Failure to Launch

[Barkingspider]

Help!

FC: HK_MultiWii_328P
Motor: DYS 1806-2300kV
ESC: HK Blue 12A Flashed w/ SimonK

This quad has flown before...did a frame swap. Was running MW2.3. On a test flight before buttoning up the frame, it takes about 50% throttle to achieve any lift (props begin spin at ~5%)...and it immediately flips over. First off, my motors are spinning correct, and the props are as well. The ESCs have been calibrated. Before enough thrust is given to launch, I can give it forward, and it leans forward, and so on for each direction and yaw, so I know these are good; however, as soon as it leaves the ground I lose all control and it flips. I have moved from MW2.2, 2.3, 2.4 clearing EEPROM each time. I have Angle and Baro on switches, but they are off for this testing. I have tried new batteries, new props, new motors, new Rx, new Tx. I have my subtrim and endpoints set correctly. I am at a loss...HELP!

MultiWiiConf

Quad Pic

[JoacimW]

Hey
What size is the Quad? It looks like 4-5 inch propps.
Is the PID default? Have you done a PID tuning?
Every new setup needs to be tuned.
It looks to me the PID are off. P for ROLL and PITCH are to high. Set P to about 2.2
Do you have right settings in sketch?
#define QUADX
#define MINTHROTTLE 1064
#define HK_MultiWii_328P
Set Gyro filters.
In multiwii 2.2 - #define ITG3200_LPF_42HZ.
In multiwii 2.4 - #define GYRO_LPF_42HZ.
Read the sketch you find more info about the gyro filters.
Try this and then do a PID tuning. Do the tuning with level off.
Here is a very good video about PID tuning. It is in French, but has Eng subs.
https://www.youtube.com/watch?v=OeQI49U ... LA&index=2
They start with PID for Roll and PITCH at 15, that is way to high for your quad. Set it to about 3 or start with 3.3.
Take your time on the tuning don't stress it.
I can recommend a bluetooth adapter. It is much easier to tune with your mobile phone and you don't need to go back to your computer to make a new setting.
http://hobbyking.com/hobbyking/store/__ ... ouse_.html

About that it takes 50% throttle to achieve any lift.
Think about it, the frame take away alot of thrust. Less frame that are in the way, less throttle to lift, less vibrations on the frame and easier to tune.
Good luck.

[Kbev5709]

I have to wonder about the aerodynamics of that frame design. It looks like huge amounts of thrust are being re-directed straight out at a 90 degree angle to the normal thrust direction. The way those booms are designed they look like guards made to prevent too much lift. Those little props look like they spend half their time spinning over obstacles to airflow. Is that your own design? If so you really should rethink those booms. I can understand the issue if it is a first time one off original, trial and error and everything, but, I hope you didn't buy that from a manufacturer for a lot of money. I would never buy a frame with those obstacles to airflow for motor mounts. Just my 2 cents.

[Barkingspider]

Hey
What size is the Quad? It looks like 4-5 inch propps.
Is the PID default? Have you done a PID tuning?
Every new setup needs to be tuned.
It looks to me the PID are off. P for ROLL and PITCH are to high. Set P to about 2.2
Do you have right settings in sketch?
#define QUADX
#define MINTHROTTLE 1064
#define HK_MultiWii_328P
Set Gyro filters.
In multiwii 2.2 - #define ITG3200_LPF_42HZ.
In multiwii 2.4 - #define GYRO_LPF_42HZ.
Read the sketch you find more info about the gyro filters.
Try this and then do a PID tuning. Do the tuning with level off.
Here is a very good video about PID tuning. It is in French, but has Eng subs.
https://www.youtube.com/watch?v=OeQI49U ... LA&index=2
They start with PID for Roll and PITCH at 15, that is way to high for your quad. Set it to about 3 or start with 3.3.
Take your time on the tuning don't stress it.
I can recommend a bluetooth adapter. It is much easier to tune with your mobile phone and you don't need to go back to your computer to make a new setting.
http://hobbyking.com/hobbyking/store/__ ... ouse_.html

About that it takes 50% throttle to achieve any lift.
Think about it, the frame take away alot of thrust. Less frame that are in the way, less throttle to lift, less vibrations on the frame and easier to tune.
Good luck.

Sorry for the long delay, my sweetheart won't let me play with my toys on the weekends haha.

It is a 250 w/ 5030s. I have not done a PID tuning, I usually do that after getting it in the air and having a few flights with my tweaks. With that in mind, I tried your idea of moving the P to 2.2, and a general tweaking to some of my norms.
As far as my sketch goes, I have all the same things you said, except I am using #define GYRO_LPF_256HZ (default); however, I tried switching to your suggestion.

As far as the frame, I have flown this frame many times, and 50% throttle is super weak. I have another that LAUNCHES at 10%. I don't necessarily "race" with these things, but I do some pretty quick FPV stuff. The frame is more for durability to be honest...this is my dads model I built for him, and he needs to survive more than haul ass (hence the baro and angle modes - although to be clear, they are off during these tests).

I really appreciate the suggestions, but they didn't help (keep them coming!!) I am going to swap FC to a NAZE32 I have laying around to eliminate that part. I'll report my findings...I'm actually hoping it's something hardware, because I really like this board for my dad.

Thanks!

[Barkingspider]

Ok, swapped out the FC. I am now able to take off without flipping, had a bad battery for the throttle issue...it has been disposed of. I really want to keep the MultiWii on this quad. It is a software issue, I am able to fly flawlessly with the Naze32. Any other ideas? I cant upload my config.h due to character/file constraints, but I can sent it to anyone if that will help?

Thanks!!

[JoacimW]

Here are some other guys having problem with that FC.
http://multirotorforums.com/threads/mul ... lem.17274/