CAN Sensor Interface Brainstorming
- Michael Botros
- Daniel Puratich
Project Owners: @Michael Botros
Action Items:
Update needs assessment and implementation strategy
Meet with EFS
Project Timeline
As of writing, this project is not comp critical
Based on initial difficulty assessment and scale of project, this project could target testing and implementation in the next competition cycle (2025)
Basic Timeline
Research and Full Architecture Outline - October/November 2023
Component Selection - December 2024
Schematic - January/February 2024
Layout/Routing - March/April 2024
Bring-up and validation - May 2024
Needs Assessment
Main goal of this project is to be able to route long sensor/data cables across the drone and maintain signal integrity. A differential signaling method is desired that is also easy to implement to minimize common mode noise and allow long data wires to be routed to various sensors on the drone.
This solution needs to be flexible and adaptable for various airframes and protocols.
This board will serve as communication interface board that will allow half duplex communication between I2C, SPI, UART and CAN
Board should be as small as possible and be mounted on a 30x30mm pattern
Board should support a differential protocol, 5V input and support I2C, SPI and UART output
Should there be separate small boards for I2C, SPI and UART independently or one large board with all connectors?
Connectors following: Pixhawk Electrical Connector Standards
LEDs for status
Implementation Strategies
Method 1:
I2C SPI to UART bridge
Use CAN transceiver to get serial data from CAN bus and feed that into the bridge
Method 2:
Use CAN transceiver to generate serial data and feed into MCU to buffer. Use MCU with EFS drivers to transmit CAN data on I2C or SPI or even UART
Perhaps some STM ICs support CAN directly
More compact solution, one IC can breakout for all communication standards
Method 3:
Power over Coax
Use coax cable to transmit power and data serially on the same line
Requires complicated filtering and drivers but only requires one coax cable per sensor