For all your walking on the ceiling needs, see Hackaday: http://hackaday.com/2014/05/23/electromagnetic-boots-for-all-your-upside-down-needs/
The craftsmanship seems to be at a high level, although I am not trained in the use of power tools. But all the pieces fit neatly together and the all the connections are tidy, just like a good piece of clothing. I like
watching craftspeople at work. I might need some ceiling walking in my training exercises.
Here's the main making-of video from the Hackaday site:
As Oersted, Ampere, and Maxwell said
\[ \nabla \times \mathbf{B} = \frac{4\pi}{c}\mathbf{J} +\frac{1}{c} \frac{\partial \mathbf{E}}{\partial t} \]
That is, the magnetic field B generated around a wire (the curl \(\nabla \times \mathbf{B} \)) is proportional to the sum of the current density J and to the change in time of the electric field E! This equation encapsulates a whole boatload of exciting math, as well as being almost unbelievably beautiful and tidy! We have no a priori reason to believe that the universe is (sometimes) so tidy, but sometimes it is. Oh, and if you have enough J you can walk on the ceiling! (The \(\partial \mathbf{E}/\partial t \) effect is usually pretty small compared to gravity on Earth.)
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