LabPi

Information on Construction, Analysis and Connectivity of LabPi.

Construction

The fundamental goal of LabPi is to supplement the low-cost range with a variety of digital acquisition and evaluation methods. Instead of isolated solutions for each measurand, an open and adaptable platform was developed to which various sensors can be connected as required. The LabPi measuring station thus offers new experimental possibilities for use in schools, student laboratories and universities and does not require any programming work or in-depth technical knowledge.

LabPi combines suitable minicomputers with powerful (miniature) sensors. The modular design allows numerous measured values such as pH, conductivity, pressure, temperature, etc. to be recorded individually or in combination. The cumstom developed adapter board allows them to be connected and changed as easily as USB sticks. The use of low-cost components also reduces instrument costs to the point where the purchase of several stations - or even a class set - becomes realistic for schools and student labs. LabPi can already be used to record numerous measured variables in STEM classes (blue). Further sensors are currently being developed (yellow).


Analysis

Two key success factors determine the success of digital tools in the classroom: a high level of usefulness and ease of use by teachers and learners.

To ensure both factors, we have designed and developed the LabPi software. With this independent program, necessary processes (recognition of the sensors, integration of the drivers, etc.) are automated in the background, so that LabPi can be operated intuitively without long familiarization. In the foreground, however, is the graphical program interface, with which measured values of each sensor can be easily recorded, displayed in tabular and graphical form, evaluated, saved and exported to common formats. The measured values are thus recorded with just a few mouse clicks or fingertips.

In principle, the user interface has a uniform structure, which is slightly supplemented by specific measurement options for each measured variable. In terms of teaching, this design offers the advantage that the operation of the software and the handling of the measuring station only have to be learned once and can then be transferred to other measured variables. Instead of repeated familiarization phases for each new measuring instrument, the focus is thus shifted to the application phase, which means that more effective learning time is available for experiment and evaluation. If LabPi is also used in other subjects (e.g. biology, physics), the synergy effects are further enhanced.

For the analysis the determined measured quantities are displayed simultaneously in tabular and graphical form by LabPi. In addition, mean values, compensation lines and slopes can be displayed, depending on the requirements also as a function. The display of multiple representations leads to a deeper understanding of the learning contents in studies; furthermore, the frequent handling of corresponding representations usually also strengthens the understanding of concepts. If there is interest in more in-depth evaluation options or if the data is to be saved for later evaluation, it can either be stored on the device or exported to a USB stick or to the Internet platform for all common spreadsheet programs.

Connectivity

LabPi measuring stations can be networked via WLAN with the associated cloud platform COMPare - this offers innovative teaching-learning opportunities for STEM lessons.

A practical example is the joint evaluation, discussion and assessment of experimental results. Typically, after the laboratory work, the results or measured values of the working groups are collected on the blackboard or drawn diagrams are discussed in the square, which is either at the expense of time or overview. LabPi can make this more efficient by networking several measuring stations. When the connection is established, measured values of all groups can be merged via the associated cloud platform COMPare.This enhances the content of the evaluation phase and makes it more efficient in terms of time.

For the students, a comparative evaluation of all group results becomes possible. This enables them to critically scrutinize their own experimental results in direct exchange with other groups and the teachers, and thus also to independently identify errors in the experimental procedure. In addition, the results can not only be saved locally on the device, but also in the cloud in the long term if required. In this way, this data can also be retrieved later for other groups and used further.

Best-Practice example: COMPare

You can view a demonstration of the free COMPare cloud platform here: LabPi COMPare.