Facilities and equipment

Last changed: 02 June 2021

Sensola consists of a traditional laboratory in a controlled indoor environment, which supports an innovative set of portable equipment that is used for outdoor studies. The research is oriented towards environmental psychology and landscape architecture.

The indoor laboratory consists of two experimental rooms with equivalent properties and a control room. The experimental rooms feature equipment for audiovisual simulations of outdoor environments and the possibility to measure psychophysiological responses. Monitoring and analysis take place in the control room. Fully developed, the indoor laboratory will also support presentations of environments in Virtual Reality.

Laboratory

Indoor laboratory

 

 

To develop new and in-depth knowledge of how outdoor environments are experienced on site, smart and portable technology is used, which allows people to interact in a natural way with their surroundings. The equipment facilitates collection of location data (e.g. GPS, accelerometry and video) as well as physiological response (e.g. skin conductance, respiratory rate and heart rate). Consumer oriented technology such as heart rate monitors enable data collection on a larger scale. Different types of data can be synchronized, illustrated and analyzed in the physical laboratory indoors.

Painting of forrest

Outdoor laboratory

 

Examples of equipment

Bionomadix

A central system in the laboratory is Biopac’s Bionomadix combined with the software Acqknowledge. Biopac’s portable equipment is used to record physiological data in real time (e.g. respiratory rate, heart rate, heart rate variability and skin conductance). Data is then imported and synchronized in the Acqknowledge software for further analysis.

Eyetracking and VR

Eyetracking is a technology that makes it possible to understand how subjects interact with their environments visually, by registering eye movements (saccades), fixations and pupil size. Screen-based eyetracking is used for indoor studies, mobile eyetrackers for outdoor studies. Eyetracking can also be combined with Virtual Reality simulations, VR.

Site documentation

In the laboratory, there are different types of video cameras, both conventional variants, action cameras, spy glasses and smart phones. Action cameras have high resolution and good image stabilization, suitable for documentation of outdoor activities. Spy glasses look like ordinary glasses, but have a hidden video camera integrated in the frame. Modern smart phones have the ability to record video along with other data, such as accelerometry and GPS. They can also be used to synchronize data from external devices via Bluetooth.

Empatica E4

Empatica E4 is a portable, medical instrument that is worn like a watch. Empatica E4 has sensors that record skin conductance and blood volume pulse via a light sensor (PPG). The watch has an internal memory, but can also be connected via Bluetooth to, for example, a smart phone to illustrate data in real time. There are two Empatica E4 in the laboratory.

Polar H10

Polar H10 is a consumer-oriented chest strap typically used to measure heart rate during training. The Polar H10 can also record ECG, which can be used to provide information on both heart rate and heart rate variability. Sensola has four Polar H10s in two different sizes.

Facts:

Physiological concepts

Skin conductance

Skin conductance is one of the most established and reliable indicators to measure activation level (arousal). Skin conductance can also say something about stress, because increased activation in the sympathetic nervous system (fight or flight response) increases sweat secretion. The reverse relationship also applies, i.e. reduction in skin conductance (or return to baseline) indicates activity in the parasympathetic nervous system (the body's resting system). An increase in activation can have many explanations, hence skin conductance usually needs to be paired with other data.

Pulse

The working rate of the heart, the pulse, is correlated with level of physical activity, but also says something about the mental state, where a higher pulse can indicate stress and cognitive load.

Heart rate variability, HRV

Heart rate variability is a measure of the average time difference between heartbeats. Low heart rate variability is usually linked to activity in the sympathetic nervous system (stress), while a higher variation indicates the parasympathetic system (rest). It is possible to train HRV, which can lead to a better balance between the sympathetic and parasympathetic nervous systems and thereby also resistance to stress. Heart rate variability can be estimated via pulse (RR) and blood volume pulse (PPG), but the best accuracy is given by the ECG. Heart rate variability can be expressed as a standard deviation in R-R

PPG photoplethysmogram

A type of sensor based on short light pulses. The body's blood vessels absorb the light signals differently depending on blood volume and oxygen saturation. A PPG sensor sends several light pulses per second, and by measuring how much of the light that comes back, a graph of the blood volume pulse can be plotted.

 

Pulse oximetry

A type of PPG sensor that measures oxygen saturation in the blood. The sensor is usually placed on the finger or earlobe, diodes emit light in wavelengths that are absorbed differently depending on the degree of saturation of the blood.

ECG

Measurement of the heart's electronic activity over time. Can be used for detailed analysis of, for example, heart rate variability and heart rate.

Respiratory rate

There is a natural connection between the body's activity level and respiratory rate, in such a way that the respiratory rate decreases at rest. This relationship can also be double-acting.


Contact

Caroline Hägerhäll, professor
Department of People and Society
caroline.hagerhall@slu.se +46 40 41 50 15

Gunnar Cerwén, postdoc
Departement of people and society
gunnar.cerwen@slu.se, +46737182797

Page editor: marianne.persson@slu.se