Safety

[Siti Vivi Octaviany]

Hi everyone,

I have some questions about micropilot.
I used MP2128LRC2 Heli Autopilot 900 MHz, and Tarot 650 as the vehicle.
We chose Quadrotor A as our mode.
My questions are:
1. Is it normal for all the motor to turn on briefly everytime we click the "Arm" button?
2. There is one time that the motor turn on when i click the "connect" button.
What's the trigger?
3. There is also a time that we accidentally switch the mode from the cic arcade to cic auto while in "disarm" position.
this made all the motor to turn on. and this time it didn't stop, until we switch the mode back to cic arcade.
Is there anything we did wrong? how to fix it?

We also have a MP2128G2 autopilot board. We would like to ask you what's the function of micro-USB port on the board?

Thank you

[Evan Schellenberg]

Hello Siti,

The LRC2 enclosed autopilots do not normally support 400hz PWM output so you should refrain from using them in a multirotor unless the standard 42Hz PWM frequency is  enough for your aircraft. Usually a much higher rate is needed for best performance of multirotors.

A multirotor capable non-enclosed autopilot (like the one with the USB port you have) will support 400hz PWM so those would be better to use.

With that said,

1. That is only normal if you have your throttle idle set high enough to make the motors spin, usually you want 0% idle throttle on electric aircraft though. The other possibility is you are in a manual mode and the throttle signal from the transmitter is high enough to spin the motors.

2. Connecting to Horizon in itself won't affect throttle. But depending on if the autopilot was already running commands from when you were using it before the GCS link failure pattern may have started and then ended when you connected so it would be running the commands you have in there.

3. This means that you likely don't have the armed safety settings turned on. In the FlightB tab of the VRS Editor enable the Armed Options for "Disable throttle/takeoff/off-ground until Armed" to prevent being able to start the throttle or fly until you arm the autopilot. When these are disabled you can fly manually without arming. Once they are set you won't be able to increase throttle even in manual modes if the autopilot is not armed.

Based on all of the above another common cause of rotors spinning incorrectly is when the servo zeros are set slightly too high. Make sure the zero pulse widths are set low enough that the motors will never start spinning until throttle is intentionally increased.

The USB port on the autopilot is only used for downloading datalogs. When you install Horizon it will also install a driver for the autopilot which creates a virtual COM port when the autopilot is connected to the computer via USB. This COM port can then be used to download the datalog through the Datalog Viewer.

You can still download datalogs over the RS-232 COM port, the 460kbps download speed will come close to the same download speed as the USB port.

Evan Schellenberg
MicroPilot Support

[Siti Vivi Octaviany]

Thank you very much for your response. I'll try to do as you suggest.