In the first installment of this series, I assembled most of the frame components of the Strider Mini Quad. I also installed and soldered the motors and ESCs. Although the flight controller was installed in the frame, it still required attachment of the various wires and configuration of the firmware within. Let’s focus on those tasks and keep moving.
Plugging in the CC3D
The flight controller is the nerve center of any multi-rotor. It takes your control inputs and the data from its onboard sensors and translates it all into commands for each of the ESCs. There are several different brands of flight controllers. Considering all that they do, most of these units are incredibly small. The flight controller I chose is the OpenPilot CC3D (CopterControl 3D), which fits perfectly on the Strider’s stock flight controller mount.
From a wiring standpoint, the flight controller is situated between the radio receiver and the quad’s ESCs. First I attached the ESCs to the CC3D. The CC3D has a bank of pins that accept the standard receiver plugs found on most consumer RC equipment. The quad’s motors are numbered sequentially as you go clockwise, with the #1 motor being the front left. I attached the plug from this motor’s ESC to the #1 pins on the CC3D and then followed suit with the other ESCs.
To connect the CC3D to my Futaba R617FS receiver, I used the 8-wire harness included with the flight controller. The colors of my wires didn’t match those on the OpenPilot diagram, so I just referenced the pin order. The first two pins are negative and positive power. The remaining pins are signals for channels 1-6 respectively.
PPM (Pulse Position Modulation) receivers like the FrSky model shown in the Strider manual, and Sbus receivers like some Futaba models require only one signal wire for all of the channels. The R617FS is a standard PWM (Pulse Width Modulation) receiver. As such, it has three pins for each channel: positive, negative and signal. The positive and negative connections from the CC3D can be connected to any channel on the receiver. The signal wires must be connected to their assigned channels.
In addition to the connections to the CC3D, I made a signal wire connection from the receiver to a pin on the Strider’s frame. This wire allows a 3-position switch on the transmitter to operate the Strider’s built-in LED lights, lost model alarm, and also toggle crosshairs in the OSD function. I used channel 7 for this, since it was already mapped to a 3-position switch on my Futaba 7C transmitter. By going this route, I did not need the channel 6 signal wire from the CC3D.