Week 7 - Journal

Ideation

Tell us about your assignment's idea for this week. Why do you care about this idea? What inspired you? (Please include images or links to sources of inspiration)

For this week’s assignment, I’m designing a Touchless Mini Waste Bin specifically for office desks. It’s a compact, smart bin that automatically opens its lid when your hand approaches — and includes a built-in sensor to detect when the bin is full. This ensures the bin doesn’t overflow and helps users manage waste more efficiently.

Tool Chain

Which software/machines/materials did you use in the assignment? Why?

Software

Materials

Electronics

Design/Preparation Process

Explain the design and/or preparation process of your assignment. How did you use the tool or software to design and/or prepare your assignment before fabrication/implementation?

Design the circuit using Tinker Cad

Programming Arduino (pseudocode):

I used the pseudocode below to think about the code logic

I developed the code on the Arduino IDE and tested the components

Code Explanation

This circuit and program together form a smart trash bin that opens automatically when approached and alerts when it needs to be emptied, while satisfying all the specified programming criteria.
The circuit's logic is:
- Ultrasonic sensor constantly measures how far a hand/object is from the bin.
- IR sensor monitors the trash level inside.
- The Arduino reads these two sensors into the dynamic variables distance and isFull.
- Using an if statement with logical AND, the Arduino decides whether to:
  - - Open the lid (servo sweeps open then closed), or Keep it shut.
    - When the bin is full (isFull == LOW), another if turns on the status LED and pulses the buzzer to alert the user.

Development/Implementation Process

Explain the development/implementation process of your assignment. How did you use the machine/tool to manufacture or implement the design of your assignment?

Preparing the cardboard, and choosing the right size to fit the desk.

Defining the components

The final product!

The final product! [VIDEO]

20250915_202808.mp4

Ultrasonic sensor constantly measures how far a hand/object is from the bin.

20250915_202636.mp4

Ultrasonic sensor constantly measures how far a hand/object is from the bin.

20250915_203012.mp4

IR sensor monitors the trash level inside. When the trash can if full, the LED will turn on, and the buzzer alerts the user.

Community of Learning

Did you ask for feedback? What are the ideas that others have contributed or suggested? What was someone else’s idea that you built upon? How did you help your peers? How did your peers help you?

At first, I was unsure whether to use an ultrasonic sensor or an IR sensor. Some online resources suggested ultrasonic sensors because they are accurate for measuring distance, but others noted that IR sensors have a faster response time and are simpler to integrate. Since my project only needed to detect the presence of a car rather than measure its distance, I chose the IR sensor. The quick response made it more suitable for opening and closing the gate without delay.

Reference

Overcoming Challenges

When you got stuck, what/who did you turn to? At what point did you have to pause to research or learn more before moving on? What are some mistakes, pitfalls, or challenges that others can avoid if they were doing this assignment?

The servo sweep—the gradual open/close of the lid—was a new concept for me when I started this project. At first, I simply wrote:

After experimenting and researching, I learned to move the servo in small angle steps with a short delay between them:

Final Project

How can you use the skills and knowledge that you've acquired this week in your final project?

The work with the smart bin gave me practice in more than just wiring sensors—it trained me to think about the overall logic and function of a device from start to finish. Working on the smart bin taught me how sensor signal noise can affect a project’s accuracy.

WOW!

What is the coolest thing that you've learned this week? What is something that you will never forget from this week?

Weekly Digest [OPTIONAL]

Tell us about any other cool things that you've made this week: in the Hands-on activity, tutorial examples, exercises, or any other cool mini-project that you tried out aside from the assignment.

Title of Media

Assignment Design Files

Code [INO]

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