Today we present a complete build and configuration guide for a full acro Tiny Whoop build using the Beebrain flight controller. This build focuses on high performance flight via an FrSky or Spektrum transmitter. The Beebrain flight controller gives you native support for these protocols and full configuration via Betaflight.
Before we begin, I'd like to point out a few things about the build. This build is designed to be a fun project that ends with a high performance whoop.
The parts list we've gathered is a quality and easy to find set of parts. This guide will give you a great starting point if you want to tweak or change any part of your build. Controller Craft may earn a commission for order placed through these links. This helps support the effort that goes into making these guides and these are products we've used and like.
Total Aircraft Cost: ~$113
If you don't have a battery charger, you'll need:
The Eachine E010 frame is nearly identical to the Inductrix frame, with a couple minor differences. The back screw on the mounting pattern doesn't fit the standard square pattern. The battery compartment also doesn't natively hold the long, skinny 1s LiPo batteries we will be using. The E010 frame just needs a couple small mods to adjust for this:
Now the foam battery holder fits.
Since the Beebrain runs Betaflight, we are going to install the motors just as we would on any other racing quad. This is actually backwards from the original Inductrix motor configuration. For Chaoli CL-0615 motors, the Black/White wires rotate counter clockwise and Red/Blue wires rotate clockwise. Install the motors so that as you look down at the top frame from the top, the motor direction is as follows. This is the standard motor direction configuration for Cleanflight/Betaflight:
Run the motor wires through the mounting holes to the center of the frame. Push the motors straight into the mounts until they stop near the bottom. Be sure to push against the bottom of the motor mount. You can break the frame if you're pushing against the prop guards or supports. Then run the connectors up through the 4 openings on either side of the battery compartment.
Last, grab the Beebrain flight controller make sure to match the front of the board with the front of the frame. On the bottom of the Beebrain, there is an arrow pointing forward. The front of the frame has the mounting point, the back will not have a mounting point as we cut it in the previous step. Once the FC is aligned, plug the motors into the matching connector.
The Beebrain comes with 4 rubber grommets and 4 mounting screws. Grab 3 of each. Push the rubber stoppers onto the front, left, and right mounting points. Then grab a 3D printed camera / VTX mount and place it on top. Carefully screw these 3 points into the frame.
As you're mounting the flight controller, be sure the battery pigtail comes out the bottom. At this point tuck the motor wires into the tabs below each fan duct. Tuck the excess motor wire in a stack on either side of the battery compartment. Now you can see why we chopped the back support as we have direct access to the USB port on the board from below.
The FXT FX798 and FX797 seriese cameras come in a case that we need to remove. The camera mount will only fit the camera once the case is removed. There are two tabs on either side of the case. Pull those tabs out.
Keep the lens cap on while you push down on those tabs on a flat surface. The case should pop and loosen.
Take the lens cap off and pull the case off the front of the camera.
Now place the camera in the mount and measure the wire length to meet the top of the battery lead terminals where we will solder them. Cut the wires so they can easily reach the terminals without too much excess slack.
Tin the ends of these leads and solder them to the ground / vin pads on the top of the Beebrain.
Last, secure the camera using a standard rubber band. There are two pegs on either side of the frame that you can use. I like to use a long enough band that it wraps all the way around the frame. This keeps the motor wires tucked away and adds some more support for the battery. Also take this time to carefully push the propellers onto the motor pegs. Be sure to push firmly straight down.
That wraps the build portion of the Beebrain Acro Tiny Whoop. Now on to the configuration of Betaflight and your radio transmitter.
We will be walking through a full setup and configuration which should give you a general direction to head. If you get lost or have specific questions we don't cover here, refer to the BeeBrain manual which can be found here via Dropbox.
Before we get started with the configuration, I like to upgrade the flight controller to the latest firmware. Start by connecting the Beebrain to your computer via USB and firing up Betaflight. Make sure you've downloaded, installed, and done a test connection to the FC before flashing. If this is your first time in the configurator, full instructions can be found on the Betaflight Wiki.
Once you're able to connect to your flight controller, plug it in via USB and click the Firmware Flasher tab.
Choose the BEEBRAIN target and then select the latest firmware version. Click Load Firmware [Online] to download the latest file. Once that downloads, click the Flash Firmware button and wait until the board finishes flashing.
Now that the Beebrain is up-to-date with the latest version, it's time to connect and configure your transmitter. We've made a video of the configuration on a Taranis. Because there are so many little steps, we've created a video which covers the basic setup and the flight timer configuration.
FrSky Taranis Binding Instructions:
DSMX (Spektrum) Binding Instructions:
FrSky Bonus - Setting a Flight Timer
For this build I use a flight timer on the Taranis to keep track of my battery usage. These steps show you how to set a timer that runs while your throttle is above zero. We also will set alarms that warn you as you reach the time limit.
Flying a battery for 2:30 leaves me with roughly 3.75v per cell. Finding the right flight time for the battery usage you want is a process. By starting with the timer a bit low, flying a battery, and measuring the remaining voltage, you can find a flight time that works for your setup within a few batteries.
The last step we need to do before our maiden flight is configuring the Beebrain via Betaflight. For those of you who've built an FPV racing quad before, these steps will be very familiar. Start by plugging in the Tiny Whoop and connecting to Betaflight. In the main configuration tab, adjust the following.
Starting in the Configuration tab, change the ESC/Motor protocol to Brushed. Enable Motor PWM Speed Separated from PID Speed. Set the PWM frequency at 4000. Ensure the rest of the settings look correct and the minimum throttle is set at 1030.
Continue scrolling down and set the Receiver Mode to PPM RX input. Turn off VBat.
In system configuration set the Gyro Update frequency and PID loop frequency to 1KHz. Turn off the Barometer and Magnetometer.
Lastly enable airmode.
Continuing on to the PID Tuning tab, set the PID's and Rates to the Beebrain suggested defaults:
In the Receiver tab, ensure the Channel map is set to TAER1234. At this point you can power on the Taranis and ensure the configuration is correct. As you move the inputs, you should see the values change. Be sure to confirm you set a switch to AUX 1 as we will use it as an arm switch.
Last, in the Modes tab set ARM to the switch you set to AUX 1.
Charge up some batteries and enjoy the maiden flight! Leave any questions or comments below.
Last updated on June 2, 2017