Researching Sensors
(Backdated: Oct. 18, 2016)
We’re just getting started, and I have made it my mission to hash out what our software system would look like. I want to make it easy for whoever was using our system to understand exactly what is going on at all times. For instance, if the system starts to overheat, I want the user to be alerted of that. I also assume that we’ll need to monitor our melted PLA in order to ensure that when it’s extruded, it will be viable for printing. With both of these things in mind, I’ve started researching sensors that would be useful to us.
Thermal sensors are clearly a must, and I determined fairly quickly that I want us to use them for two purposes: 1) to determine how hot the system is; and 2) to assess how evenly distributed the heat is throughout the extrusion barrel. I also started looking into visual sensors that will allow us to determine the homogeneity of our melted PLA. Air bubbles can compromise the usability of filament, so we want to reduce the probability of air bubbles appearing as much as we can. My thought is that if the melted plastic has air bubbles in it while still in the barrel, we can sense that and tell the system to continue mixing (rather than extruding while there are still bubbles present). While trying to figure out how exactly this system will work, I sketched a block diagram of the software functionality for our heating system.
Researching methods of homogeneity sensing has yielded very little. The most viable option I found involves using lasers, so I figure we’ll have to design our sensing system ourselves. That’s fine; IR sensors are useful and we’ve all had some experience working with them already. I don’t know how we’ll mount them, but they could potentially comprise an effective sensing system.
