How accurate is the ROS2 timer on RasbperryPi ? - Speaker Deck

How accurate is the ROS2 timer on RasbperryPi ?

by maehara-keisuke

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How accurate is the ROS2 timer on RaspberryPi ? 2021.05.05 ROS Japan UG #42 LT@Zoom 前原　圭祐 (MAEHARA Keisuke)

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2/4 © 2021 MAEHARA Keisuke Overview ● My Interest – To use `ROS2 Framework` in `Control System` ● Objective – To understand ROS2 timer accuracy limitation ● Progress from my past presentation ( in ROS Japan UG #34 LT ) – `Dashing`-> `Foxy` – `amd64` -> `RaspberryPi 4B (arm64)` – Disable console log message

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3/4 © 2021 MAEHARA Keisuke System Configuration kernel layer libgpiod ROS2 layer Single Threaded Executor CtrlLaw IoHandler Component1 Component2 plant input plant output note : two nodes in single process, but not using Zero Copy note : `plant input` is electrically connected to `plant output` source : https://www.st.com/ja/evaluation -tools/nucleo-f446re.html

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4/4 © 2021 MAEHARA Keisuke Result(histogram of control period) ● ROS2 timer(= control period) is set to wake up every 1[ms] ● Standard Deviation is about 10[μs]