# Experiment Information System Based on an Online Virtual Laboratory
## 1 Introduction  
Traditional engineering experiments are often carried out in small groups, at specified times and in fixed laboratories, with custom lab benches. The traditional experiment teaching model is widely recognized in the long-term teaching practices, and it provides users with hands-on and intuitive experiences with experiment components and measuring equipment based on a universal or custom lab bench. With the development of computer graphics and visual technologies, more conceptual applications are emerging in the field of education. Among them, virtual laboratories have been broadly accepted as a potentially effective alternative to traditional engineering courses, such as science simulation [1, 2], process technologies [3, 4, 5], signal and control systems [6, 7, 5], and robotics and teaching models [8, 9, 10]. Experience has shown that students can benefit from the flexibility of virtual experiments and strengthen their innovative capability and logical thinking. However, fully software-based virtual laboratories also have inherent drawbacks; for example, students may feel as if they are playing a video game [11, 12, 13]. This study, therefore, agrees that the final training process still needs real equipment [11] and attempted to explore a blended learning scheme that mixes a virtual laboratory and real-world experience based on a university digital circuits course, to achieve a balance in learning enjoyment [14] and knowledge acquisition.  
In recent years, there have been two main viewpoints on implementing virtual laboratory systems: web-based remote laboratories [7, 8, 15, 16, 17] and fully software-basedvirtual laboratories [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 18; 19; 20; 21; 22; 13; 14]. A remote laboratory tries to carry out online experiments by operating physical equipment from a distance. They are usually complex, consume large amounts of bandwidth, and have high requirements for sensory-control hardware and software. Hence, this paper primarily discusses fully software-based virtual laboratories. A number of studies have elaborated their methods to implement virtual laboratories [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 18; 19; 20; 21; 22; 23; 1; 24] in various educational applications. Few virtual platforms aim to realize generalized software that may be applicable to multiple disciplines. Two representative works include the \"Go-Lab\" project [18; 19] and the \"Lila\" project [20], while most of the rest are specific to different fields. A virtual chemical vapor deposition (CVD) laboratory [4] emphasizes the training of students in experimental design abilities. The Virtual Laboratory for Robotics (VLR) [9] is a classic example of robot simulation. More recently, an instrument-based virtual laboratory [21] simulates an environment for electromagnetic phenomena. Work in Reference [22] realized a cloud-server-based virtual laboratory used in network security teaching and practice. The literature from Reference [23] proposed two methods to help implement virtual laboratories. In Reference [24], an NCSLab (Network-Based 3D control laboratory) was reported for a control system, and then [PERSON] et al. [25] presented a design approach to facilitate the establishment of virtual laboratories in an HIL (hardware-in-the-loop) control system. An investigation in Reference [26] verified that students' learning with virtual laboratories in experimental courses could achieve similar effects as using traditional laboratories.  
However, some improvements may still be possible. The main implementation tools in Reference [25] include 3 dsMax and Matlab, which could be updated by new ones. Additionally, most courses with a virtual laboratory are too dependent on the online section. Therefore, the main contribution of this study lies in two aspects: using the new technologies to design and implement a virtual laboratory and adopting a blended learning scheme to balance the online and offline sections in light of the investigations on blended learning approaches [27; 28; 29].