The globe must have asymmetrical mass distribution - when left just levitating it always stops in the same position. My idea was to sync my intermittent magnetic pulses with this gravitational self-rotation. In other words I wanted to give rotation momentum extra energy to overcome this resting point. The coil sits in the middle pointing at the equator - no special position. Globe wants to rotate anti-clockwise - I am guessing it has something to do with how I have chosen the point when the coil is activated vs its asymmetrical mass and magnetic material inside the globe. When I spin it clockwise it slows down and eventually changes direction to anticlockwise after a few minutes. Not sure I know the Coriolis effect...
@@zadzwon112 The Coriolis effect results from the Earth's rotation. It causes hurricanes to spin counter-clockwise in the northern hemisphere but cyclones to spin clockwise in the southern. Your globe may spin clockwise in Australia?! Time to schedule a trip (for science). You may enjoy these other spinning globe mechanisms: ua-cam.com/video/U-NII1RdlcQ/v-deo.html.
You dont need a comparator. Pin 2 of the 555 is already connected to a comparator input inside the timer chip. There's no constraint on rise/fall time.
Thank you - I could connect light sensing directly with pins 2 and 6 of 555 indeed. But as I had LM339 for temp sensing anyway with another 3 free comparators onboard and it worked for me before I went for it. But good advice!
Is the drive coil slightly off center to favor a counter-clockwise spin? Or, is it a Coriolis effect? Can you maintain a clockwise spin?
The globe must have asymmetrical mass distribution - when left just levitating it always stops in the same position. My idea was to sync my intermittent magnetic pulses with this gravitational self-rotation. In other words I wanted to give rotation momentum extra energy to overcome this resting point. The coil sits in the middle pointing at the equator - no special position. Globe wants to rotate anti-clockwise - I am guessing it has something to do with how I have chosen the point when the coil is activated vs its asymmetrical mass and magnetic material inside the globe. When I spin it clockwise it slows down and eventually changes direction to anticlockwise after a few minutes.
Not sure I know the Coriolis effect...
@@zadzwon112 The Coriolis effect results from the Earth's rotation. It causes hurricanes to spin counter-clockwise in the northern hemisphere but cyclones to spin clockwise in the southern. Your globe may spin clockwise in Australia?! Time to schedule a trip (for science). You may enjoy these other spinning globe mechanisms: ua-cam.com/video/U-NII1RdlcQ/v-deo.html.
You dont need a comparator. Pin 2 of the 555 is already connected to a comparator input inside the timer chip. There's no constraint on rise/fall time.
Thank you - I could connect light sensing directly with pins 2 and 6 of 555 indeed. But as I had LM339 for temp sensing anyway with another 3 free comparators onboard and it worked for me before I went for it. But good advice!