Author: ajohara

What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).

This week, I worked with Anna to finalize our final presentation slides during the first half of the week. We also received our new RPi 4 this week, so we spent some time getting the RPi up and running with all the functionality we’d implemented before our other RPi had burnt up. Once we got that working, we  were eventually able to get all the motors working as intended with the protoboards that Anna and I had soldered last week. After verifying that all 6 worked with our GUI code, I was able to attach all the motors to the dispenser coils I’d made earlier and mount them all inside the vending machine. In the midst of burning out the RPi, we’d also found out that our speaker bonnet stopped working (most likely burnt out) last week, so we had to order new speaker components. Once this was delivered, I worked on soldering the connections onto the new bonnet and integrating speaker code with the GUI. At this point, we were able to get everything electrically integrated and mount all of our components into the machine. We had to do some integration tests to debug some of the main dispensing functionalities and make sure that the timing of all the components made sense, like getting rid of some obvious lags between when the snacks would get dispensed and the LEDs + speakers would do their thing. Once this was finalized, I worked debugging and integrating the proximity sensor to make sure that it’s functionality conformed to what we had outlined in our use case requirements. This mainly consisted of tweaking the sensor sensitivity + output hold time, as well as playing around with some logic relating to when the timer would pause and resume, since we needed to factor in the fact that the PIR sensor would generate a response only when it detected motion, rather than continuous presence (what we want). Once this was integrated, we were able to get some end-to-end tests recorded.

Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule? 

My progress was behind schedule after our road bump last week with the burnt out RPi, but it was made up for with everything that we were able to accomplish this week as a team.

What deliverables do you hope to complete in the next week?

This upcoming week, my focus will be on getting the final poster finished, as well as prepping for the final demo and reports due this week.

What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).

This week, I mainly focused on getting the rest of the motors to work. We consulted a TA to help us figure out why expanding the motor driver circuit to power all 6 motors kept giving us problems (burnt out components), and we deduced that it was probably due to the breadboard’s inability to handle the amount of current needed to power all 6 motors. We were advised to migrate the circuit to a set of protoboards to handle this issue, so throughout the second half of the week, Anna and I worked on soldering the motor drivers to their own protoboards. We were able to successfully test each of them one at a time on their own with the power supply/voltage regulator still coming from the breadboard and verify that they worked, but when we then moved the power supply onto its own protoboard and tried to spin the motors using the motor drivers again, they would jitter inconsistently and never respond to the motor control code. I’m thinking this might have been an issue with bad connections between the voltage regulator and protoboard, but when we measure the inputs and outputs between the regulator and drivers, their values were as expected. Just as we were debugging this, we also realized the RPi had turned off unexpectedly.  We weren’t sure if this was a coincidence or a result of the potentially faulty regulator/driver connections, since the only thing that was connected between the regulator and RPi circuits was a singular ground pin, but unfortunately we haven’t been able to get the to RPi turn on again. After consulting the internet, it seems like we fried our RPi, since only one red light was blinking, indicating that the Pi wasn’t reading from the SD card. We were able to put in another purchase order for a new RPi 4 and are currently also borrowing an RPi 3 from Professor Benson in hopes of getting something to work before our final demo next week.

Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule? 

My progress in pretty behind due to the unexpected setbacks we experienced. We’re probably going to put all our efforts this week yet again to rebooting our new RPi and trying to get back to where we were last week and hopefully have some motors moving.

What deliverables do you hope to complete in the next week?

This upcoming week, my focus will be on getting the RPi to work with our original environment and get some motors to spin.

As you’ve designed, implemented and debugged your project, what new tools or new knowledge did you find it necessary to learn to be able to accomplish these tasks? What learning strategies did you use to acquire this new knowledge?

Throughout this entire process, I was able to learn more about the RPi environment and how versatile it was in being able to support project like ours. I also found however, that integrating multiple peripherals was not as easy as it seemed. In the end, we were able to get each component working to some extent as needed for our project, but most of the issues would come in making them work altogether. Because of this, one of the skills I found myself developing the most was being able to identify a root cause. This not only took persistence, but also tested my understanding of how each component worked, since identifying a bug required me to identify discrepancies between an expected output and a real output. I was able to utilize forums and example tutorials which were posted online to help me with debugging, which in the end was what I think contributed the most to my learning. I also learned the importance of good time management, especially for a large project with a long timeline such as this one. Being able to accomplish what we had required lots of planning, communication across our team, and an ability to prioritize.

What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).

