Print WARNING if PID control is called before updating sensor values

[nyxrobotics]

Abstract

If the PID loop is called multiple times with no sensor values updated, feedback control will not function. At the beginning of the PID control function, it is necessary to check if the sensor value has been updated or not. If not updated, WARNING should be displayed.

Purpose

Implementation Details

[nyxrobotics]

When a sensor value is updated, it enters the following function https://github.com/sbgisen/vesc/blob/d96dcc2d81419f33647b37b249769c0101b7b7f5/vesc_driver/src/vesc_interface.cpp#L80-L83

[nyxrobotics]

When running vesc alone, it responds fine even at 100Hz.

[nyxrobotics]

No error or warning is generated when control_rate is set to a value greater than the communication cycle available. (ex. 10000Hz)

[nyxrobotics]

The flow of communication between PC and vesc is

• Target values are sent from PC to vesc
• PC sends request to vesc
• Send sensor information from vesc to PC

It is the timing of the transmission that needs to be checked to see if the communication is working in time.