Three Point Bend Experiment - Lo-Fi html Simulator - University of Sheffield

A virtual "digital twin" experiment using web browser html of the 3 Point Bend test delivered at the department of Multidisciplinary Engineering Education at the University of Sheffield.

The Faculty of Engineering at the University of Sheffield also developed simple, web browser based simulation. The term “simulation” can often imply sophisticated in-silico prediction tools such as CFD (Computational Fluid Dynamics) or graphically rich interactive experiences such as iVR. In contrast, the simple, browser based simulation developed here is referred to as “Lo-Fi”, as it is simple, both in terms of its graphics and modelling approach. 

The Lo-Fi simulation is written using html and javascript, allowing experimental systems to be constructed using standard graphical elements such as sliders, text boxes and buttons to collect input parameters and text or numerical output, as well as pre-built illustrations of the apparatus. How the webpage responds can be programmed to replicate the physical system.  While there are some priority software systems that allow these types of dynamic pages to be created, the objective at Sheffield was to create digital tools that are virtually frictionless for students to access, i.e. no accounts to log into or software to download, and can be shared with other educators to reuse or adapt. In addition, there is no further hardware requirement for the construction of the Lo-Fi simulations, beyond a computer running a text editor and a web browser. Web pages can be sent directly to students as html, although hosting on webspace and sending a link makes access easier.

In the three point bend test the beam specimen can be selected from a drop down list, the force applied to be specimen can be adjusted with arbitrary precision within the 0-700N range using a slider, and the resultant deflection is then displayed. In addition, a graphical representation of the extent of the deflection is displayed based on a finite number of pre-built digital vector images. The resultant deflection is calculated using empirically measured coefficients of proportionality between force and deflection on each sample. The deflections should thus match both the iLabs results and those obtained with the real equipment.

The complexity of the Lo-Fi simulation can be chosen based on the amount of time the educator has to invest in its development and their experience with building web pages using html and javascript. In the simplest case, a text entry box could be used to input a variable (applied force) and an output box could display the output (a deflection). An interesting feature that was programmed into the 3 point bend test and could be created for other simulations was the introduction of experimental error. With the standard javascript random number generator, each time a result is generated a predetermined amount of experimental error is added to the output. In fact, there is a specified amount of random and systematic error to all results to allow students to more closely represent what students may expect from the physical set up.