This device allows to measure Stress objectively . It is used in heart clinics.

This device is 26 000 USD in the Dr. Toys Store:

Schiller CS-200 Excellence Stress System with Treadmill

With the components listed on my site, we are able to build such a device for a view thousand dollars.

Buy for instance a curved treadmill such as the ADVG Curved Treadmill from U.K for 3 123 USD:

And add a 3 channel Gold Standard ECG device with spirometer to it which can be built from these components for less than 1 000 USD:

The AD8232 ECG chip, the ADS1115 16 bit A/D converter & an Arduino microcontroller – the building blocks for a multi-channel ECG device for medical & research grade applications

These devices are too expensive for my application which is meditation. But I am interested in using these devices and building such devices as open source alternatives, most probably as a lifetime journey.

With the components wich are currently available I esitmate that it is possible to build such an open source alternative for less than 5 000 USD.