In Need of Heat Stroke Monitor Description?

"...heat stroke monitor ..."

Like a thermometer? This site recommends "Place a flexible indwelling thermistor rectally" for constant monitoring. Sorry, I cannot find a suitable image.

According to the wiki, heat stroke is defined by a body temperature over 40.6 C.

Body temperature in heat stroke can rise quite suddenly, over a period of minutes. So for your purpose the design might look at rhe rate of temperature change as well as the absolute temperature of the subject at a given moment.

Working principle could be simply defined as a software component which reads data from a sensor component, logs the temperature of the patient, performs simple math to calculate the rate of temperature change over time, and sends a message to activate an alarm component when certain criteria are indicating heat stroke is imminent (temperature approaching 40 C, or rapid temperature rise in the 37-39 C range, for example).

There are a lot of systems available for temperature monitoring - the sensor for starters is an important design variable. This system is designed to monitor exertional heat stroke with a probe type sensor. It logs temperatures but does not bother with the rate of temperature change.

Another system here uses a wireless ingestible sensor. Minimally invasive, I will hope that the sensor is very cheap, so no one will be tempted to re-use it.

One design feature I would include for a heat stroke monitor is to design for the earliest possible sign of heat stroke to trigger an alarm that can't be missed - both audible and visual alarm are best included. This would give you the most time to respond and avoid the risk of physiological damages.