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Team Status Report for Dec 4 2021

As this is the week of Final Presentations, our team did not make much progress in or outside of class. In addition, many of our other courses have final exams, presentation, project deadlines, and more that are piling on in the next few days. Aside from some minor adjustments on the web-app, our team has nothing of significance to report this week.

However, we are comfortably on schedule to present a proper final demonstration. Three chair sensors have been fabricated, two of which have been thoroughly tested. We have successfully ran complete integration tests from the chair to the web-app. The only outstanding tasks are: activate the second data hub (see Jonathan’s post this week for more details), brush up the web-app frontend, and debug the sleep cycle for the chair sensors.

Looking forward to a productive week ahead, and a smooth final demo!

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Team Status Report for Nov 20 2021

We made fantastic progress this week! The chair module and data hub integration are nearly complete. Our final components arrived, including more Xbees and the batteries for the chair modules. We were able to configure everything and the chairs can now run off of battery power.

Going forward the only risks we can foresee would be the battery life of the chair modules not being as long as we aimed for, and also the frontend of the website not performing to our original specs. This next week the team will finish up testing which will include getting a metric on how long we expect the chair module batteries to last on a single charge. We also aim to flush out the entire frontend this week in time for the presentation and demo.

We made a small change regarding how updates are sent from the chair module to the data hub. We now have the chair checking for changes in occupancy every 5 seconds. If there is a change, it will send an update. The data hub also then sends current state to the backend every 10 seconds. This configuration allows us to meet the 15 sec requirement, even when a single update is not caught by the data hub in the worst case.

We also had to order Xbees with antennas since the original PCB antenna Xbees were sold out. This resulted in some higher costs but did not affect the functionality of the project. In fact the Xbees with large antennas should have even better range than those with PCB antennas.

Because of our great progress this week we are definitely on schedule now. This week we just need to focus on testing and finishing the frontend of the website.

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Team Status Report for Nov 13 2021

This week, progress has been moving along very well and we were able to present our progress during the demo.  Each of the three main parts of the project (Chairs, Hub, Web) were functioning which was ideal. Now, integration is our next step.

What are the most significant risks that could jeopardize the success of the project? How are these risks being managed? What contingency plans are ready?

Regarding risks, we were able to overcome most of the main risk of the capacitance chair sensors not working. They work well, but need to be improved and made more robust. There are some instances where the threshold value to classify “Occupied” is too high/low, so this needs more calibration. This risk is being managed in our schedule, as we allocated time for this and are on schedule.

Another is the risk of delayed shipping of our parts. We are still waiting for some parts that were delayed in ordering, including Xbee modules. This is allocated for in the ‘slack’ time that we have.

The biggest challenge so far is the Xbee communication. This is mostly an unknown at the moment given the lack of hardware received so far. This also is accounted for in the schedule. If Xbee communication does not work, we have a backup plan of using Bluetooth which the hardware modules support as well. This is not as efficient but at the very least guarantee us correctness and functionality.

Were any changes made to the existing design of the system (requirements, block diagram, system spec, etc)? Why was this change necessary, what costs does the change incur, and how will these costs be mitigated going forward?

No design changes were necessary this week. The amount of prior time spent designing is beneficial, as now, as a result, the implementation part is smoother.

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Team Status Report for Nov 6 2021

This week was a productive week for the team. Not only did we all individually make great progress on our components, but have started making steps towards integrating all three together. Most of the week was spent working on our individual components in parallel. For details on each component’s progress, please refer to the responsible team member’s weekly status report.

The chair sensor has been prototyped and tested, with promising results. In addition, the hardware connecting the XBee module and the arduino has been completed, and configurations are underway. On the software side, the Data Hub python code has been installed on a RPi 4, and updated to include the GPIO and serial libraries and functionality. For the web application, the backend has been connected to the database, deployed, and a public API endpoint has been published for Data Hub interaction.

In terms of our schedule, we are slightly behind, but have also realized that our original schedule was slightly ambitious. Despite being behind according to our initial gantt chart, we may still be able to complete integration and testing before Thanksgiving, as planned. This is mainly due to our underestimation of fabrication times, and overestimation of testing difficulty.

Next week, we hope to finish connecting the XBee modules, and complete one integration test, sending data from the chair to the data hub, and finally pushing data to the web app.

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Team Status Report for Oct 30 2021

Going into this week, the largest risk for our project was the capacitive sensor and getting it to work to detect occupancy in a chair. Without a functional sensor our entire system becomes worthless. We worked outside of class time this week to configure the hardware for the capacitive sensor to see if our current plan of utilizing the Arduino Capacitive Sensor library was viable or not.

For the capacitive sensor we developed a working proof-of-concept! We put a piece of aluminum foil underneath a chair with a wire attached from the foil to a digital pin on the Arduino. We also used three 10MΩ resistors to form a 30MΩ resistance between the receive pin and send pin that the library utilizes. We were able to sense a large change in capacitance using the library when someone sat in the chair and then stood up. We will work to refine the sensing and add some hysteresis for the sensor to be more robust in the future. A video of this proof of concept can be seen on slack here:

https://18500f21.slack.com/files/U02B5N4M0AH/F02KFNDMF9Q/image_from_ios.mov

Our other risk factor going forwards is the Xbee communication. We are fairly certain we can get Xbee to work between the Arduino Pro Mini and the Raspberry Pi, but this is a vital part of our project and if something goes wrong we will need to do a large pivot to get communication working. Zigbee is the route we want to go, if the Xbee’s we bought lead to issues we could consider other modules that support Zigbee communication.

