During the work period from March 9 to March 23, significant progress was made on our team's project, primarily focusing on the electrical aspect, particularly transitioning to a permanent power supply and selecting a suitable microcontroller for the device.
In the first week, from March 9 to March 16, the team purchased a SmoTecQ 12V 2A Power Supply AC Adapter. With the new power supply, there was a significant reduction in weight and transportation concerns, which alleviated the physical validation issues since the device will be installed in the ceiling. There will be two cords powering the device: one cord connects to the power supply, which is spliced to provide power to the linear servo and the two fans, while the other cord connects via Mini-B USB to power the new microcontroller, the Arduino Nano.
Prototype (Left) vs Final (Right) Power Supply
Moving into the second week, from March 16 to March 23, the team opted to change the final microcontroller from an ATMega328 to an Arduino Nano. The ATMega328 required additional purchases of a custom PCB, capacitors, and resistors, whereas a team member had an Arduino Nano readily available. Conveniently, the Arduino Nano fit into the designated space originally intended for the ATMega328. Similar to the Arduino Uno, the Nano also features an ATMega328 microcontroller, but type P, which is a condensed version of the ATMega328, allows for placement on the final device. The Arduino Nano provided a 5V output to the IR receiver, a GND output to the IR receiver, a single signal input from the IR receiver, and three PWM signal inputs from the linear servo and two Noctua fans.
Prototype (Left) vs Final (Right) Microcontroller
Arduino Uno (Top) vs Arduino Nano (Bottom) - ATMega328 Size (Red Square) and General Size Comparison
Final Placement of Arduino Nano
All the electrical adjustment facilitates a physically easier validation process, which was scheduled to commence on March 18th. The team contacted Dr. Chen to borrow the anemometer. However, due to a conflict in the Experimental Methods Lab schedule, the anemometer cannot be borrowed. Consequently, the team decided to purchase the anemometer instead. As of March 24, we have all the necessary tools to begin the validation, but this setback means we're a bit behind schedule for starting Milestone 5 Tasks 1-5, which revolve around updating the final SolidWorks model and assembling the final device, which is mostly complete. Nevertheless, we're optimistic about catching up as we dive into the validation process next week.
The device working with new power supply and microcontroller: Video
Prototype (Top) vs Final (Bottom) Power Supply and Microcontroller Update
Between March 24 and April 6, our team aims to commence the validation process for our device, a critical phase detailed in Milestone 4 starting in the week of March 24. Here, Tasks 1-5 are on our agenda, with a special focus on collecting baseline data from the room, both pre-and post-device installation.
Moving on to Milestone 5 Tasks 1-4, where we are dedicated to refining the SolidWorks model and updating the microcontroller to ensure our design is current. During this phase, we will also determine which components from the tested design can be reused or require redesigning. This will be followed by the assembly of the main frame, vents, fans, and electrical components. The team has already placed an order for white filament to print the final mainframe for the device. Additionally, a PCB prototype board has been purchased, leaving only the task of soldering all the wiring and electrical components permanently.
Gnatt Chart: Milestone 4 and 5
By April 1, we aim to conduct another round of validation with the final version of the device.
The foremost milestone we're striving to hit is completing the validation setup. This has been a challenging task due to scheduling conflicts and the complexities involved in acquiring the necessary tools. However, now that we have the needed tools and our strategy laid out, we're looking forward to facing these challenges and meeting our objectives within this two-week timeframe.
Over the next two weeks, our team anticipates encountering minimal challenges in our project work.
A technical hurdle we are currently addressing is the placement of screw mounts, which must not interfere with the movement of the linear actuator. This approach is aimed at preventing any potential conflicts between the metal screws and the linear actuator. In the meantime, for our prototype, we will use screws with an unthreaded shank portion to ensure a tight fit against the ceiling and minimal friction should the actuator come into contact with the screws. Additionally, the team has shifted the position of the linear servo to prevent it from touching the linear servo’s path.
Linear Servo Shifted to Avoid Mounting Screw
Lastly, we're aware of the noise generated by the linear actuator during its operation. We're actively seeking online solutions and hope to find an effective fix within the next week. The team has also discovered that the linear servo produces noise even when unloaded, indicating that there may not be much that can be done to mitigate the noise if it persists under these conditions. Servo Unload with Static Noise: Video
The first video, the static noise could be heard also.
Comments