Specialists of the Institute for Space Systems conducted successful tests of the perpetual motion machine in space. Valery Menshikov, the director of the institute, said that the machine was installed at Yubileiny satellite which was launched into orbit almost a year ago. The satellite can now move from one orbit to another with the help of the engine, which discharges no reaction mass.
The first tests were conducted in June and July of 2008. The tests revealed some problems that need further developments of the machine, but the orbital experiment was conducted successfully in general.
The new engine lasts for 15 years and can be started about 300,000 times. It uses solar batteries for its power, engineers at the institute said.
Some common ideas recur repeatedly in perpetual motion machine designs. Many ideas that continue to appear today were stated as early as 1670 by John Wilkins, Bishop of Chester and an official of the Royal Society. He outlined three potential sources of power for a perpetual motion machine, "Chymical Extractions", "Magnetical Virtues" and "the Natural Affection of Gravity".
The seemingly mysterious ability of magnets to influence motion at a distance without any apparent energy source has long appealed to inventors. One of the earliest examples of a system using magnets was proposed by Wilkins and has been widely copied since: it consists of a ramp with a magnet at the top, which pulled a metal ball up the ramp. Near the magnet was a small hole that was supposed to allow the ball to drop under the ramp and return to the bottom, where a flap allowed it to return to the top again. The device simply could not work: any magnet strong enough to pull the ball up the ramp would necessarily be too powerful to allow it to drop through the hole. Faced with this problem, more modern versions typically use a series of ramps and magnets, positioned so the ball is to be handed off from one magnet to another as it moves. The problem remains the same.
More generally, magnets can do no net work, although this was not understood until much later. A magnet can accelerate an object, like the metal ball of Wilkins' device, but this motion will always come to stop when the object reaches the magnet, releasing that work in some other form - typically its mechanical energy being turned into heat. In order for this motion to continue, the magnet would have to be moved, which would require energy.
Gravity also acts at a distance, without an apparent energy source. But to get energy out of a gravitational field (for instance, by dropping a heavy object, producing kinetic energy as it falls) you have to put energy in (for instance, by lifting the object up), and some energy is always dissipated in the process. A typical application of gravity in a perpetual motion machine is Bhaskara's wheel in the 12th century, whose key idea is itself a recurring theme, often called the overbalanced wheel: Moving weights are attached to a wheel in such a way that they fall to a position further from the wheel's center for one half of the wheel's rotation, and closer to the center for the other half. Since weights further from the center apply a greater torque, the result is (or would be, if such a device worked) that the wheel rotates forever. The moving weights may be hammers on pivoted arms, or rolling balls, or mercury in tubes; the principle is the same.