Author: tsaha

This week, I worked on two tasks in particular. The first task was to divide up what needed to be done for the report and make some progress on it. We divided up the necessary sections amongst us, and I am taking the parts with Architecture and System Implementation. I have already started working on some of its content in order for it to be ready by Wednesday’s deadline.

The second task that I accomplished was testing the long force sensitive resistor. First, I will present my data and circuit. Then, I will talk more about how this information will be used to further our project.

While trying to test the sensor at my home, I realized that I didn’t have a way to measure weights of objects. Therefore, ‘force applied’ and ‘sensitivity’ columns are blank for now. I will measure the objects I used later in lab.

• FSR is finnicky at smaller amounts of force. However, we don’t need to worry about that for our application which will have comparatively larger forces.
• Small movements change the values by <100. This is most likely due to weak connections on the breadboard. These errors can be eliminated when we solder the sensor.
• The sensor needs to be as flat as possible for reliable results.
• As shown in the data, smaller resistor results in lower measured values. This will be ideal for the big forces like a person’s weight.
• It is not foldable in the circle shape. Z shape might be possible but can end up damaging the component.
• I will discuss this more with my team, and we will probably end up using more and smaller sensors per square. This will also mean that we use the digital pins of the Arduino and set threshold using the appropriate resistors rather than on the software.

I will gather more testing data with people stepping on it in the future. This will probably be done after the switch to the other smaller sensors. For next week, I will figure out how Arduino should send data to python. So far, I am on track with my schedule.

 

This week, most of my time and focus was spent on two tasks. The first task was the Design Review presentation. We worked on a document together to write down everything we needed for this design review including notes from the peer reviews and the helpful meeting with the professor and TA. A lot of individual time was spent by each of us filling out this document. We designed our presentation based off this document. I particularly took the responsibility of the slides related to the use case, use case requirements and implementation plan. I will also be the one presenting this following week. Therefore, I have already started preparing notes for what I will talk about during the presentation. I will rehearse it a couple of times alone and in front of my group mates to get feedback tomorrow (Sunday).

The next task that I worked upon was researching how circuits with the force-sensitive resistors and Arduino worked. I particularly found this website which gave clear instructions about what connections to make-

https://lastminuteengineers.com/fsr-arduino-tutorial/#:~:text=Force%20Sensing%20Resistors%20are%20also,pressure%2C%20squeeze%2C%20and%20weight.

I have already put some time into thinking about how I can modify the above circuit to fit our needs with the DDR mat, including adding a variable resistor to adjust the threshold. Unfortunately, the sensor that we ordered did not arrive yet so I was unable to test them. However, it should be here next week, and I will be able to test it with the modified plan.

If there are still issues with the sensor not being available next week, I plan to research more into how the Arduino would communicate with python and relay the necessary data.

For this week, I was particularly involved with the ordering of our necessary parts. As per our Gantt chart, my tasks for the next two weeks will involve testing out the force-sensitive resistors with the Arduino, and finding a way for it to communicate the information to the raspberry pi and Pygame. Both these tasks required us to have the necessary components by the upcoming week. Therefore, a good amount of time was spent choosing the right Arduino board (without headers which we could solder wires to) and the right force-sensitive resistor.

For now, we have decided to go with Arduino Leonardo without headers and 2 feet long force-sensitive resistors (FSR). For the FSRs, I plan to utilize the IDEATE resources to test out other smaller FSRs they already have available. After researching for a bit, the ones I plan to test are:

As for Pygame, I am definitely behind schedule for learning it by this week. Although I am mostly involved with the circuits in the project, I still want to contribute to programming the interface towards the later half of the semester. As such, I have reorganized my schedule next week to completely devote couple of hours to understanding how Pygame works. I will mostly be using resources on Youtube and documentation on Pygame.

I am aware that the Design Review Presentation is due by the end of next week, and I will also be the one presenting. As this will take an ample of time, it may result in the delay of testing the sensors. I plan to make up for it in the following week by allocating more hours to it.