Abstract:

The science education without practical activities is nonsense. The experiments performed in laboratories have the role of motivating learning, developing technical skills and mainly fixing and facilitating theoretical knowledge.

The avalanche of new technologies and scientific discoveries force the educational system to keep up and also keep the pace. From the practical activities point of view the challenge is to upgrade the technologies used in laboratories but also to introduce new laboratories in the curricula. This can be an issue of economical significance, also implying aspects of space and qualified personnel. The Information and Communication Technologies changed and still change the teaching – learning processes. Computer simulations, virtual reality, computer games or remote laboratories make practical activities more interactive and attractive for students.

Nowadays a large number of hands-on experiments are conducted by computers. Even if the students are working in the classroom, the apparatus and instruments are still controlled by the computers. Taking this into consideration, the idea of remote laboratories implementation became a possibility, a necessity and today a reality. Based on web interfaces and web services, real apparatus and instruments can be remotely controlled by the students. In order to have the feeling of immersion as much as possible the same as in the case of hands-on laboratories, video streaming of the laboratories can be used as feedback. This can be achieved using web cameras.
In this paper the implementation of a remote laboratory based on LabVIEW web services is described. The laboratory works are dedicated to the analog electronics and physics fields.

The LabVIEW programming language is used for controlling the measurement and signal generation apparatus for electronic circuit study, for calling PSPICE simulation models and also for creating web services. The LabVIEW web services offer the possibility to access and control the apparatus through web. The client (student) web interfaces are built based on web programming techniques: html, java script, css, php.

From the hardware point of view the paper presents the new concept of “multitasking hardware” which allows more clients to be connected to the same experiment. We used NI myRIO board for performing the experiments. The myRIO board contains a real time processor and a FPGA which can be programmed directly with LabVIEW. These facilities allow controlling the access to the resources based on pipelining concept. This means that at one time a student has access to the resources, and then other students gain the access, and so on. The access cycle is repeated so that the students will not observe the interruptions.

The connected students are kept in a queue. More identical electronic circuits can be connected to the same NI myRIO. If the queue becomes to enlarge then, based on an algorithm, the queue is split on available electronic circuits. In this manner more students can perform the same lab work in the same time.

Keywords:

Remote lab, web services, multitasking.