Bitcraze Forums

Hey all,

After some shoddy soldering, to my amazement my Crazyflie is fully functional and doing well. So far I'm able to get it off the ground, buzz around a few seconds, and crash it into things. This is a lot of fun, but I'd obviously like to do better. My question is around trimming values. There are two areas to trim them and I'm wondering if I understand this correctly. Do the values under "Basic Flight Control" pertain to the input device and the values under "Bootloader" pertain to the crazyflie itself? Am I safe to assume the bootloader values do not trim your input? My input seems to be calibrated just fine when testing the controls.
I've also noticed when fussing with the bootloader values, they swap when I reconnect the Crazyflie to validate them. That is the pitch value replaces the roll value and vice versa. That said, I'm not sure what's actually getting written to the Crazyflie. I'm using the latest firmware, and I see there was once an issue here: https://github.com/bitcraze/crazyflie-c ... issues/110 but has since been closed. I am using Linux Mint. Any ideas?

This week, I plan on trying out the Raspberry Pi image as well.

No replies to this yet so I guess I'll take a stab at it...

migzo wrote:After some shoddy soldering, to my amazement my Crazyflie is fully functional and doing well. So far I'm able to get it off the ground, buzz around a few seconds, and crash it into things. This is a lot of fun, but I'd obviously like to do better.

Congratulations!!! Practice makes perfect (both in soldering and flying).

migzo wrote:There are two areas to trim them and I'm wondering if I understand this correctly. Do the values under "Basic Flight Control" pertain to the input device and the values under "Bootloader" pertain to the crazyflie itself? Am I safe to assume the bootloader values do not trim your input? My input seems to be calibrated just fine when testing the controls.

Yes and no... Yes: The Flight Control tab values will trim the input as you expect. You can also configure your controller profile (or use a pre-configured one) to map trimming to buttons as well. The shoulder buttons are good ones to use. No: The "bootloader" values in the "Configuration Block" give you a way to "permanently" set the trim values in the Crazyflie firmware itself. So, yes they do trim your input and yes, they do pertain to the Crazyflie itself (as in they're written to the firmware).

migzo wrote:My input seems to be calibrated just fine when testing the controls.

In practice I have not needed to set trim at all. Alot has to do with if you balanced your propellers well and if you've gotten the battery centered. Though I'm sure there are cases where the you might need to trim values for optimal control.

migzo wrote:I've also noticed when fussing with the bootloader values, they swap when I reconnect the Crazyflie to validate them. That is the pitch value replaces the roll value and vice versa.

I have not noticed this but again, I haven't really had to set trim values and I don't know if I've ever set them in firmware. When you say you're using the latest firmware, is it the binary download or have you compiled it yourself from git master? Do the latter if you truly want the latest!!

migzo wrote:This week, I plan on trying out the Raspberry Pi image as well.

I really love using the Raspberry Pi for ground control. I've been using it for a few months and rarely ever use my laptop anymore (unless I'm trying to capture flight data). I've even added some tweaks to light a PiGlow when the cfheadless client is running and shutdown when I remove the controller. Soon I'll be setting up to use the PS3 controller via Bluetooth on RPi. Someday I'll write about these things on my Crazyflie blog.

The configuration block values are there to be able to correct for biased accelerometer readings. That can be caused by that the chip is not mounted totally flat or things such as tolerances within the chip itself. There might be a bug there though and the pitch and roll value might have been exchanged.

The trim values are there to account for the hole system which could be tilted motor mounts, etc. Often the trim values are enough to adjust.

A good test is to put the CF on a level surface and "rocket" it up in the air. If it goes strait up everything is well balanced.