A circuit that I made that takes a 5V signal and runs it through a Bubba Oscillator to turn that constant DC signal into a sine wave. This could be used for any AC motors or Solenoids that require AC power. I’m posting this here so that we would be able to use this during next season if needed. Multisim is best waifu, any other circuit design software packages are inferior >:-D
This is cool, but what would you use it for? Power pathways for motors or other actuators can’t be “active.” Plus there are no legal AC motors anyway.
He’s looking at using it for powering AC solenoids. Issue is that AC solenoids are implicitly not allowed, at least under last year’s game (and there’s very little reason for it to change for next year).
Under R32: “The only motors and actuators permitted on 2017 ROBOTS include the following:
…
Electrical solenoid actuators, no greater than 1 in. (nominal) stroke and rated electrical input power no greater than 10 watts (W) continuous duty at 12 volts (VDC)”
The specification of VDC is the issue here. Additionally, under R34 and R35, it’s illegal to use anything other than Spike relays and the PCM to power solenoids anyways.
Nice design, and I’d love to see if it works irl, but unfortunately not legal last year (and probably not this year either).
While not legal for Motors/solinoids, if amped up it could be used for a COTS computing device that needed AC
Couple of questions:
1> whats the voltage out, 5VAC?
2> whats the output current max?
3> Class A? Class B?
4> is there a ‘step’ at the zero crossing?
Interesting circuit for sure, however it won’t be able to power what you desire.
Op Amps are great devices, but their output current is extremely limited, less than 10-15mA for most models depending on a large array of factors. The use of resistors as a divider on the output line also contribute to a low output current.
I’ve replicated the first half of your circuit (for the sine wave) in another simulator here: https://goo.gl/Fqtqwj
You can see as you change the value of the artificial load resistor (the resistor connected to ground on the right), the current draw causes the voltage to drop to near 0. Using a resistor value of 1 ohm, you get voltage swings of +/- 3mV and current spikes of 3mA.
In inverters, high power components like mosfets are used to get an approximation, and then some capacitive (or maybe inductive, too) smoothing. There’s other components and types also, but I’ll leave that up to further reading
It is not clear what your purpose in posting this is.
Other than the low probability that something like this would be legal for the next season and the limitations of the devices used, it is unlikely that one would get something working quickly enough within the competition season unless one already had many years of experience designing inverters already. Even if someone got something running, there is a high chance that it produces enough interference as to prevent other parts of the robot (RoboRio, radio) or the FMS from working properly.
Even if the probability is low, it needs to be made public somewhere for it (or a modified version) to be used at competition, correct? That is what I gathered from his original post.
That is why I asked the OP why they posted this.
Based on past rules, and all the other issues pointed out by the other posters in this thread, it is highly unlikely that this will ever be used at competition (or even in the off-season). If one does not understand or appreciate what people have posted about why this will not work, then this thread becomes another “Final 2011 Drivetrain” or “Final 2018 Drivetrain” thread.