QuadProtoBoard
A custom flight controller for prototyping
innovative quadcopter designs.
(1 to 3 minute read)
The QuadProtoBoard follows my AFTR project and is my most advanced circuit design project as of yet, earning me second prize at the 2024 Sierrathon Design Competition. It is the culmination of hundreds of hours devoted to studying circuit design and layout over the last three years.
This writing will attempt to cover the broad points of this design, but for more information I suggest viewing the 20 page professional grade datasheet that I created to showcase the design.
Using state of the art circuit design software(Altium Designer) I created a 141 component 4 layer board using modern high speed design methodologies as well as an economic approach focused on manufacturing efficiency(the design meets most fabrication houses' non-advanced production requirements), all on a package that is 50x50mm, or a little bigger than a silver dollar.
The QuadProtoBoard is a versatile flight controller ideal for prototyping and developing innovative UAVs. Compatible with most 20x20mm and 30x30mm 4-in-1 ESC boards, the QuadProtoBoard features a 6-axis IMU, a magnetometer for directional navigation and position tracking, programming via JTAG and USB-C, RX/TX capability in the 2.4GHz band, external FPV module capability, a buzzer for locating crashed units, and three digital communication protocol outputs for interfacing with secondary prototyping boards. The power system accepts 2S through 6S LiPo batteries, with the battery voltage and 3.3V rails available at screw terminals for external peripherals.
The secondary boards could control weather sensors, additional guidance sensing, peripheral motors, additional drive motors, or anything else.
The power distribution system can supply 3.3A maximum of battery current to the prototyping ports, is compatible with 2S through 6S Li-Po batteries, and features a current consumption monitoring system to analyze power usage and monitor battery life.
Seen here is a multi-layer printout of some of the key design layers including top layer signals/power, silkscreen, and pads.
Modern design practices were followed carefully in this design, including:
An EMI conscious stack-up of Signal/Pwr - GND - GND - Signal/Pwr.
Stitching vias at every signal layer change to provide clean return paths.
Parallel tracing along battery voltage trace to allow for high current flow.
Particular care was taken in the RF section of the board(bottom center):
Uniform balun circuit layout to minimize phase distortion.
Fencing vias to isolate and protect the sensitive RF signals.
Ground plane keepout under antenna to minimize impedance mismatch.
Antenna spaced away from switching ICs and board edge to minimize interference issues.
The rest of the layers are available for view in the board's datasheet.
Schematic.pdfThe schematics were designed to be clean, concise and informative.
Calculation notes can be seen in various spots and are intended to aid a quality control team to easily verify the effects of various circuitry.
I enjoyed making this project and look forward to making my next board. Please contact me at clayclemmer@gmail.com to get in touch with me, or view my resume here.
The datasheet for this board is available at this link, or viewable below.
F001 Datasheet.pdf