Need to regulate wattage based on resistance of an exchangeable part.
I'll be putting different attachments ont he end of this device that will have different resistance between 3-4ohm down to around 1.0ohm. I need the device to read the resistance and adjust the voltage coming from the DC battery to match the wattage I set. Basically if I set it to 10watts I want it to always be 10watts no matter what resistance attachement is on it. I hope that makes sense. I'm sure there's a pre-existing board made by some one out there that does this or that could be salvaged from another device but I can't find one.
I know how to do variable voltage with a regulator but I need an auto sensing system where you set the output wattage. That goes a little beyond my expertise. Any help would be greatly appreciated, thanks in advance.