The whole event has been accommodating allowing both myself and fellow VRU technologists the opportunity to host a couple of arts based talks as well as involvement in workshops. One of which incorporated physical computing with programming. This has been invaluable because it has firmed by knowledge of microcontrollers and how to make use of sensors to control other devices.
I've picked up valuable knowledge about the amplification and signal conditioning aspects of my biofeedback project. I know know that i seriously need to take thermal noise into account when choosing resistive components as well as carefully positioning the precision analog Op amps. In terms of BVP (blood volume pulse) information I think i will only need a x10 gain to move a 10mV-200mV signal to something a little more noticeable to the Arduino analog inputs. These have a 5/1023 (v) resolution. Also from what i have noticed the Nexus-4 does not amplify analog sensors (except for unity gain reinforcement) after the sensor stage. This is interesting.
For now, the next step for me is to power the sensors (if needed, some are passive) and measure what signal i get from them, and work out the most effective amplification stage (as little and noise free as possible). I'm hoping for a respiratory and BVP measurement that this gain will not need to be an awful lot.
Asides from the electronics side I've done a lot into the visualisation side of things. This is effectively the visual feedback element and involves manipulating playback speeds and colour saturation of a heartbeat video. I will upload a quick example at some point in the next few days.
Tiring week but fully enriching.
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