This week I focused on getting an initial design done for the DAQ. I also began to work through some of the challenges with the design. Chief among them are protecting the system from the environment and communication protocols. These ideas were mostly distilled through weighing sensor options and how each sensor would effect the DAQ system. In the group setting I attend our weekly Monday morning meeting and assisted the group in the planning for the week. We also finalized our Project Specs, but after some post submittal considerations we may need to do another pass on that. On Thursday, I went out to see the mine with the group. It was fairly productive but unfortunately we are unable to enter the mine this week. We were able to get some useful information out of the trip, especially in regards to selecting the location for power generation. The trip also allowed for good ideation for the DAQ, cooling system, control system, and power generation. We will document these ideas in our next Monday meeting I believe. A meeting with Shane has also been scheduled for next week Wednesday. Below I have attached the Monday Meeting notes and individual documentation of the DAQ for this week.
These past two weeks I have been focusing on building the initial design and ideas for the DAQ system into a prototype design. I worked through the design of the digital system and ended up selecting CAN for our communication protocol. I also laid out the design of the CAN commination boards for the sensors. We selected the Pi Zero as the micro we would like to run the whole system off of and figured out the items that would be needed to support this decision. I went then and made selections for the power system needed to run the DAQ. I wrapped all of this up together and placed an order for all the necessary components needed for an initial DAQ prototype. Coming in the next two weeks I need to order a few supplementary parts (wire and I think I might switch our buck converter for the Pi to a more integrated solution), work on our CDR presentation, and begin the prototyping. I hope to have a working prototype by the end of October. I do need to to put more work into understanding the low power mode and how we want to execute that. I may need to purchase some sort of timing ASIC. I also don’t entirely understand the CAN transceiver’s wake-up on CAN which we might use instead of a full on shutdown.
Parts are in for the DAQ. Ben is working on breakout boards currently and after that a prototype is going to put together. Big questions still, are flashing the microcontroller and getting the Pi programmed. Wire to be used should be ordered on Wednesday. While waiting on that, I have been working on the Power DAQ for solar panels. I have an initial design layout, but I’m still not confident on the solar panel specs so I have not specced out parts. Thomas appears to be having some issues on that front. Hopefully, on Monday we can clear the air on that and get parts ordered. I also have been coordinating with the local Professional Surveyors Society to get their assistance on getting a point cloud of the mine. Hopefully, we can plan our trip out to the mine soon. They would like a date for that trip by Wednesday, so another thing for us to focus up on this coming Monday. We may need to split up our trip into two trips.
Slow week on progress in some regards. Sounds like Thomas has gotten his hands on the solar panels but they are much smaller than expected (25W). Makes me worried about whether or not there will be enough power to run the Power DAQ off of the solar panels and still have a measurable power leftover. Not sure Ben is at with the breakout boards but it sounds like he has had some struggles with that. My plan moving forward is to see what the group thinks about Power DAQ at our Monday morning meeting. We will hopefully be putting our solar panels next Thursday and also be taking point cloud data of the mine. The Power DAQs will most likely have to be set out on a different date, which is fine. The solar panels need to go up soon because the road will become snowmobiles only once the snow stacks up and they will be too big to get out there. Focusing on getting everything ready for Thursday will be my goal for next week. Power DAQ is secondary and the normal DAQ will be last priority.
This week I focused on working on the SD card issue with the power DAQ. I did some research into the issue and it seems to be a two part issue with both the hardware and the software. To fix the hardware I need to identify the pin readouts whether or not the SD card is present and wire that to the Arduino. For the software it sounds like AdaFruit did some fixing of the SD library to include an SD.end() command which can be implemented to properly disengage and then re-establish communication with the SD card. If this does not work I need to find a work around using a RTC pretty quickly. The power DAQ needs to be done by the end of the week. I also need to order more microSD cards and need to register for Design Expo. I also made a diagram of what the Environment DAQ schematic should look like. Depending on Thomas’s success on getting a programmer for it and Mitch’s success on assembling it, we could be looking at starting the prototype of that this week. I have attached the schematic below.
This week I focused on finishing the power DAQ, notching 35 hours of enterprise work, and getting it deployed by our 2/4/24 deadline. I got the SD card issue fixed and solved a lot of grounding issues that were occurring with the voltage and current measurements. I also tested and debugged the final prototype and finalized the code. I then drew up the schematic for the power DAQ and began the manufacturing and box layout. We mostly built the boards out on perf board. We only had multistranded wires and not solid core which made the whole ordeal a little messier then preferred. I made a design for the cover of the boxes when I had a moment in there too. We unfortunately missed our deadline despite my best efforts and I was only able to get one box fully done and I have the second to about the halfway point. A tough end to tough week. I have attached some pictures of the week below.
Started to work towards midsemester goals. Trying to coordinate make up work to meet our missed deadline from last week, while keeping an eye on the road ahead. We have the environmental DAQ prototype started and it sounds like we have the KiCad files started for it as well. Would love to get a practice board laid up from the campus mill. I would like to have the prototype working and order prefab boards before break. We also have the CDR coming up and keeping our thumb on that is also in the back of my head. Next week I hoping to work on the prototype for the environmental DAQ, test out the STM programmer we just ordered, and get the our test PCB manufactured. If the KiCad files aren’t completed yet, I will hopefully get to look at those this weekend.
This week I spent time on doing the KiCad for environmental DAQ and sourcing parts for that (considering specs, packaging, etc.). I also looked at some small redesigns for more accurate measurements and for better user experience. I think we should run the I2C through a DAQ because I am nervous about using the boot pins as doubles for that and I think we should use a constant current source with RTD because I don’t think we will be able to generate an accurate enough reading using a voltage divider. Unfortunately, this may all be moot, because the DNR and CFRES were thinking we should be headed in a different direction. At the moment this puts the whole project up in the air and we are waiting to see if we need a drastic change in scope to meet their needs. This is not the greatest time with the CDR less than a week away and with graduation at about 9 weeks out, so everyone’s a little on edge with this whole project. Our timeline was tight already and now with delay and potential scope change/scope creep we could be in for a ride on the back half of the semester. With the general slowness of communication from the DNR and CFRES, I also worry about when this will be ironed out and how long we will be in no mans land. If we need to change directions, we need to pivot ASAP and rework our spec sheet preferably before the CDR. If we are not and we just need to encompass their new goals (they want a lot of emphasis on the cooling system, the control system for the cooling system, and power specs. This is opposite of what we thought was communicated to us last time we talked to them), we need everyday we can get to accomplish this plethora of goals before the end of the semester. I attached an image of the schematic I made this week (even though it may just be a pointless relic in the future).
This week was CDR week so I spent some time putting together the presentation for that and gave feedback to other groups. The biggest feedback we got from this was that our point of contact for this project has changed to a PhD candidate. We contacted him and honestly he seems to have much context for this project as we do. We’ll see if the communication in this project improves or if it continues to be the main issue of this project. In other news, we decided to just keep the environmental DAQ rolling and use it for temperature feedback in our control loop. The humidity aspect of it we are dropping completely which simplifies some things. To finalize the schematic I need Thomas to let me know which pins are needed for programming and for Ben to finish his RTD temperature test. I also need to experiment with the constant current source to properly size the current set resistor based off the bias current which I think is based on the voltage level. This will also determine whether or not current limiting resistors are needed on microcontroller inputs. I have attached images below. Not sure if the board file is perfect, might be some layout issues that I am not familiar with. Also used vias for the first time and not sure I did that in a perfect way.