The Planetary Weight Machine

The Planetary Weight Machine, used one’s weight as a comparative measure in an attempt to grasp and understand what the environments and gravity on the planets of the solar system would be like.

Simply standing on it displays one’s proportionate weight on all the different planets of the Solar System and the moon. Unfortunately Pluto had to be left out. An RFID based token system was also designed, to activate the printer which printed out each person’s weight as a souvenir to take back home.

I designed and built the Weight Machine in collaboration with the Indian Institute of Astrophysics and Indian Institute of Science. It was exhibited at the Jawaharlal Nehru Planetarium Bangalore, during the Kalpaneya Yatre 2010, commemorating the International Year of Astronomy.

Sandeep Mathew
Concept Development 
Processing Code
Arduino and Physical Computing
PCB Design
Industrial Design
Permanent Exhibit @ Jawaharlal Nehru
Planetarium, Bangalore

How it Works

Standing on Load Cell (A) provided the necessary input. The planetary weight measurement was then calculated by the Arduino Mega (B) and then displayed on the 7-segment displays (C). Further, If an RFID Token (D) was pushed through the coin slot in the Machine, the RFID Reader (E) would pick up its unique ID and a print out of all the weights would be made, to take home as a souvenir.


The form of the Weight Machine was inspired from the arcade game and the token system was identical to the slot to put in the coin. It was finally exhibited at The Kalpaneya Yatre Festival, which ran from November 26th 2010 to December 5th 2010 with nearly 8000 visitors daily.


Weight, being such an commonplace and relatable measure, became a unit of imagination, and laughter. The children who interacted with it especially found it wondrous and absurd that one could weigh a mere 18 kilos on Mercury and 126 Kilos on Jupiter!