Tag Archives: afm

Assessing Learning – Update

We believe that a low cost AFM could be a powerful educational tool.  A modular design that can be built in a variety of ways to make measurements of the nanoscale world encourages creativity  and participation in ‘hands-on’ science and engineering.

To get a feel for how school students would interact with a home-built AFM, and what they would be excited to explore with it, we carried out a series of workshops (in which Edwin and a team of students built his AFM kit from scratch and took images with it and also worked on a scaled-up, moving lego AFM model) as well as working with high school students on the build.

We also conducted interviews, which we translated and typed, with Tsinghua high school students at the summer school as well as participating PhD student mentors.  We found out that the group of students who worked with Edwin might understand more about how AFM works than the students that did not attend the workshops. This could be because the students that got to build an AFM from the beginning were introduced to how an AFM really works and the key components that it comprises.  In contrast, the students that worked on the build instead of attending the demonstration in general showed a less comprehensive grounding in their understanding AFM and its applications.

This finding suggested that AFM is perhaps better understood when students can be involved in assembling a kit from the beginning, step-by-step, but also that actually using the microscope is perhaps the most powerful tool to make students think creatively about its potential applications.  This shows the power that hands-on learning can have, breaking down a complex technique such as AFM in to something that students can not only understand but also begin to think of interesting uses or modifications.

When asked to explore what they thought an AFM kit could be used for, a variety of applications were volunteered by the high school students.  Interestingly, we found a general trend to be that the boys had more creative ideas, including but not limited to moving/manipulating atoms and building a nano-robot, whilst the girls had more realistic ideas (including a use as a quality control technique in the manufacturing industry).  We reasoned that all ideas, whether outlandish or realistic,  show creativity and engagement.  Moreover, in science often the strange ideas are the best ones!

It was also interesting to investigate what the UK/US-based mentors had discovered in their time working with high school students.  After chatting with several mentors, it was agreed that the high school students are very smart, interested and confident.  The depth of their knowledge base in areas such as electronics, manufacturing and computing was also very evident (most of them seemed to know complicated things that the mentors confessed to have learnt at university!).

More to come on Education soon!

Firmware – Update

You may have been wondering what is firmware; it is the part of the AFM that sits between the software interface and the electronics that control the microscope. This means that we need to take care of two tasks: first, to listen to the interface and translate that into a signal that controls the scanning stage. Secondly, we need to measure the signal from the AFM and send it back to the interface. These tasks are accomplished using an Arduino and a microcontroller that we can program to read & write voltages. To do all these things at the right time and in the right order, we control the behaviour of the Arduino using C++ code, we wrote this over the past two weeks. Continue reading Firmware – Update

Mechanics – Update Four

After talking to our “mechanics consultant”, Tom, we decided to redesign the stage and the stage holder so that we could use the dvd head holder that comes with the dvd head. It has some nice features that we could take advantage of, such as a cog system which could be used for coarse movement of the dvd head over the sample, and screw holes that we could fit the precision screws into. This means we don¹t need to have such a complicated design, with the old dvd head and flexure stage abandoned. Continue reading Mechanics – Update Four

Mechanics – Update Two

Yesterday we worked on finishing up the CAD files for the DVD head holder and the flexure stage that will be used for coarse motion under the piezos. We also bought some foam and made the sound insulated box that will be used to shield the AFM. We bought some acrylic at the architecture department and will be going back to the high school to laser cut and 3D printing the various pieces we need to build the project.

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