The only design change we made this week was the battery we will need to use. After talking to Joel we think we will order a high capacity LiPo battery which should be better for our needs than using 6 AA batteries. We still need to order a battery and test it out, which we will focus more on once we get the Zigbee communication working.

No major changes were made to our schedule, we are on track now especially after getting the capacitive sensor to work.

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Team Status Report for Oct 23 2021

This week, we were able to reflect together on some of the ethical problems that came with our project. These include:

-Someone viewing FreeSeats to steal things when people aren’t there.

-Finding a single person in the library alone as a target for theft or violence.

-Exclusionary to people in wheelchairs.

We thought of solutions to remedy these issues, such as displaying only range of available chairs instead of specific values. Also, we can extend our project to account for those with disabilities with weight sensors if time permits. We will continue to keep these ethical problems in our minds as we implement our project.

What are the most significant risks that could jeopardize the success of the project? How are these risks being managed? What contingency plans are ready?

Progress with the team has been excellent. This week, we focused on the initial implementations of our project. We have been communicating extremely well and feel confident as a team moving forward.

Some risks we face moving forward is the workload of our other courses. As the semester picks up, we all have more auxiliary work to complete. However, we are all on the same page about keeping our Capstone project a high priority. This way, we stay on top of the schedule and make good, incremental progress.

Another is the risk of delayed shipping of our parts. We are gradually receiving the hardware parts we ordered as expected. This includes batteries and Raspberry Pi. However, some of the parts may be delayed this week. We have accounted for this risk by incorporating “slack” time in our schedule so that there is buffer time available. Right now, we feel confident we have enough work to do before the incoming parts arriving which is excellent.

The biggest risk is our hardware capacitance sensor not working. The professor raised this concern to us. Though we feel confident that it will work based on our research , we have accounted for this risk by having a backup plan with the weight sensors. This “backup” plan time is allocated within the slack time for this portion of the implementation.

Were any changes made to the existing design of the system (requirements, block diagram, system spec, etc)? Why was this change necessary, what costs does the change incur, and how will these costs be mitigated going forward?

No design changes were necessary this week. The amount of prior time spent designing is beneficial, as now, as a result, the implementation part is smoother.

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Team Status Report for Oct 9 2021

This week, the class spent the two lab times giving our Design Review presentations, all of which were impressive and enlightening.

As such, we didn’t have any in-lab time to work, but our group coordinated well and got some meaningful research done in preparation for our Design Review writeup. Each of us cleared up unknowns within our respective focus areas, and smoothed out implementation details for the work we have to come. In addition, we have made progress towards finalizing our list of components to order, and are planning to submit the order form by tomorrow, Oct 10.

Next week, we plan to have ordered our full component list. In addition, we want to have completed our Design Review writeup early in the week, in time for the Wednesday submission deadline. Later in the week, we aim to start implementing some software, whatever we can get to before the hardware arrives. For some project components such as the web app, this will probably involve bootstrapping the web app stack. For the hardware-related project components, this will be writing the embedded code that will run on the respective devices. Achieving this will put us right on schedule!

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Team Status Report for Oct 2 2021

Progress for our team has been going great. This week, we focused on narrowing down our design in preparation for our design review presentation. Nathan has been diving deeper into the web app and cloud/database side of the project and has scoped out a great plan. JJ has been doing further research for the data hub and how we will implement a solution using a Raspberry Pi. Will has been scoping out the chair module, which includes deciding which type of sensor, microcontroller, and battery to use.

Going forward, there are many technical risks regarding the design we have chosen. After presenting our design in the design review, we will go forward with trying to implement it that way, but we might have to adapt and change plans if things don’t go how we expect. Some examples include if the batteries we get don’t connect or perform as expected, or if the chair sensors aren’t accurate enough.

We changed our design to use an Arduino Nano for the chair module instead of a NodeMCU, due to the Arduino consuming less power (hopefully). Also, we are going to switch the chair sensor to possibly using a piece of conductive aluminum along with the CapSense Arduino library. This change is something we’ll need to test, so we might still go back to using the load sensors, but those would be much more expensive and require an amplifier board. We didn’t encounter any significant changes with the web app or data hub.

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Team Status Report for Sep 25 2021

What are the most significant risks that could jeopardize the success of the project? How are these risks being managed? What contingency plans are ready?

Progress with the team has been excellent. This week, we focused on the project proposal presentations. It went very well! Great job to Nathan!

Some risks we face moving forward is the workload of our other courses. As the semester picks up, we all have more auxiliary work to complete. However, we are all on the same page about keeping our Capstone project a high priority. This way, we stay on top of the schedule and make good, incremental progress.

Were any changes made to the existing design of the system (requirements, block diagram, system spec, etc)? Why was this change necessary, what costs does the change incur, and how will these costs be mitigated going forward?

Nathan has been switched to primarily dealing with the software stack, and Jonathan has been switched to dealing with the data hub components. This change was made due to a better fit of interests within the project. This will allow us to all make more progress in the project as we will be maximally engaged. Other than this, no changes were made as research is still going on for each aspect of the project. No changes were made to the schedule either.

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Team Status Report for Sep 18 2021

We met with Professor Mukherjee and our assigned TA Joel to get feedback on our abstract. The feedback gathered included needing to refine our scope, figuring out which sensors to use, and coming up with more concrete requirements that relate to the problem we are attempting to solve.

We came up with a more feasible testing plan which includes testing 6 chairs, not an entire library. We also researched different sensors and embedded systems to use, including how Zigbee will fit into our system.

We worked on the slides for our proposal which are due this weekend. We developed a Gantt chart to schedule how we will meet our goals throughout the semester as well.