DIY磁悬浮玩具的做法2.doc

NEW LOWER PRICED, REVISED KIT HAS ADJUSTABLE CONTROL This simple electronic kit uses magnetic levitation to suspend small objects up to about 1/2 ounce (15 Grams) or so in mid air.? This is an ideal Science Project for ages 12 and up!? Detailed 6 page instructions include theory and clear images.? See below to order either the complete kit of parts, or fully assembled and tested versions. The air gap is about 3/8.? The electromagnet stabilizes the position of the suspended rare earth magnet(s) attached to the levitated object.? Feedback is provided by a linear Hall Effect sensor mounted under the electromagnet.? Once calibrated properly using the circuit board mounted control knob, suspended objects are stable after settling.? The knob is can be used to adjust the air gap by about 1/4. NOTE!? I am often asked if the design can be modified to lift more weight, or if the gap can be increased.? The answer is NO.? There are inherent limitations due to the size of the electromagnet and how quickly its field can be switched.? The most weight that can be lifted with this type of design is about 1 ounce (30 grams).? The air gap can be extended up to 1/2 (13mm) depending on weight. Getting an object in place is relatively easy. It is an eerie feeling when you offer the item up to the sweet spot as the controls grab the magnet - pulling it slightly into position.? It feels like some kind of science fiction force field.?? Objects set spinning will continue to spin for several minutes! If you dont see a video clip above, then click here to see it on YouTube. The kit as supplied has a limited range of weight that it can lift which is no more than .5 ounce including the magnets.? Items like a ping pong ball would be too light, and extra weight would need to be added inside like more magnets or small washers.? The design requires that the magnet be at the top of the suspended object to keep the magnet from flipping over. If power is turned off -- the magnet will drop away.?