3 Distributed Home Labs at the Time of the Covid 23 3.3 The New Revolution Offered by Microelectronics Although the “Flying lab” was an important step forward, still it did not solve some main issues, among the others the availability of sensors for all students, to get directly in touch with measurement problems. Moreover, Academia should train students to use what they will more easily use in their everyday life: the huge spread of the new low-cost MEMS sensors created a revolution not just in industry, as a reflection also on the new educational labs. At the same time, as sensors can be used by everybody, an enormous effort was made to increase awareness about metrology and its rules, to get good measurements: the new sensor performances had to be fully known to allow for the right choice in every application. New problems were behind the corner, as the reduced cost of each sensor modifies the general strategy in measurements; the new sensors have lower performances but allow denser networks; information redundancy becomes a main requirement, adding new issues related to networks of sensors, a topic seldom faced in measurement courses. The new systems come out equipped with microcontrollers: although their use is not complex, all the same the very short time allowed inside courses, especially in mechanical engineering, does not allow to learn even the basic and simple rules needed to start with their use. The first attempt was therefore to use analog output sensors, coupled to the already available boards, providing the power supply from the USB computer ports, to further push on the development of the “Flying Lab,” therefore making it richer and more autonomous. The set of available MEMS sensors is quite rich, as pressure, temperature, acceleration, sound, rotation, rotation speed, and many others can be measured, the main drawback consisting in the rather brittle connection between the sensors, often hosted on naked boards, and the data acquisition unit. The two most commonly adopted solutions have been Arduino [11] and STM32 [12] by STMicroelectronics, both having wide suites of already developed basic programs to perform the easiest tasks [13]. Students have also been invited to develop projects on own, and this served to develop awareness about the most common problems in experimental activities. A continuous interaction with developers has pointed out how the main problem for non-electronic engineers, using such devices, is the lack of a user friendly interface. Hence, a huge effort was made in helping to get over the barrier constituted by the needed software and hardware skills; this was recognized as a problem not only for education, but also for industrial applications. This is the reason why some products came out recently, with specific aids aimed at allowing everybody to use them. A line of products developed by STMicroelectronics for IoT has helped a lot also in education: the SensorTile.box [14] first, then the brand new STWIN [15] have been considered quite interesting. In the case of STWIN, a single board, created with the aim to prototype new measurement systems, without designing ad hoc boards, hosts many different sensors, a microcontroller, a wireless connection, a USB port, a Bluetooth antenna, and a slot for a micro-SD board; power to the system is provided by a small lithium battery, and some AI tools are already available on board. The burdensome task of microcontroller programming can be jumped over, as a simple smartphone app allows one to select the sensors to be used, the data rate, the storage output destination. Once the acquisition is over, data can be read back, thanks to a library developed in the most common programming languages for further evaluation. Though very powerful, some issues are still related to costs, not yet allowing to provide a board to each student, especially for crowded courses, unless a specific budget is provided. All the same this approach is still considered really powerful, as new MEMS sensors are available almost every day, making the available database richer and richer. This was the teaching standard we were working on, in our group, until February 2020. 3.4 The Smartphone: A Complete Measurement Lab Parallel to the described progress, the same MEMS sensors gained a lot of attention, being essential tools in every smartphone: smartphones are complete and rich labs, equipped with a number of sensors measuring a lot of different quantities. During February 2020, all educational activities had a sudden stop due to the pandemic. At a first glance, the impact over laboratory activities was feared to be a disaster, as both students and instructors were working at home. Many solutions have been tried to overcome these difficulties [16, 17]. A first attempt to heal this trouble consisted in trying to move at least some lab activities at home. Paired to this, there was a long-lasting experience in managing the students’ psychological approach to experimental activities: since the start of the experimental projects in the early 1990s, a clear need was recognized to force each individual to directly interact with hardware and instrumentation: some students, less familiar with practical issues, tend to refuse this activity; written reports
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