At the beginning of the first day, after a warm up activity for the students to introduce themselves and feel at ease and after setting ground rules, a presentation of applications and the architecture of the Internet of Things was made using two videos. The first video was about everyday situations that the Internet of Things technology can contribute and support. The characteristics of the Internet of Things were described in the second video. Next, using the brainstorming technique we defined “smart environment” and how the process of collecting recyclable materials can be improved. In addition, on the first day, the umi-sci-ed.cti.gr platform was presented. A project for the summer school of Larissa was created on the platform. The first day of the summer school was ended with the presentation of the Udoo device and its features (processor, memory, operating systems, sensors, interfaces etc.) as well as the accompanying material such as breadboards, jumper wires, LEDs, switches, resistors, sensors etc.
The second day began with a guessing game for students to revise the main concepts of the previous day. They were divided in small groups. A volunteer from each group wore a hat. A word that corresponded to a concept presented the previous day was written on it. The other members of the group described the meaning of the word and the volunteer had to guess the word from clues given. Roles were switched. Following the game, the concepts of voltage and current were introduced. Students measured battery voltage and resistor values using multimeters. The Ohm’s law was presented and examples were discussed. Circuits were constructed using breadboards, batteries, resistors, switches, cables and light-emitting diodes. Then the operation modes of Udoo were described: Headless IoT Device, Lightweight Desktop PC and Arduino. The interaction with the use of built-in sensors (gyroscope, accelerometer and magnetometer) was examined. After that the students were introduced to the Arduino programming environment and code writing with examples from the Web Control Panel of Udoo. The code of the first example was modified in order to activate a light-emitting diode on a different output pin and the corresponding electronic circuit was implemented.
The use of ultrasonic waves was introduced for distance measurement. The operation of an ultrasonic sensor was discussed. An electronic circuit was implemented to measure distance using Udoo and ultrasonic sensor. The Arduino code used for this purpose was presented in detail and discussed. Students used rulers to verify the results.
The third day began with the same guessing game the students had played the previous day. Then a discussion about the problems of collecting recyclable materials in recycling bins was held. The development of an application aimed at improving the collection process was examined. A small bucket was selected. Students using a ruler found its dimensions (base circle radius and height) and then they calculated its volume. An ultrasonic sensor was fitted at the top of the bucket in order to estimate the height of the recyclable materials and their volume. The students implemented an electronic circuit to measure the height and volume of the recyclable materials using the Udoo device, a raster, jumper-wires, a green led, a red led and an ultrasonic sensor. When the green led turned on meant that the level of recyclable materials was below a predetermined low level. When the red led turned on meant that the level of recyclable materials was above a predetermined high level. Then the students were given an incomplete Arduino code for measuring distance, calculating sizes and activating leds. They engaged in a dialogue and in order to complete the code they used the previous example of the Arduino code for distance measurement. The next step was the transfer and display of cloud measurements through the ThingSpeak platform and then on the smartphone via the Widget IoT Thingspeak Monitor and the ThingviewFree application. The last step was sending a notice about changing the level of recyclable materials through twitter.