Devan – Arduino and CAD End Project

My Design

To add on to the bionic aesthetic, a non-movable hand temperature reader attachment was designed that can also be attached to the arm. The pointer finger would contain a temperature sensor and the back of the hand would contain an LCD screen displaying the temperature in Fahrenheit and Celsius. Additionally, the front of the hand would contain RGB lights with a ping-pong ball diffuser that would light up certain colors according to certain temperature ranges. All of the components would be housed inside of the hand. Overall, this feature adds to the bionic/robotic aesthetic that the artist was pursuing as it allows the user to know the current temperature just by looking at their hand. The lights additionally add an android-like feel to the overall design. The design features:

  • a removable cap to access electronics with hole for LCD screen
  • a hollow interior for electronic housing
  • a hollow pointer finger and hole for temperature sensor
  • a hole for ping-pong ball diffuser and lights
  • a threaded hole to attach to arm
How it was Achieved

Firstly, the LCD screen was wired to the Arduino board and potentiometer. A 330 ohm resistor was used to for the power connection. Next, the temperature sensor was added and analog pin was connected to the board to input voltage values. The sensor and its wires would run through a hole on the pointer finger of the hand. Lastly, four RGB lights were added in series with three 1000 ohm resistors for each color pin. The pin for each color was wired to different pins on the Arduino board. These lights would be hidden behind the ping-pong ball diffuser on the hand.

Code Explanation:

  • Section 2 – 9
    • Sets the input and output pins for the lights, LCD, and temperature sensor. 
    • Declares the variables as floats and the input values as integers.
  • Section 11-26: void setup 
    • Size of the LCD screen was declared and the serial.begin function was used to extract the temperature in real time. 
    • The temperature was set as an input and the lights were set up as outputs. 
    • The voltage value is read and is multiplied by 5/1024, where 5 is the maximum possible voltage and 1024 is the number of possible values 
  • Section 32-37: void turnOff
    • The code returns to this section later on when the RGB lights are needed off
  • Section 38- 72: void loop
    • Voltage is measured from the analog pin, then converted to millivolts, then converted to degrees Celsius, then converted to degrees Fahrenheit.
    • LCD screen is set to display “Temperature is:” along with the temperature values in Celsius and Fahrenheit. Every second the temperature is updated
    • If the temperature is less than 40 degrees Fahrenheit, the RGB lights are set to first turn off, then light up blue .
    • If the temperature is between 40 and 80 degrees Fahrenheit, the RGB lights are set to first turn off, then light up green.
    •  If the temperature is above 80 degrees Fahrenheit, the RGB lights are set to first turn off, then light up red.
Actual Circuit

The actual circuit displayed the proper temperature of about 63 degrees Fahrenheit and properly lit up green since the temperature was between 40 and 80 degree Fahrenheit. However, only one RGB light was used due to material limitations and the LCD screen was also directly connected to the breadboard due to wire limitations, causing some wires to be rearranged

Video explaining circuit