Bachelor Thesis: Development of a Serial Electronic Speed Controller (ESC) for Brushless Motors
The Networked Autonomous Aerial Vehicles (NAV) group of the Karl-Popper-Kolleg (KPK) is focusing on a realistic application scenario in autonomous 3D reconstruction with small-scale collaborative aerial vehicles. For advanced control and state estimation, telemetry information (current, voltage, current RPM, set RPM) of each motor need to be accessible at a high rate.
The current consumer off-the-self top notch ESC communicate via the DSHOT protocol, using multiple (16) PWM pulses (a bit) to describe a digital frame. On a MCU, this would mean to write 16 PWM values representing 0 or 1 into a register. On the receiver side it is even more complicated to interpret these bits correctly. On MCU one is used to write a single byte into a HW register for a dedicated module, such as SPI, UART, CAN, I2C, to get it send over a interface and usually when a byte is received a interrupt is created. Not with DSHOT, as there is no dedicated HW module integrated in MCUs, as it is not a common standard and hardly used, just for ESCs. Therefore it is software emulated and causes tremendous CPU load. If we want high refresh cycle rates and to use the MCU for other tasks then emulating the ESC commands, a different standardized interface needs to be used.
The Student Researcher will first investigate on related work to get expertise in the field of Electronic Speed Controllers, Flight Controllers (FCU), different serial interfaces and bus types. Then, based on the students decision, a reference design needs to be implemented, including the hardware and firmware design.
Infineon’s reference design is rated up to 30A and uses a UART communication interface and should be used as template. Finally the designed ESC needs to be tested on a PX4 based FCU.
Milestones and Extensions
M1: Selection of Interface
M2: Protocol Specification
M3: Protocol implementation in FCU firmware and testing
E1: Evaluation of the Performance
- Good knowledge in Electronics, Signal Integrity, MCU programming, and GIT
- Self-driven motivation to learn new topics
Period and Contacts