometer, this measures acceleration from any point (e.g. your wrist).

 

Other motion sensors have been added since inception, including: the gyroscope (measuring angular velocity), magnetometer (compass heading), and barometer (elevation). Each of these motion sensors have a unique value add and different sensor companies excel in each.

 

Motion Sensor Types: Accelerometer, Gyroscope, Magnetometer, and Barometer

 

One of the most important considerations when building a strong motion product is determining what type of motions you want to capture. The sensors you choose to use should reflect the individual motion.

 

Accelerate your product with accelerometers 

So what is an accelerometer? It's simply a sensor that measures acceleration in a direction from a point. They have the lowest battery consumption from all the available options. If you can get away with using just an accelerometer, this will allow you to build a motion product with a long battery life.

 

The challenge with these sensors is the resolution: more complex motions such as stick movements require additional information to ensure proper movements can be isolated and identified.

 

Accelerometer sensor data gifThis is an example of how sensor data is perceived by devices and software 

 

Don't get twisted about gyroscopes

A gyroscope allows for the devices rotation to be captured. A great example of this is capturing a bicep curl or any throwing motion, such as a lacrosse throw.

 

The challenge with these sensors are they are very power hungry. The trade off is having an equally powerful sensor which can allow for rotation and device orientation to be established.

 

Lacrosse throw gyroscope The rotation of a lacrosse stick can be captured with a gyroscope

 

Achieve alignment with magnetometers

What are magnetometers? They have the capacity to determine device heading and read magnetic fields for determining proximity or angle. A great example would be determing throwing angle. If you're looking to perfect your basketball shot, this may be the right sensor for you.

 

Don't sweat it with a barometer

Barometer captures pressure change in the atmosphere as you move, this gives a good approximation for height from a base known level. It allows for floors to be determined or even the height of a jump.

 

With any of these four motion sensors, you'll be able to integrate motion recognition into your product in no time! Stay tuned for next week where we'll show you the power of combining multiple sensors! Be sure to subscribe to our blog to be the first to read it!



John David Chibuk

Toronto, Canada | http://kiwi.ai

Entrepreneur in machine learning and sensor based software development (>10 years). Background in engineering, tech with professional experience in North America and Europe.