This house is heated by forced hot water. Natural gas is burned to heat the water stored in a loop that goes to the radiators in the house. When the thermostat recognizes that the room temperature has fallen below a set limit, a signal goes to the furnace, which turns on and heats the water. Heated water then flows through the pipes to the radiators. The radiators are heat exchangers, and transfer the heat into the air in the room. When the temperature at the thermostat reaches the preset level, the system stops sending hot water to the radiators.
One of the rooms in this house is equipped with radiant heat in the floor. Below the bricks, is a network of plastic tubing, which carries the hot water from the furnace. The heat is transferred out of the tubing, into the brick of the flooring, and then into the air of the room.
In this house, the hot water system uses a tank. Natural gas is burned to heat water, which sits in a tank until somebody turns on a faucet or appliance that demands hot water. The hot water then flows through the house’s pipes to the faucet, where it is used and then drained to the sewer system.
Our eyes help us to perceive three dimensional depth by having two visual sensors, separated by about 100mm of distance. This slight difference between the right and left eye is enough for us to see what is in front or behind the things we see. Since most cameras have only one lens, they show a two dimensional view of the scene.
Stereograms were invented during the early days of photography, and used two cameras, slightly offset, to show three dimensional scenes.
This project allows you to take two pictures with two cameras, and get the results of a 3D image. This rig was built with K’nex, but it can also be built with LEGO bricks, and can be made of 3D printed parts or even two cameras taped to a small board.
Some design considerations to keep in mind: the cameras need to be parallel to each other, the lenses need to line up side to side, and if your subject is moving, you need to keep care that you press both shutter buttons at the same time. Simultaneous shooting is less of a concern if you mount your rig on a stationary object, such as a tripod, and the subject doesn’t move.
Once you take the pictures, you can view them by showing each on the screen of the phones or cameras. Eventually, you will want to put the pictures on a computer and view them side by side. To do this effectively, you will want to bring the pictures into a photo editing software application, and paste the picture from the left camera next to the picture from the right.
To view the pictures, look at the two pictures side by side. You will need to cross your eyes slightly, until you see a middle image. The ‘third image’ in the middle is a combination of the left and right images, and you should be able to see that there is a front of the scene and a back. If your head is too close to the pictures, it will be difficult to cross your eyes enough.
Choosing the subject to photograph with this tool may take some practice. You want to have a good foreground and background of the image. You may also find that if the foreground of the subject is too close to the camera, the images don’t combine well.
Using some laser cut parts, along with a handful of machine screws and nuts, wire, conductive tape, and packaged inside a take out food tub, you can make a three axis motor controller.
Make a smartphone or tablet stylus from a scrap of fabric and some conductive thread. The design of your pen stylus can be adjusted quickly with this easy to do project. It should take only a few minutes to make the first one, which you can then test with your phone or tablet. With the feedback you get from testing, you can make another, test it and then make another.
Materials:
Fabric scraps
Needle and thread
Conductive thread
Tools:
Scissors
Process:
Sew a tube of fabric that will fit over the end of the pen.
If you use conductive thread, you won’t need traditional thread.
Sew a pad of conductive thread on the tip of the pen cover.
Make sure that the conductive thread is sewn so that it comes in contact with your finger. If you use a metal pen, you can make the conductive thread come in contact with the pen body.
Test it out to see how well it works.
Adjust the technique and process until the stylus works properly.
Wondering what you might find inside an old radio or boombox? In this video, I explain a bit about what the guts of a radio are. There is also a bit of discussion about the tools and techniques.
Taking apart devices that we use on a regular basis can provide a fascinating view of what things are and how they work.
Inside a radio, you can find lots of interesting things. You can take one apart to get at the useful components and systems, and you can learn a bit about how things are made and how they work.
Tools:
Safety glasses
Long, narrow Phillips head screwdriver
Flat/straight screwdriver
Pliers/wirecutters
Pen for marking parts
Supplies:
A radio boombox
Finding one or two boomboxes shouldn’t be too hard, but getting enough for a whole class to do this project will be a challenge. If you find them over a period of months, you should be able to accumulate a dozen or more. Getting the radios in this way can be effective, but hey will probably won’t be of the same model or brand.
Process:
Set up an area to work.
Everybody near this project should be wearing safety glasses.
Use a screwdriver to remove the screws holding the front to the back of the radio.
Carefully loosen the wires from the case.
Pay attention to how the switches on the outside control the circuit inside.
Check out the tape player mechanism, and cd player mechanism.
Identify each of the systems in the radio: amplifier, radio, tape mechanism, cd player, power source.
You can use the component systems inside the radio for other projects.
Save the parts in a way that will help you use them in the future.
The Mendocino Motor floats in its own magnetic field and converts light into electricity and magnetism, which are then converted into the motion of the motor.
Building and studying this project provides the satisfaction of creating an amazing bit of technology, and the opportunity to explore magnetism, electromagnetism, electric motors, solar power generation, and personal manufacturing.
Build the base that holds the magnets and provides a bearing point for the motor. Then wind the motor coils, and solder them to the solar cells. When the motor is assembled, you’ll balance it so it spins freely, and perform any troubleshooting to make it work properly.
He is demonstrating the laser cutter using a file that has four different line types, and cuts with both raster and vectors. The resulting little paper house has two depths of cuts in the vector, and two intensities of burns for the raster.
Using file cards and aluminum tape, you can make a sensor board that will be able to tell between different cards. By using individual cards, you can provide input to a light output board for a simple quiz game. You can also use this system to add input to an Arduino or other microcontroller circuit project. Connected to a Makey Makey, you can make a computer input based on placing the correct card on the sensor board.
You can experiment with electricity with just a few supplies, and some simple processes. By building your circuits on file cards, it is pretty easy to try out circuit ideas and see for yourself how they work.
Process:
Cut the aluminum tape in half lengthwise
Attach the tape to the cards so there is some overhang to the back of the card.
Clip the battery pack to a card.
Clip a second card to the first.
Tape an LED to the second card.
Orient the LED so that it lights up.
Substitute cards that have motors, light bulbs and other electrical components.
Build a card that has a gap on one of the rails. Use this to see what materials will conduct or insulate.
Conductors will allow the circuit to be completed. Insulators will not complete the circuit.
Make switches with a combination of conductors and insulators.
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