Weighing Bag

 Material List

(1)Conductive thread

(1)Crochet hook


(3)Alligator clips

(1)Button battery


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For more detailed tutorials of crochet, please see https://www.thesprucecrafts.com/how-to-crochet-for-beginners-979092

Circuit Diagram



Wristband by Wanqing Liu



Description and Discussion

Smart wristbands are popular in smart device market. They can provide testing and statistics of step counting, sleep, heart rate, and exercise data to users. In this assignment, I would like to build up a lo-fi prototype of a smart band, using the functions of circuit playground express.

The prototype is consisting of a band and a circuit playground express. The band is made by straps and cotton cloth. And the circuit playground express can be placed into the little cloth pocket, as well as remove from it. Methods used is sewing and coding.

This wristband is designed to monitor temperature and wake up user in the morning.

(1)By pressing the button A, user can switch on its colorful lights whose amount shows how high the temperature is (More lights represents higher temperature). If the temperature becomes higher than 36℃, all the lights will turn red, to remind user of paying attention to take measure from getting sunstroke.

(2)When the wristband prototype detect sunlight, it will play music to wake up user.

Why is twist? According to Clint Zeagler, wearable devices should avoid obstructing body movement. Twist, as is usually a place for watch, is ideal for light-weighted wearable devices and not stop people from moving.

I am new to coding, so I used MakeCode to make things easier. Codes were written by selecting and moving different modules. I have experienced some confused moment but finally I made it. What I learned from this assignment is basic knowledge of how to control my circuit playground express by code, and code logic.

Demo Video


Detail Image

I used a power bank to work as battery for powering the circuit.





Parts and materials

(2) Straps

(1) Cotton cloth

(1) Buckle

(1) Circuit playground express

(1) Power bank




The first one is the beautiful one. Second skin watch, designed by Svetlana Blum, is made in PU, LED and metal. There are two rows of LED lights in the watch, one displaying hours and the other minutes, to shows the exact time every five minutes. All the user need to do is touch the display to awaken the lights. Its shape has a sense of line, is full of classy vibe. The combination of the position of LEDs and the overall shape is just right, thus brings out the best for each other. My prototype is inspired by its use of LEDs.


The second one is not a light device but I like its inclusive function. People who visually impaired may have difficulty using common watch to look at the time. And Dot watch is a solution for this situation. It is a braille smartwatch and its users can read the time by touching its surface. It can also be connected to smartphone via an app. When someone call in, the Dot watch will display the name of the caller, then users can receive messages with ease by touching it. In my opinion, this is a useful and inclusive design, because it has well addressed the problem and is concise in appearance and simple to use.


The last one is a fitness tracker, the Atlas Wristband. The Atlas Wristband is made to monitor exercises, reps, calculates calories burned and evaluates form. What makes it different is users can see how each movement affects their body, and this wristband can track body on the x-, y- and z-axes. I also like the way that it align one edge of the rectangle to the strap’s, but I think its display interface is lack of aesthetic and a bit too large for a person who is doing exercise to carry.



Design Buzz. LED Display Turns the ‘Second Skin’ Wristwatch Into a Fashion Accessory[Blog post]. Retrived fom https://www.aminimalstudio.com/second-skin-watch

Dot Incorporation(2018). Dot Watch. Retrived from https://buy.dotincorp.com/product/dot-watch/?gclid=EAIaIQobChMIiqTs9JG77gIVVTizAB2Vyw-5EAYYASABEgIWNPD_BwE

Peter Li(2014). The Atlas Wristband. Retrived from https://www.indiegogo.com/projects/the-atlas-wristband#/

another work

Just make for fun! I sewed a seven-color led to a glove, and it can be powered by a button battery.

Video link: https://youtu.be/2ZYz3WpLMAQ

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