The African School of Fundamental Physics

Introduction

Courses on experimental physics are very scarce in Africa. When talking to African professors, I always hear that the reason is missing funds. With this course, I want to prove the contrary.

Many, if not most, physics experiments today involve

• some kinds of sensors
• electronics to convert the sensor signals into something a computer can read
• actuators allowing to control the experiments
• an acquisition and control program
• networks interconnecting the computers
• computers analyzing the data and displaying them in graphical from

The equipment

In order to demonstrate how such an experiment is set up, we had for the 2022 edition of the African School of Physics:

• a microcontroller (CPU) with interfaces allowing to access sensors and actuators
• the microcontroller has a Bluetooth adapter and a Wi-Fi interface for network access
• a simple push button switch simulating a sensor that creates a binary signal. A real sensor might be a reed relay triggering when a magnetic field is close by or a thermistor triggering when a certain temperature level is exceeded ...
• a user programmable LED is available on the CPU card. This can be used as an alarm signal
• a 7 rgb LED chain used as a simple display device
• a linear potentiometer simulating sensors which deliver analogue signals. A 12 bit analogue to digital converter (ADC) as well as a 8bit a digital to analogue converter (DAC) are available on the CPU card.

• SHT30 temperature and humidity sensor
• BMP180 temperature and barometric pressure sensor
• SSD1306 monochrome OLED display with a resultion of 128x64 pixels
• stepping motor with driver

The cost of a complete 2022 set as described above is ~ 13 US $, shipping and VAT included. You can easily use the devices for 5 years, which will bring down the price per student and year to 3 US $. For a full school or university course you would add real sensors (e.g. temperature and humidity sensor, atmospheric pressure sensor, ultrasonic distance sensor, movement sensors ...) as well as real actuators like relays, motors ... which may bring up the cost to ~ 50 US $. Distributed over 5 years, this comes down to 10 US $ per student and year, which is still very reasonable.

The problem: How do we use such a system?

... and this is what these pages are all about.

The course or let's call it workshop consists of some minimal lectures and a maximum number of hands-on exercises. You will get exercise sheets and the solutions will also be available to you for download. This will allow you to compare my version to yours.

-- Uli Raich - 2022-10-14

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