You may have been wondering what is firmware; it is the part of the AFM that sits between the software interface and the electronics that control the microscope. This means that we need to take care of two tasks: first, to listen to the interface and translate that into a signal that controls the scanning stage. Secondly, we need to measure the signal from the AFM and send it back to the interface. These tasks are accomplished using an Arduino and a microcontroller that we can program to read & write voltages. To do all these things at the right time and in the right order, we control the behaviour of the Arduino using C++ code, we wrote this over the past two weeks. Continue reading Firmware – Update
It has been a while since the last electronics update when we had first got the focus error signal out. All the circuits now work together and are getting developed.
After talking to our “mechanics consultant”, Tom, we decided to redesign the stage and the stage holder so that we could use the dvd head holder that comes with the dvd head. It has some nice features that we could take advantage of, such as a cog system which could be used for coarse movement of the dvd head over the sample, and screw holes that we could fit the precision screws into. This means we don¹t need to have such a complicated design, with the old dvd head and flexure stage abandoned. Continue reading Mechanics – Update Four
Air pollution has become one of the major problem of many cities, affecting billions of people around the globe. Among all the noxious pollutants in air, fine particles with a diameter of 2.5 micrometers or less (Particular Matter(PM) 2.5) are the most harmful for human health because they are small enough to penetrate the lung, leading to premature death from heart and lung disease. PM2.5 particles come from activities that burn fossil fuels, such as traffic, which are abundant in urban areas. Continue reading Measuring Air Pollution