ESC
ESC (electric speed controllers) are required for driving the brushless dc motor.
While most esc's will work well with fixedwing, rotorcraft have higher requirements.
Positive features for rotorcraft:
- faster response to input signal !!!
- higher torque
- accept higher or other input signal (higher pwm input or I2C)
- less noise
Standard ESC can be used, but with a little work and SimonK's firmware e.g. they will work better.
AVR (ATmega) based ESC
Simon Kirby develops an alternative firmware for ATmega based brushless motor controller, written in assembly.
This software will use the maximum capabilities of the hardware.
- 16MHz operation on most boards
- 16-bit output PWM with full clock rate resolution (~18kHz PWM with a POWER_RANGE of 800 steps)
- 24-bit timing and PWM pulse tracking at full clock rate resolution
- ICP-based pulse time recording (on supported hardware) for zero PWM input control jitter
- Immediate PWM input to PWM output for best possible multicopter response (but NOT where soft start or really any significant current limiting is needed!)
- Accepts any PWM update rate (minimum ~5microseconds PWM low time)
- Optimized interrupt code (very low minimum PWM and reduced full throttle bump)
- Configurable board pin assignments by include file
- Smooth starting in most cases
- Forward and reverse commutation supported, including RC-car style reverse-neutral-forward PWM ranges, with optional braking
Hardware compatibility (Openpilot)
Hardware compatibility (google docs)
sim-/tgy git repository.
SiLabs based ESC
Some newer ESC are build with a Silicon Labs MCU with a 8051 core.
They have a C2 programming interface.
Steffen Skaug provides an alternative firmware, written in assembly.
Programmer:
owsilprog uses a Arduino.
Silicon Labs Toolstick available at Mouser for 8€.
Since the Toolstick can not be connected to wires directly, little modification is required.
bitdump/BLHeli git repository
Open BLDC
Open hardware / open software brushless controller project.
From small low cost up to 200A continous hardware, but currenty unter development.