Product design with fun in mind


Personal endeavor , focused on adult users


Solo designer researching adult approach to design, kinetic mechanisms. basic circuits and sustainability through play


How might I design a desirable and fun experience through a sustainable toy


Theo Jansen’s quote “ The walls between art and engineering exist only in our minds” has been a motto for me ever since I encountered his Strandbeest exhibition. Research on his kinetic mechanism incited me to make a moving beast of my own.

Theo the horse is a moving toy that runs on solar energy captured by a photovoltaic cell that charges a storage capacitor, so that when enough energy is accumulated, the motor is powered. This is how a simple “Solar engine” works; its vantage point is being able to give out mechanical energy even when not in direct contact with light.


The system uses a CSS555 Integrated Circuit: a micropower timer that functions well even in low-light environments because it only needs 1.2 V to work. A photodiode is integrated as well, to maintain a constant voltage source on a fixed lighting level, in this case a 1.2V LED was used. As well, a 1K resistance to limit to current up to transistor, which when turned on, powers the motor. Being a lightweight object, this is more than enough to make Theo intermittently walk.

This is the basic circuit and Pin configuration:




SC= Solar Cell SC-2422

PD= Photodiode (1.2V LED)

CSS555= IC Timer

QP =Transistor (ZVNL110A Mosfet)

RB= 1K resistor

Cs= 0.1F Storage capacitor

M= Low current motor 4V, 10Ω

Theo’s physical mechanism was drawn in Autodesk Inventor™, exported to .dwg format and finally laser cutted on wood. One of the problems I encountered was Theo’s stability.