Good day everyone.
This question from a (medical) newbie (use simple words in short sentences, please):
I'm monitoring animals with lowering blood pressure and need to automatically start 110V infusion pumps to increase their blood pressure back to an acceptable level.
I have blood pressure transducers which output amplified analog voltages. These voltages are digitized and recorded by a computer. BEFORE digitalization, I'd like to route my analog signal through an ON-OFF voltage-sensing switch with a threshold. Upon crossing the adjustable threshold, the switch would switch to ON, starting the pump.
For instance, my "good pressure" voltage would be 3V (DC); when the animal's pressure reaches a voltage of 2.5V (DC), the switch would turn on to start the pump to infuse the animal and get its pressure back up beyond 2.5V, at which point the pump would stop.
In my dreams, there would be three (3) thresholds to start three pumps. At 2.5V, Pump #1 starts. If that is not enough and the animal's pressure keeps dropping, Pump #2 is started when the voltage hits 2V. A third threshold (1.5V) would start a third pump. Together, these would work to infuse the animal with an increasing volume of fluid, maintaining its pressure high enough.
I can picture the system, but don't know how to build it. I have the pumps, the sensors, and the amplifiers. But I am missing the ON-OFF switching watchamacallit that will be configured with the threshold to activate the pumps.
All ideas are welcome! As mentioned, I am not an electronics expert, just a cardiologist. I appreciate your help.
Dan
This question from a (medical) newbie (use simple words in short sentences, please):
I'm monitoring animals with lowering blood pressure and need to automatically start 110V infusion pumps to increase their blood pressure back to an acceptable level.
I have blood pressure transducers which output amplified analog voltages. These voltages are digitized and recorded by a computer. BEFORE digitalization, I'd like to route my analog signal through an ON-OFF voltage-sensing switch with a threshold. Upon crossing the adjustable threshold, the switch would switch to ON, starting the pump.
For instance, my "good pressure" voltage would be 3V (DC); when the animal's pressure reaches a voltage of 2.5V (DC), the switch would turn on to start the pump to infuse the animal and get its pressure back up beyond 2.5V, at which point the pump would stop.
In my dreams, there would be three (3) thresholds to start three pumps. At 2.5V, Pump #1 starts. If that is not enough and the animal's pressure keeps dropping, Pump #2 is started when the voltage hits 2V. A third threshold (1.5V) would start a third pump. Together, these would work to infuse the animal with an increasing volume of fluid, maintaining its pressure high enough.
I can picture the system, but don't know how to build it. I have the pumps, the sensors, and the amplifiers. But I am missing the ON-OFF switching watchamacallit that will be configured with the threshold to activate the pumps.
All ideas are welcome! As mentioned, I am not an electronics expert, just a cardiologist. I appreciate your help.
Dan