As previously outlined in Blog 5, the objective from February 4 to February 17 was to finalize the prototype for testing, focusing primarily on mounting the fans, fan brackets, and the linear servo, while addressing potential vibration concerns.
The team successfully affixed the fan to the mainframe to mitigate any potential vibration issues. To our surprise, the 3D-printed fan bracket surpassed expectations, as it was initially intended for replacement with an aluminum L bracket in the final design. After running the fan at full power and speed, the device showed no signs of vibration issues. As a result, the team decided to continue with the 3D-printed frame to save on weight, cost, and manufacturing time.
3D Printed Fan Bracket and Fan bolted on Main Frame
The team was taken aback to find that the fan was receiving inadequate amperage, causing its labeled "100%" power to operate at only 50%. However, testing with the power supply revealed that the fans, wired in parallel, required 0.2 Amps. This revelation wasn't worrisome as it remained under the servo's stall current of 0.33 amps.
Additionally, the team conducted functionality tests to ensure that each component performed its intended task. The servo smoothly closed and opened the vents, although concerns arose regarding mounting it onto the 3D printed frame, fearing potential material flexing. Consequently, the team may choose to mount the servo onto the actual aluminum frame if needed. Unfortunately, due to complications with 3D printing, the team has been unable to perform this test to assess whether the frame flexes.
Functionality Test: (Shows no vibration exhibited from device and components works as intended)
To complete milestone 3, we'll mount the servo on the 3D-printed main frame or the aluminum frame and adjust its position in the code, enabling us to progress to milestone 4. As the Arduino is only temporary for validation, it will be mounted externally.
For milestone 4, we'll begin validating the prototype. A crucial aspect is ensuring consistent readings from the anemometer. To achieve this, we'll design a cradle for the anemometer to rest in, facilitating average air velocity measurements. In preparation for validation, we'll ensure we acquire the necessary tools such as the decibel reader, thermometer, and anemometer, which are borrowed from Dr. Chen's Experimental Methods Course.
Desired Location of Anemometer
The validation occurs in team members' rooms, ensuring accessibility and scheduling won't be problematic. However, adjusting the rooms to 100 CFM is necessary prep work which can be easily completed by adjusting the damper of the room. Installation is a straightforward swap, as that was also the selling point of our device. It will be connected to the power supply currently used for coding purposes.
Milestone 4 offers a chance to identify any needed tweaks or adjustments since it's utilized as intended in an actual room.
Gannt Chart 4
Gannt Chart 3
One of the issues the team foresees is the 3D printing of the large prototype pieces for the vent device casing and the large-sized fan mounts. The reason for this is the limiting size of the 3D print bed for the 3D printer we have at the moment. The current print bed size for our printer is the Ender 3 with a max print volume of 220mm x 220mm x 250mm (8.66in.x8.66in.x9.84in.) which is not large enough for the large vent casing which will be approximately 14 inches long.
While printing the second half of the frame, we encountered an issue with warping at the corners. However, the team understands that achieving a perfect print may require more than one attempt. The error could've been due to not having enough adhesive on the printing bed or accidentally shifting the base of the 3D print. However, during the next run, we will observe the process to ensure a successful outcome.
Failed 3D Printed Piece (Left) and Accidently Broken Frame (Right)
As seen in the picture below the prototype parts are made in smaller pieces to fit the 3D printer volume. Certainly, using a larger 3D printer like the ones available through the ASME lounge could indeed offer a solution to our problems. Not only are these printers larger, but they're also better in terms of their capabilities and quality of output. This upgrade in technology could significantly enhance our ability to produce large pieces efficiently and effectively. In any case, the prints can also be printed in the diagonal direction across the volume of the print bed to accommodate for lengths that cannot be done lying flat on the X or Y plane.
Rough Draft of Mainframe Placement
Comments