Images Scientific Instruments Inc. sitemap

Stretch Sensor Projects

Alternative Human Input Device Project

Project courtsey of: Paul Strohmeier
School: University College Maastricht

About the ShadowCoat

What am I building?

I am creating a wearable input tool. The main component is elastic conductive polymer, which changes its resistance depending on the amount of stretch it is subject to. In other words: low cost, plastic stretch sensors. These are used to measure the angle and rotation of head and arms in relationship to the body. The multiple measurements are read by an ATmega1280 microcontroller. The ATmega can connect to a computer via USB or can be used as the actual computing device.

The ShadowCoat is worn by its user and thus copies every move the user makes. These movements are used as implicit inputs to computing devices. The concept is very similar to motion capture devices such as commonly used for cinematic effects or movie animations. There are however very important differences, which I will explain in brief.

The ShadowCoat works independently of its environment.

The ShadowCoat does not require an external frame of reference, which means you are independent of external hardware and can leave the room whenever you feel like it. The ShadowCoat can be used in an elevator, car or plane You could even use it on the craziest rides in Disneyland if you wished, as it is independent of inertial forces.

The ShadowCoat is smart and simple.

The sensors do not require any complex software to interpret the readings. In fact, all calculating required is done by the suit itself. This enables real-time interaction even with computers, which can only offer very limited processing power.

The ShadowCoat is inconspicuous and non-intrusive.

The mechanical and electrical components required for the ShadowCoat interface are extremely lightweight. This enables mounting them in everyday clothing. The ShadowCoat can be worn underneath heavy winter clothing or as a summer t-shirt.

I experimented with rotational sensors, flex sensors and inertial sensors before finally settling on the stretch sensors as the main component. This is mainly due to the fact that I want to incorporate this technology in everyday clothing, such as long sleeved t-shirts. Rotational and flex sensors are not as easily compatible with the clothing commonly worn today.

Videos of the Construction Stage
Motion Capture of Wrist using Stretch Sensor and Arduino
Hand Motion Capure using Arduino and Images Bi-Flex Sensor

For more information visit the user's blog, found here: