Author: ndwalker

The past two weeks, I have assisted with verifying the circuit for the PCB, made the interface code for the pedal, created test codes for debugging the pedal, met with Chaitanya to debug the interface code, modified the plans for the 3d model due to changes with the PCB, and made designs for the input circuit. The interface code is mostly working, with only the buttons and the rotary encoder still having issues, but this is likely due to some confusion with the Daisy library, as the classes for switches and encoders seemingly are in progress. I have already made some alternate files to test possible solutions and am working on making versions of the code that use the standard GPIO class, which we know works as I used it for the other components, but I am hoping that we can get the Daisy classes working as their debounce function would likely work better for our pedal. For the 3D model, after learning that the PCB size would be much larger than initially planned, I remade the models to fit the new PCB and sliced them, and it seems that the base at this new size would be too expensive to print, so I moved the holes for connections in the base to the faceplate, and will find a premade plastic box that we can use as the base. Overall, this shouldn’t affect the functionality. Our progress seems to be slightly behind, although not by much, as we should be able to catch up early in the week and hopefully start testing. Next week, I will fix the last few things with the interface code, add the holes to the faceplate model and send it for printing, finalize the breadboard version of the circuit for testing, start testing once the audio processing code is fully converted to C++, do my part of the presentation slides, and prepare for the presentation.

As for testing of my own subsystems, as of now, I made most of the circuit in tinkercad while we were designing to test functionality and have made and modified multiple test files for the interface code to debug the individual subsystems of the interface. For the tests I plan to do in addition to the tests we are doing on the whole system as discussed in the team report, I plan to test the system with the full code and compare it to a preset input with just the audio code to determine if there is any significant impact from the interface code on latency, and plan to test the overall noise impact of some of the changes in our design.

This week, I was unable to work much, as I was sick and had a major lab for another class. With the time I had, I researched some other daisy projects to make a plan for the device code for our pedal, so that we can start integrating everything. My progress is slightly behind because of the setbacks from this week, but I have plenty of time in the next two weeks to make up for it. Next week, I hope to get the base of the main code done so that we can test the code Chaitanya has been working on with our audio processing code, and I also hope to get the 3D model finished if the PCB is done in time.

 

This week, we started by doing part 4 of the ethics assignment Monday. Then, I made the base of the 3D model for the pedal housing to confirm the initial design ideas with the group Wednesday. I can’t add the holes for the components yet, as the PCB layout isn’t complete yet, and will be mounted to the other side of the faceplate, but I discussed more with the 3D printing lab to ask about restrictions and design requirements so that I can add the I/O holes and send out the designs for printing once the PCB is finished. In lab Wednesday, we discussed the initial model and tested our audio input component to find if we needed to make any adjustments to our schematic. I also worked with Chaitanya further to fix some issues we had with the design, swapping out some parts and adding some components to deal with pin issues on our microcontroller. We are mostly on schedule, although we are having to shift some parts of the schedule around due to some work relying on other work to be completed. Next week, I will start on the implementation software, although one of my other classes has a major lab that will keep me busy early in the week.

 

 

This week, I did the ethics assignment, worked multiple times with Chaitanya to help finalize our hardware design, made initial plans for the housing model, and discussed restrictions for the housing model with someone from the 3D printing lab. We needed to finish our hardware design before I could start work on the housing model, since the dimensions of the model will depend on the specifications of the design. I did rethink my original idea for the housing to reduce risk, now planning to split it into 3 parts, with the top faceplate being its own part. This is because the faceplate is the part that relies most on the hardware design, so making it its own smaller part that can be slotted in easily allows me to make multiple possible designs and quickly adapt and refabricate the design if we run into any issues with our PCB design. Our progress has caught up a bit from where it was last week, and we expect to be fully caught up by the end of next week. Next week I hope to finish the models for the lower housing and the functional pedal, make an initial version of the faceplate model, do the in class portion of the ethics assignment, prototype with my group in lab to test some components we ordered, and start helping with the software if I have enough time.

The current most significant risks are in our PCB and our interface components. For our PCB, because of the time and cost it takes to get it made, we are unlikely to be able to fix any issues that come up after fabrication. To mitigate this, we are working to look over any possible issues that could come from voltage mismatch or positional issues, and have backup plans in case an issue still arises, including full backup perf boards already ordered and plans for smaller perf board designs that could be easily implemented along with the PCB if the issues are coming from the input or output. For the interface components, the main risk is that they do not work at all or as intended, so we will be testing all of them in prototyping over the next few weeks to ensure that they work. One major change was made to the existing design, with us getting rid of the row of buttons for pitch shift and adding their functionality to the LED buttons we are using for beat selection, with the pitch shift option on the slide switch altered to allow for this change. We did this after realizing that physical switches for the pitch shift buttons would not work if only one beat could be modified at a time, as they would allow for multiple to be turned on. The LED buttons allow us to provide visual feedback for a beat being unselected as another button is pressed. There are no major costs from this change, as it requires no additional hardware and just shifts some of the software work left to do around.

I wasn’t able to accomplish much this week as I got sick at the start of the week and it lasted for the entire week. With the energy I had, I prioritized finishing my part of the design report and preparing for two midterms I had for other classes. We are still behind for the same reasons we were before, as with midterms and my illness we didn’t have time to catch up on work, but we will in the next two weeks, so we will try to get back on schedule in that time. In the next week, I hope to get an initial version of the 3D model done to revise with my group, and work with Chaitanya to help with PCB work.