From Squishy Circuits to Robotics Using play-dough to build and understanding of circuits
Inspiration Engineering in Our Daily Lives
Background Information beam.ucla.edu
Hands-On Experience with Circuits & Playdough Dont need to be an electrical engineer Dont need a soldering iron Dont need prototyping board Dont need circuit diagrams FUN FAMILIAR TOY SAFE EASY TO MANIPULATE
Start Squishy Circuits Activity with Introduction Conductors Insulators Resistors Closed Circuits Open Circuits Short Circuits Series Circuits Parallel Circuits
Conductive Playdough Conductor allows electricity to easily flow through it. Conductive dough contains salt. Conductive dough contains tap water. Salt (sodium chloride or NaCl) disassociates into sodium (Na+) and chlorine (Cl-) ions.
Insulators Do not let electricity flow through it easily Act like a wall to the electricity Electricity must go around the insulator If path is not available, circuit is incomplete Insulating dough does not use salt Uses distilled water No ions are available to allow electricity to flow
Resistance All materials have resistance Insulators have high resistance Conductors have low resistance Insulators act as walls Conductors act as roads
Closed Circuit Need a continuous path for electricity to flow from a power source (like a battery), through a conductor, into a device that uses power (like a lightbulb), and back through another conductor into the power source.
Open Circuits and Short Circuits
Series and Parallel Circuits Series circuits provide one path for electricity to flow. Parallel circuits provide multiple paths for electricity to flow.
Circuits 101 from Sparkfun
Gather Materials Flour Salt Cream of Tartar Vegetable Oil Food Coloring Sugar Deionized or Distilled Water Granulated (Powdered) Alum 9V Batteries Snap Connectors 10 mm LED assortment Tap Water Hot Plate or stove Non-stick Pan Plastic spatula Sturdy spoon
Make Dough Ahead of Time
Safety These activities are designed such that the dough is used to connect components. Never connect components, such as LEDs, directly to the battery pack, as running too much current through components can damage them, possibly causing them to overheat or pop. Follow standard electricity safety considerations.
Additional Tips Dont connect 9V battery directly to LEC, the LED may burn out or pop Dont mash two types of dough into each other. This makes it difficult to separate them for future classes The LED only works in one direction. This is called polarity. One leg of the LED is longer. This should be attached to the positive wire from the battery Dont cross the wires on the battery connectors- This will short out the battery! It may heat up and explode!!! Warn students about high voltages and high currents. Never stick wires or other objects into wall sockets!!!
EXTENSIONS Elenco Learn To Solder Kits Ladybug Soldering Robot Sew Electric
Learn to Solder Elenco Learn to Solder Kit is very complete Purchased desoldering pumps separately Purchased helping hands separately Sparkfun Tutorial
SewElectric.org Conductive Thread Needles Watch Batteries LED Lights Felt