This week, I mainly focused on getting the speaker and motors to work. I started working on debugging the speaker system, picking up on where David and Anna had left off earlier and checked all the connections between wires, as well as the code and packages which were in the environment. With Anna’s help, we were able to clean up some of the connections between the RPi and speaker bonnet, which in the end is what seemed to help up us get the speakers working. I then moved onto developing the code to get the speaker to play sounds on command, since that is what our system will need to do. Eventually, all we needed to end up doing is downloading pygame and using their libraries to play .mp3 sounds. However, we ran into a bug with the RPi config file, which prevented the RPi from producing sound when the pygame code was run. We eventually realized that our config file was missing a line of code which was what was responsible for actually enabling audio output on the RPi. We still need to integrate this with the rest of our code, but we decided that getting all the motors to work would be the priority at this point.  Once we got this working, I spent the remaining time working on helping David debug the motors. I worked with Anna to rewire the motors on the breadboards to see ach connection more clearly, but after connecting the motors, and running our code which we had previously been able to use to spin two motors, none of them ended up working anymore. I’m wondering if it might be a result of fault connections or motors drivers entirely, since we’ve been having lots of issues with these motors drivers specifically. We have yet to finish debugging, but once this functionality is working, all we’ll need to do is integrate and we should be good to go in terms of our MVP functionality.

Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule? 

My progress is on schedule with our original Gantt chart we made.

What deliverables do you hope to complete in the next week?

This upcoming week, my focus will be on getting all 6 of the motors to work during the first half of the week and then hopefully integration during the second half.

What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).

This week, I mainly focused on finalizing some parts of the enclosure; namely, finishing the manufacturing/assembly of the front panel window, as well as getting the springs we’ll be using to dispense the snacks from the machine to attach to the springs. This mainly consisted of me working in CAD again to design these mounts, laser cut everything, and attach them to the springs and motors. Right now, rotational movement from the motors is not being translated well to the springs. There’s some jitter that occurs when the springs begin to turn, which I’m assuming is a result of not having the mounts coupled tightly enough to the motor shaft, something I plan on fixing later on. I also assisted in attempting to debug the speakers with David and Anna, since the initial tutorial we referenced to set the speaker up ended up not working for us. I tried to look at other websites and blogs for possible fixes, but unfortunately none of them ended up helping us get the components working. 

Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule? 

My progress is on schedule with our original Gantt chart we made.

What deliverables do you hope to complete in the next week?

This upcoming week, my focus will probably be on integrating all the parts into the gui again, and possibly further finalizing code. I’ll also put some more effort into trying to debug the speakers again and potentially also help bring up the new PIR sensor we plan on replacing our ultrasonic sensor with. 

What did you personally accomplish this week on the project? Give files or photos that demonstrate your progress. Prove to the reader that you put sufficient effort into the project over the course of the week (12+ hours).

This week, I focused largely on getting the peripheral components to work + integration between parts. More specifically, I worked on helping David debug the motor driver circuit + code so that we could control the motors with the RPi. This consisted of looking through tutorials, as well as other existing projects which had also incorporated the same components we were using to try and see what the problem in our circuit could be. I also spent lots of time measuring voltages and currents across the circuit to make sure they were what we expected them to be.  In the end, the problem seemed to end up being incorrect motor driver step settings and also not having the GPIO output step pins oscillate between high and low at a high enough frequency. I was  able to extend this control to 2 motors, but since we ended up burning out some of our motor drivers in the debugging process, we’ll have to wait until our new motor drivers come in before attempting to integrate all 6 motors together. I also helped out Anna with integration between the LED and GUI – more specifically, figuring out how to configure the python environment we made for our LED strip functionality to work with the GUI libraries we were using. Since neither of us had super extensive experience in using python environments, we relied on forums to help us debug. In the end, we were able to begin integrating our existing motor and LED control code with our UI. 

Is your progress on schedule or behind? If you are behind, what actions will be taken to catch up to the project schedule? 

My progress is on schedule with our original Gantt chart we made.

What deliverables do you hope to complete in the next week?

This upcoming week, my focus will probably be on helping to get the rest of the peripherals (sensors + speakers) up and running. I will also try to clean up some of the motor control code + extend the functionality to 6 motors so that when the new motor drivers come in, integrating those will be a lot easier.  I also need to laser cut the clear window on our front panel and get that attached, although I don’t anticipate it taking a long time. I was also planning on laser cutting some motor attachments to make it easier to connect the springs to the actual motor.