Sensor Devices

Physiological grab- and wearable wired and wireless sensors.

One part of the SUM project took the direction of affective computing of physiological measurements in order to strengthen the link between music analysis and emotional feedback. The SUM bio-handle is the device we design and build for conducting our tests and experiments.

Prototype 1

Prototype 1

sensors: BVP and GSR
time: fall 2008

The first design was mainly to find the proper way to do the electronics for blood volume pressure (BVP) and galvanic skin response (GSR) sensors, as well as an easy way to pass the data for further processing. Most of the work was done by Bruno Herbelin.

Prototype 2a

Prototype 2a

sensors: BVP, GSR sensors and 3D gesture (3 axis accelerometer)
time: winter 2008

The second device was developed for our first experimentations. It uses the BVP and GSR sensors from the first version. Instead of the LabJack D/A converter we used the CUI board. The board was placed into a temporary cylindrical shape to test its functionalities (figure above).

A 3D gesture sensor was added in part to test how much physical movement would affect BVP measurements, but also as a motion sensor to process expressiveness in the gestures.

Data recording application for SUM bio-handle (Linux verison)

The CUI board was chosen for its ease of communication with computer programs on various platform. A Max MSP patch was made for OSX (Mac) and a Linux HID driver was developed (PC).

Some observations were carried through April 2009 at Aalborg University Copenhagen. Check the Preliminary Study Protocol document to know more about how the experiment was conducted, and read the Preliminary Study Conclusions to have more details on the lessons learned.

Prototype 2b

Prototype 2b

sensors: BVP, GSR, 3D gesture and  force sensor
time: spring 2009

This device was added a force sensor and fitted into a casing made on a 3D printer at Oslo University. The 3D casing design and print was done by Ståle Skogstad. Compared to prototype 2.a, the BVP is now measured on the thumb, the GSR on two major and ring fingers, and the pressure on the index. Read the Prototype 2a specification document for more details.

The force sensor was added to measure the strength with which the person holds the handle; this may be an indicator of stress, tension or attention shifts.

The device was used in the installation Versus by Bruno Herbelin and Lars Graugaard, presented at re-new 2009. The installation consists in an interactive bio-feedback presentation of horror movies, where the subject holding the SUM bio-handle controls the flow of pictures and the audio-visual effects through her/his physiological states (mainly hart-rate and GSR).

NB: a 2.c version of the prototype was made to test a better casing design (thinner and more ergonomic) but with no feature change.

Prototypes 2a to 2c of the SUM bio-handle

Prototype 3

sensors: BVP and GSR; 3D gesture; force sensor; audio sensor
time: spring 2010

Observations made on prototype 2  motivated some design changes; the GSR shouldn’t be measured on two close fingers (rather on two distant points, e.g. palm extremities), the pressure should be global to the full hand (otherwise we just have a button). Also the shape should be symmetrical for right or left-handed users.

The version 3 will take these comments into account.