Has anyone seen Lasersabers new motor runs on 1000uf cap

[conradelektro]

First tests with the biasing magnet behind the reed switch:

It is difficult to adjust the biasing magnet, but once I succeeded I got a dramatic reduction of power consumption down to a few µA (rotor still turning slowly consistently). The Voltage on the very weak AAA battery went up because the power draw dropped so much (may be a hundred fold).

Because it is so very difficult to adjust biasing magnet and Reed switch (relative position to each other and relative position of both to the rotor; too many variables), it seems easier to build an adjustable double reed switch, which I will do tomorrow.

So, I have very strong indication that "ON-time of the Reed switch" is the miracle behind Lasersaber's below 1 µA power draw. May be Lasersaber's Reed switch behaves differently than my model (which likes to stay in the ON state when close to the rotor and does nothing when moved away too far, a very narrow operating range distance wise)?

I have to learn a lot about Reed switches before I get this right! I also just realized that I never tried to position the reed switch above the rotor, I always had it next to it. So many things to do wrong!

Greetings, Conrad

[lasersaber]

@conradelektro


Yes, the reed switch makes a huge difference.


This "How to Prepare a Reed Switch for a Pulse Motor" video might help: https://www.youtube.com/watch?v=5XfkejxtLgQ


Another video that might be helpful:  https://www.youtube.com/watch?v=WAPeC1JcZkI

[conradelektro]

@conradelektro


Yes, the reed switch makes a huge difference.


This "How to Prepare a Reed Switch for a Pulse Motor" video might help: https://www.youtube.com/watch?v=5XfkejxtLgQ


Another video that might be helpful:  https://www.youtube.com/watch?v=WAPeC1JcZkI

Yes, that helps, thank you very much.

Greetings, Conrad

[conradelektro]

I used a new Reed switch and also tried two Reed switches, but making the ON-time of the Reed switch shorter does not reduce power draw significantly.

The only way to reduce power draw (to e.g. a few µA) is to introduce a resistance into the circuit. Lasersaber does it with a diode and the reverse current of the diode is enough to drive his little motors.

My motor is mechanically inferior to Lasersaber's motors therefore I need at least "200 µA at 1 Volt pulses" through the coils to overcome all mechanical hurdles.

In order to use the same circuit as Lasersaber I have to place a 5.6 K resistor parallel to the diode. This resistor then allows for enough current to drive the rotor slowly at 1 V supply Voltage. It simulates a diode with a 5.6 K reverse resistance (about 200 µA at 1 Volt). Gyulasun, thank you for the idea.

I can then do the same as Lasersaber with his motors, namely speeding up the rotor by blowing air over it, which charges the 1000 µF capacitor quickly to about 6 Volt, and it then rather quickly discharges moving the rotor. The rotor stops when the charge in the cap is lower than 1 V. I can not reach more than a few 100 rpm, therefore I only reach about 6 Volt over the cap. Lasersaber can spin it up his motors to a few 1000 rpm and reaches therefore up to a 100 Volt over the cap.

I can of course drive the rotor by providing at least 1 V over the cap (e.g. with a battery or a power supply).

Conclusion: I replicated Lasersabers experiments but not in a very impressive way, because my motor needs at least "200 µA at 1 V pulses" to move the rotor. Lasersaber's precise mechanical setup allows him to drive the rotor with a few µA. He also seems to use bigger magnets and more windings on his coils. Important is also a precise alignment of coils and magnets and a narrow gap between coils and magnets, which is particularly bad in my build.

A different question is average "power draw". When my motor turns very slowly with a 1 Volt power supply, average power draw is well below 200 µA. It is difficult to measure because the Multimeter jumps between meaningless Values. I have to try measurements with a scope (over a shunt, e.g. over the 5.6 K resistor).

Greetings, Conrad

[lasersaber]

The only way to reduce power draw (to e.g. a few µA) is to introduce a resistance into the circuit. Lasersaber does it with a diode and the reverse current of the diode is enough to drive his little motors.

Actually the 1uA motor in this first video had no diode in use.  See: http://youtu.be/Esphle_MsXI  The resistance comes from the 42 AGW wire itself.  At anything under 5V I would use no diode at all and tune for the lowest possible uA current draw.  Once you have achieved a current draw under 5uA with no diode then start experimenting with diodes.


I am also interested in hooking up one of these motors in an Adams motor configuration.   I also want to try using large flat 1.5" X 1/16" magnets with large thin pancake coils. I have so many ideas and so little time.