The VCM function is useful for users because they do not need to work with physical circuit components to learn designing and construction of electronic circuits. The VCM, proposed in a previous study (Takemura, 2013), enables individual learners to use graphics editors, which are installed on a learner’s computer.
Therefore, this system does not require the use of proprietary graphics software. To construct a virtual circuit of a line tracer, we improved the previous VCM by increasing the database of virtual circuit components, including a picture of Arduino. Figure 2 shows examples of virtual circuit components that are necessary to construct virtual circuits of line-tracer robots with the microcontroller Arduino. Each experimenter downloaded these virtual circuit components and a template circuit board (breadboard) image. Experimenters used their preferred graphics editor to indicate connections of circuit components on a virtual circuit by placing virtual circuit components on the circuit board image. The experimenters indicated the virtual circuit connections by drawing colored lines on the circuit board image using a graphical user interface