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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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Cole’s Status Report for Feb 22

This week I reviewed design presentations and helped to work on ours.

After receiving parts and creating the design presentation I was able to start conceptualizing the size, material, and general design of the housing that will hold LiPo batteries and the Raspberry Pi. At the moment the box will be laser cut out of wood with the interior and exterior in aluminum foil to keep the internal temperature steady while preventing the proximity to the fire from increasing the internal temperature.

I also helped to test the amplifier using a power supply, wave generator, and an oscilloscope. Learning how to hook everything up and power it took a decent amount of time on Saturday but we ran at least 1 successful test with the amp.

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Kushaan’s Reflection for 2/22

This week, I finished setting up the PI. I was able to ssh into it and started setting up the python environment. I installed the necessary packages and troubleshooted some installations. I started running some benchmarks of the base yolo model we want to get an idea of any inference time issues. I also set up the github for the fine-tuning, proof-of-concept, and final code. I will be working on the fine tuning code on Sunday.  I set up sshing and internet on the Pi as well. Once I finish the benchmarking, I will try different serving frameworks to see if the inference time can be further reduced. While doing fine-tuning, I will be writing boilerplate code for the logging, so we can see how the ML model influences the pipeline. I also looked into manipulating GPIO on the Pi.

In addition, I worked on the circuit to test the amplifier. We wanted to make sure the amplifier worked at lower wattage, because we don’t believe we can power it at full spec. However, if it runs at lower spec, we can hit the wattage requirements of the speaker, which is the important part. I helped diagram the circuit, and use the signal generator, DC-power supply, and oscilliscope. Ultimately, we were able to boost a 60Hz wave from 100mV to 600mV. We used a very conservative amount of amps, 200mA instead of the ~2-3A we expect to be running at full power.  We need to perform further testing once we are more confident about this circuit, but it should be fine because our ESP outputs 3V, so we should hit our required ~80W into the speaker.

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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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Team Status Report for Feb 15th

This week we had our first successful proof-of-concept test! Using an app on our phones we were able to generate a 60Hz wave that put out a candle several times. To ensure our test was what we believed was going on rather than simply the air from our phone speaker we played a song at full volume at the candle. What we observed was that the song at full volume was NEVER able to extinguish the fire while the 60Hz wave consistently able to.

We also worked on our design presentation this week, incorporating feedback we received from Gloria Chang to better specify the parameters and our Minimum Viable Product.

Our next steps will be presenting this week and giving feedback to other groups. We also hope to receive the parts we ordered so that we can start assembling the parts and running tests using the full size sub-woofer magnet.

 

 

A: We are aiming to build a non-invasive, reusable fire extinguisher. This addresses a significant gap in current public welfare. With fire extinguishers that exist now a human being has to identify a fire, react quickly to find the nearest fire extinguisher and then spray a foam on the fire that puts it out. Now what was previously on fire is covered in a foam spray that needs to be cleaned off. We are eliminating all of these by having a device that can identify the fire on its own, fully extinguish the fire within 20 seconds, and it uses sound waves that will not have to be cleaned after use.

B: Does not apply. Our project aims to eliminate the human factor of a single user application and thus does not have a social interaction implication.

C: Currently, fire extinguishers expire and need to be replaced regularly. We are planning to offer a solution with rechargeable batteries that will not expire. Our solution will certainly have a higher initial cost than the ~$80 that a fire extinguisher costs, but because of the longer lifespan our solution will cost less amortized over decades.

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Kushaan’s Status Report for 2/15

This week I looked into the Raspberry Pi more in-depth, and also into thermal camera imaging. I looked into benchmarks regarding different inference frameworks, and their benefits. I settled on using PyTorch to begin with, as it is the easiest to proof-of-concept with. Then, I will try using more advanced parallelism frameworks. I also looked into some depth-estimation models, since this will be an important part of our product. I found a few models that look promising, but want to do some benchmarking.

 

We got the RPI this week, so I will be running benchmarks over the weekend on these models, to verify the numbers as well. I want to generate intuition for the accuracy and limitations of these models.

 

I also worked on the design presentation, primarily focusing on my sections, and updating the theme and visuals, since I will be presenting

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Cole’s Status Report for Feb 15th

This week, I focused on researching suitable lithium polymer (LiPo) batteries to power an amplifier and reviewed the code for a chassis kit sourced from Amazon. The aim was to ensure compatibility, efficiency, and safety in integrating these components into our project.

 

After looking at LiPo battery models and specifications suitable for powering the amplifier and analyzing battery capacity, discharge rates, and form factors to meet project requirements, I settled on 2200mah 3S 30C LiPo’s to power the microcontrollers and chassis motors. For the speaker and amplifier I chose 1500mah 4S 120C LiPos to power the speaker magnet. After reviewing the code that came with the chassis kit it looks like the vast majority of the work has been done for us. We likely will only have to change the pin connections in the code, wire it to the GPIO pins on the Raspberry Pi, and call the prewritten functions.

The next steps will be continue work on the design presentation and help assemble the equipment we ordered for the first test.

 

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Team Status Report for 2/8

Currently, the biggest risks for our project lie in robotics and the results of our testing. As a group, we don’t have tons of robotics experience, and this will be an important part of our project. We feel we have enough similar technical skills to figure this out, however. During the presentations, someone raised the concern of the impact of smoke. We want to test our behavior under smoky conditions, but also have a contingency involving thermal camera sensor fusion. 

 

Our progress is on schedule so far. Currently, we don’t have any plans to change our design, but we are planning to do more due diligence next week. There may be changes during this step as we solidify the design.

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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.