Hi, I have my own simulation software which I am passing HITL data to a PX4 operating in SITL mode. According to this website Simulation · PX4 Developer Guide I am passing the required HITL_* message to the PX4 via UDP/MAVLink.
For configuration I am using an Octocopter-X mixer and Ive set SYS_AUTOSTART to 8001 in the parameters file. This is read by the SITL PX4.
I receive back actuator controls over UDP in my own simulator and therefore the actuator controls. I have two questions:
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Do the actuator outputs match the airframe reference for 8001 here if I’m using ROMFS/px4fmu_common/mixers/octo_x.main.mix and setting SYS_AUTOSTART to 8001?
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Can someone explain to me in depth the -1 to 1 range for actuator outputs? I realize somewhere in the PX4 software that it is converted to PWM, but I need to do the same thing in my engine model, or at least map it to RPMs. Is -1 spinning the rotor in reverse, 0 neutral, 1 spinning rotor in normal direction? The MAVLink definition is not very helpful (http://mavlink.org/messages/common#HIL_ACTUATOR_CONTROLS)
Appreciate any clarification.