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Team Status Report for March 8th

This week we aimed to reach our MVP requirements. With this, we were able to get the speaker and amplifier components working together. The robot chassis was built, and the imaging model was able to detect different fires that we set up well. The most significant risk that could jeopardize the success is the what if case on not being able to extinguish a fire. More specifically, even with the speaker built, it was not able to extinguish the fire. However, we are currently still working towards the idea that using a collimator will be able to put it out. On the other hand, increasing the power would also be able to be tested.

There are changes to the existing design of the system that could or may not remain the same. That would be the existing RC filter that was initially implemented. We thought that this would help with getting rid of any noise and distortion, however, with testing this week, the amplifier itself was able to fine tune the signal so there was no need for the filter. Although, if needed in the future, it is still in consideration. Cost-wise, this doesn’t change in particular as all parts were able to be found in TechSpark and such.

Part A:

This product will meet the consideration of global factors as fires exist globally. No matter the country or continent, fires, especially at home and not wild, are found commonly. This product will be able to help individuals who live in an home environment extinguish fires with ease. Furthermore, it helps for those of all ages. Whether old or young, in different stages of life, tech or not technologically savvy, this device is easy to use and requires little to none involvement on the user’s end. Governments and international organizations all emphasize the importance of fire safety regulations, which is why this further fits with in consideration of global factors.

Part B:

This product does not apply with consideration of cultural factors. It does not apply as it has no part in beliefs, values, traditions, language, etc. Since it is a technical product for a technical use, it does not take part in any cultural factors. The purpose is for safety which is designed for a universal functionality which is why it considers global factors. It relies on scientific principles of fire extinguishing which makes it universal and independent of cultural factors.

Part C:

This product applies with consideration of environmental factors as one of the main reasons as to why we are using acoustic waves, is to eliminate harmful environmental consequences that traditional extinguishing methods dispose of. For example, the powder extinguishing method continues many different types of chemicals that have proven to be harmful to bodies of water, the ecosystem that takes part in the cycle of water, and the soil and ground around as well. It is hard to throw out the extinguisher as it is then considered hazardous waste, and furthermore, it would then have to be rebought to fight more fires. Our product is reusable and does not contain any harmful chemicals and does not damage any parts of the environment that it is used in.

Part A was written by Cole MacSwain. Part B was written by Kushaan Misra. Part C was written by Stephanie Mao.

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Steph’s Status Report for March 8th

This week, I helped our group try to reach our MVP requirements.

One thing was trying to pick out components for the RC filter which was initially going to be 1.2KOhm resistor and a 2.2microF since this would yield a cutoff frequency of 60.29. However, with further testing, the amplifier fine tuned the signal enough without noise and distortion which allows no need for the filter. I further investigated this and documented the total harmonic distortion graphs that I found in the amplifier chip’s data sheet in the design report. However, it may still be in consideration to be used in the future as testing continues.

Since I was not in Pittsburgh when the robot chassis came in, I was unable to work and help on it. However, I continued to help by documenting the project in the design report, putting in the use case and design requirements, implementation, and such.

This week, I plan to construct the collimator and attach to the working speaker and amplifier apparatus to see if this will put out the fire as intended. I also plan to help on test the robot and integrating the speaker apparatus with the chassis.

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Steph’s Status Report February 22

This week I continued research on the circuitry part of the design which includes the ESP32, RC filter, amplifier, and the speaker. I picked up the parts that came in and the amplifier specifically needed to be more looked into. The main thing was figuring out all the inputs and outputs of the amplifier board which would take in the signal through a 3 pin connector which would in turn be the breadboard from the filter and that would in turn be connected to the ESP32. From the other end of the amplifier board, it would take in power supply which would be between 36-48V and then the right and left connectors would be connected to the speaker magnet via ground and voltage. I am looking into purchasing the malleable steel sheets soon so that we are able to build the collimator as well with the cardboard being the interior structure.

By next week, since we have the speaker magnet, I want to construct the collimator with the cardboard and the steel sheets and then have that fitted. However, since next week will be the week prior to spring break and I will be leaving relatively early in the week, I hope that we can get more testing done with the amplifier and also get the parts for the filter.

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Team Status Report for February 22

This week, the design presentation and finalization of design were completed. Apart of that, we took in feedback on the timeline of our testing and since receiving the parts, we tested the amplifier. The following images showcases our circuit. A waveform is hooked up to the breadboard and the oscilloscope is connected to the amplifier. The amplifier itself is connected to the power supply and everything is connected to a common ground.

From this test, we were able to successfully boost our output from 100mV to 600mV with a 60Hz wave. Along with testing, we took more into consideration the heating concern as well as distance between the speaker and the fire. This would need to be continuously tested in the future which is part of our Gantt schedule already.

The most significant risk currently is trying to figure out the most ideal power supply to use to power the amplifier and all the other components in our design. This is concerning since we have a maximum of 50V and 10A which is really high, however, the plan that we currently have is to have 3 LiPo batteries in series with each other that are each 14.8V which would roughly give 44.4V (as long as it is between 36-48V).

As of now, there are no changes to the existing design presented at the design presentation this week. Moving forward, the only other costs necessary are the robot kit which we are waiting a little longer to buy since we want to fully focus on reaching  MVP first.

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Steph’s Status Report for February 15th

This week I started finalizing the design for the speaker apparatus and purchasing items. The type of amplifier was chosen (TPA3255) to be able to meet the specs of the speaker which would be 100W RMS and 8Ohm load. This chip would be able to meet the requirements with the downside of needing a higher voltage input than we anticipated so therefore we will be increasing the LiPo batteries that are needed. Another thing was adding in a simple low-pass filter before the amplifier part since we are using an ESP32-WROOM to generate the signal. I chose the ESP32 since it is able to generate the lower frequency range of 30-60Hz that we intend to test with while also outputting a sinusoidal wave.

Once I get the parts for the speaker and all the components, I want to start testing the ESP32 first and get the code working for that. I also want to get the specific parts for the filter and build that so it would be simple to connect everything further along.

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Steph’s Status Report for February 8th

In the past week, we put together the proposal presentation and I practiced for the presentation on Monday. On the day of the presentation, we received questions that we should take into consideration such as storing the signal into ESP32 for example. Along with that, I have put together a bill of materials spreadsheet that the team can keep track with on what needs to be bought, what has been delivered, and what we already have. While doing this, I have been researching and picking out the best subwoofer magnets to utilize and ones that would be most affordable but also hit our range of frequencies.

I hope to test fires with a standard speaker in the next week to get an approximate idea of the distance the speaker needs to be in relation to the fire. Furthermore, it would help to gauge how big of a fire we expect to put out.