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Showing posts from July, 2012

Motorized Balancing Toy

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Materials: • Annealed steel wire (bailing wire) • A hobby motor • About a 2' solid core copper wire (we like to use twisted pair telephone wire for this) • AA battery • Wide rubber band or inner tube slice • 1'' x 6'' wood dowel • Small piece of wood (1/2' x 4 x 4'') for a base • Small piece of foam core • Popsicle stick Tools: • Scissors • Pin nosed pliers • Small wood saw • Hot glue gun This project addresses two basic mechanics concepts, center of mass and torque. In order to get the toy to balance you have to find the center of mass of an asymmetric object, the motor wire and battery.  Because the toy is essentially a beam you're dealing with an issue of torque.  That is to say the twisting force on the toy will be equal to the weight of whatever is at the end of the wire (the motor or battery) and how far the motor or battery is from the balance point (the center of mass). When it comes to powering the toy, you also have

Scribbling Machines

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Materials: • Skewers • Dowels • Popsicle sticks • Clothes pins • Cups • Cardboard tubes • Pipe cleaners or wire • Masking tape • Rubber bands of various sizes • Straws • Hobby motor • Annealed steel wire • AA batteries • Hot Glue Gun Stick or Cork or Eraser (used as counter weight) Tools: • Hot glue gun • Wire cutters • Wire strippers Scribbling machines are simple drawing machines which use a small motor to move a pen or pens around a pad of paper to create interesting patterns.  The idea of scribbling machines is not a new one for  in our experimentations we've found that having a restricted pool of material to build with creates more interesting patterns and more importantly machines that are truly adjustable. Adjustability is valuable from a an educational perspective because it encourages iteration and an understanding of how changes in form effect changes in movement. The most important element of a scribbling machin

Sound Automata

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Sound automata is a modified automata mechanism designed to make a series of sounds instead of animate a scene or character. We've separated the material needed for the mechanism for the automata and the noise makers in order to make things clearer. While this a good starting place there is really no limitation on what material you can use especially on the sound making side. General materials for the automata mechanism: • A small bottle or large plastic cup • Foamcore or Cardboard • Skewers, chopsticks or 1/4'' dowel  • Straws: standard and jumbo • Popsicle sticks   Materials for making sound: • Annealed steel wire • Rubber bands, clothes pins (these make good springs if you need something to snap back) • Cups, cans and cardboard tubes (can be simply hit or have something stretched over them to make a drum, alternatively they can be cut into smaller pieces). • Bottle caps • Washers • Nails • Hot glue sticks Tools: • Scissors • Hot glu

Diving Board Automata

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Materials: -Foam core or cardboard -A plastic cup, or bottle -Jumbo straws -1/4'' dowel -Bamboo skewers -Material and accessaries to create the scene to be animated Tool: -Utility knife -Hot glue gun -Wire cutters/ pin nose pliers We made automata several different ways in the past and eventually settled on this one, which we call diving board automata. The main structure consists of some sort of container with a  piece of foam core sticking off the top like a diving board. The container can be a cup, yogurt container, soda bottle or any other shortish food containers which serves to hold the crank shaft. The diving board holds the mechanism and the scene to be animated. This is a distinct advantage over micro automata because the mechanism is easily accessible if it needs repair or adjustment.   First poke 2 holes in the bottle about 2/3 of the way up. Wood screws work well for this as you can use them to drill into the plastic  Op

Micro Automata

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Materials: • Wide clean plastic cup or clear solo cup. • A straw • Skewers • Bottle caps • Foam core • Tape Tools: • Scissors • Hot glue gun • A wood screw • Phillips screw driver or pencil Automata meaning self operating machine typically consisted of a clockwork statue or scene and were first created centuries ago in Europe and Asia.  They were in many ways the direct ancestor of what became electro mechanical robots.  For our purposes automata are a good way to explore machine's function of converting one form of energy and motion into another.  They are also a way to teach simple mechanical problem solving skills. Micro automata were the first in our series of attempts to simplify cardboard automata. The basic idea was to avoid building the box by putting the mechanism inside a clear plastic container.  Mechanically they are very simple. They have a input shaft with a crank coming out the side and an output shaft coming out the top with a mechanism in th

Mechanics Projects

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Mechanics is the science of motion and includes things like the science of falling and gravity, of mechanisms, of pressure and of aerodynamics. Sound is also technically included in this category though we've separated it for clarity.   We have a number of mechanics projects which we will share in the next batch of posts, but we wanted to take this opportunity to highlight some of great mechanics projects created by other institutions. Drawing Board: This is an Exploratorium Science Snack we particularly like, which records the pendulum motion of a suspended platform to create what is called a harmonogram. We sometimes call this a pendulum drawing machine, because the drawings it makes are a record of the motion of a pendulum swinging in 2 dimensions. The drawing created illustrates conservation of energy, the conversion of gravitational potential energy to kinetic and back again, which attempts to maintain the motion of the board and friction between the pen and paper, a