Having had my fill of quadcopters after my last crash, I decided to build a tricopter using my three remaining motors (one was damaged in the crash). David Windestål of FliteTest has a simple and sturdy design (see his build video) that I followed to build mine. As such, I will only be posting information that is unique to my build.
The tricopter has been by far the most exciting multirotor I’ve built. Because of its ability to use thrust vectoring in the yaw axis (unlike other multirotors which rely on torque vectoring) the yaw authority is extremely high, allowing for quick and precise rotation. Also, following David Windestål’s method of using zip-ties to attach everything has saved me multiple times in crashes, allowing the components to break off without being seriously damaged. Once you go tri, you never go back!
The unique aspect of my tricopter is the light and siren system. I wanted something that I could fly at night and looked like a police vehicle. So I added red, white and blue LED strips, as well as a 102dB siren, and built a custom, Arduino controlled, driver circuit to power everything.
Parts for the tricopter (that differ from David Windestål’s design):
1 x OpenPilot CC3D (Flight Controller)
1 x Turnigy 380MAX Micro Servo (Metal Gear) (This servo has given me some trouble, but is acceptable given its low price. Make sure you buy extras)
4 x Graupner E-Props 9×5 (R and L) (These props have proven themselves on previous builds and are fantastic on the tricopter. No other props I’ve tried have been close to as good as Graupners)
Besides the above parts, all other components are either the same as used by David Windestål, or were recycled from my last quadcopter build (i.e. ESCs, receiver, etc.)
Parts for light and siren system:
1 x ProtoBoard (these are common and can be found at your local electronics store (RadioShack, ect.).
1 x Red LED strip (1 meter) (12v)
1 x White LED strip (1 meter) (12v)
1 x Blue LED strip (1 meter) (12v)
1 x 102dB Siren
1 x 12v linear regulator (again, these are common and can be found at any electronics store). Because I’m running a 4S battery (16.8v) I have to step the voltage down to 12v for the lights. This is unnecessary if you’re running a 3S battery (12.6v)
4 x MOSETs (can be found at most electronics stores). MOSFETs are solid state switches (like relays, but much smaller and lighter)
1 x Arduino Nano (The Nano is connect to spare channels on the receiver and controls the lights and siren via the MOSFETs)
1 x Various other hardware (male and female headers, wires, etc.)