17 June: First Day of MnT Lab (COVID-19 restriction lifted!)

We set up our raspberry pi and researched on the types of drivers and modules required to work with our motors and water pumps.

18 June: CODESYS (pronounced as co-de-sys)

We connected our raspberry pi to the touchscreen tried to code for the raspberry pi using CODESYS. CODESYS can use ladder logic or continuous function chart to programme the raspberry pi. In addition, there is the in-built visualisation software which can be used to create our own user interface. Below is our successful attempt to code using CODESYS to control a LED.

23-24 June: Terry Clips & CODESYS Problems 🙁

The terry clips we bought were not compatible with our test tubes due to the hole being too large. Hence, we decided to model our own terry clips. The 3d printed terry clips were of a better fit with the test tube. However, the clips were flimsy and the test tube could be easily slip out from the terry clip.

Bought Terry Clip

3D Model of Terry Clip

We modified our design by increasing the thickness and the radius of the circular portion. With the addition of rubber bands, it was harder for the test tube to slip out of the terry clip. Our final design allows the test tube to be easily clipped on and removed from the terry clip, and the test tube will not easily slip out of the terry clip during the washing.

Final Terry Clip Design

With the arrival of our stepper motor and its driver, we tried to programme the stepper motor. However, we had issues trying to connect our code with the port extender. The port extender was used to protect our raspberry pi in the event of a short circuit. After a whole day of troubleshooting, we were unable to fix this issue and we decided to switch to the arduino mega.