What is it controlling and What devices are in the loop
Dunno. Do you?
Sure. My thermostat controls the central heater and the central air conditioner. The thermostat in the refrigerator does the same thing for the refrigerator/freezer. The thermostat on the oven controls the oven heating element.
My physical body. Signals from many sensors travel over nerve fibres to a computer based on a neural network in my spine and head. That sends signals back down nerves to control muscles. The sensors monitor the position of my body by touch, by proprioceptors in my joints, by gyro-rate sensors in my ears and with a binocular 3D visual processor. It's not all working so well these days.
When the sensors disagree I feel nauseous due to the seemingly irreconcilable situation. This is good since my different sensors are effected differently by the possible toxins in my diet. When I eat something toxic, it confuses the system, I feel nauseous, then vomit, which reduces the poisoning, so my body survives, to injest more poison.
What is the context and background for your question, Jim? Is this for schoolwork?
Separate names with a comma.