Pixel International Conferences

Digital data acquisition in science lessons is a particular challenge in terms of availability and operation of the devices. Classical laboratory measuring instruments often focus on data acquisition, which is why the handling in the classroom varies greatly depending on the manufacturer and equipment. Access to complex measuring equipment such as spectrometers or polarimeters is further complicated by high costs. With the help of individual electronic components and various materials or in combination with a 3D printer, some of these measuring devices can be reproduced, which makes access in STEM-classes inexpensive [1-3]. At last, the measurement values are recorded by handwritten transmission and application of measured variables or the strength of acoustic signals, which on the one hand requires time and on the other hand can make joint evaluation difficult.
The LabPi software [4], which was specially developed for the Raspberry Pi single-board computer, offers an additional digital solution to this challenge. This software combines different measuring instruments to a uniform low-cost measuring station with the help of a multitude of miniature sensors. It is didactically tailored to teaching and thus offers a basis for supplementing previously analog processing steps with the aspect of digital data acquisition and evaluation.
The article presents the development of a low-cost polarimeter based on the Raspberry Pi and the software LabPi. The construction and the functionality of the digital polarimeter are described by means of simple components. In addition, the possibilities for digital evaluation and visualization of optically active substances are presented by means of selected comparative measurements.

Keywords: Measurement Systems, LabPi, Digitalization, STEM Education 4.0

References:

1. Bernd, P. & Mendez, J. D. (2020): Low-Cost 3D-Printed Polarimeter, J. Chem. Educ. 97/4, 1162-1166. DOI: 10.1021/acs.jchemed.9b01083
2. Elsholz, O., Rodrigues, T. C. (2005). Vom LED-Photometer zum Photosensor. GIT Labor-Fachzeitschrift 6/519-520.
3. Bee, U., Jansen, D. (2018). Der melodische Leitfähigkeitsprüfer - low cost mit großer Leistung. CHEMKON 25/1, 35–38.
4. M. Wejner & T. Wilke (2019): Low Cost – High Tech: The Digital Measurement System LabPi, CHEMKON, 7 (26). DOI: 10.1002/ckon.201900016