Know How...

Apr 9th 2015

Know How... 138

Towers Time Forgot, PID Settings, and Feedback

Microwave towers use to beam data!
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Learn about the Microwave Radio Relay Skyawy, RasOSMC is awesome, PID settings for your quadcopter, eBook reader that's not a Kindle, getting NAT'ed by your ISP, and a map of no drone fly drones. Let's talk PID P = "Proportional Gain Coefficient" * P addresses the algorithm responsible for balancing the input from the pilot with the data from the sensors. -- It "wants" to level the sensors -- A higher P setting makes the craft more reactive to angular change -- A lower P setting will make the craft most "sluggish" and less apt to "snap" back to level The takeway is that the higher your P setting, the more your FC will fight to keep the craft level. ** If your P is too high, you'll typically see oscilations in the craft as the controller constantly overcorrects its angle to level. I = "Integral Gain Coefficient" * I addresses the algorithm responsible for balancing the corrections from P... over time. - It wants to "spread out" the corrections that the P value is pushing through the FC - A higher I setting will stretch out the corrections from P over a longer period of time - A lower I setting will enact the P corrections quickly The takeway is that the higher the I settings, the more smoothly your craft will move * If your craft wobbles during descent, your I setting is too low * If your craft wobbles during punch-out, your I setting is too high. D = "Derivative Gain Coefficient" * D is the algorithm that softens the corrections from P - It wants to "smooth out" the corrections that the P value is pushing through the FC - At a higher setting, it will reduce the input the P value has on the FC as it gets closer to level The takeway is that we don't use D --- If you want acro: - High P - Low I - Increased D If you want smooth and stable: - Low P - High I - Less D The process for tuning is simple, but can take some time. 1. Set I & D to "0" (If you're using a KK, you don't have D settings) 2. Set P to 20 and fly the craft. 3. If it flies smoothly, increase P by 10 and fly the craft 4. Repeat step 3 until you start noticing high-frequency oscilations 5. Back off your P settings by 10. ** You now have your ideal P setting 6. Set I to 20 and fly the craft 7. Practice descent 8. If it wobbles, increase I - then repeat descent 9. Repeat step 8

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