Small UAV vs Large UAV autopilots

I may think this is a little stupid question buzzing on my head but I really need your guys help. This is my first post on the forum after I had signed up for DIY drones. I have been reading most of the forums on this site and I was truly impressed how specialize and helpful you guys were.

I have conducted a research on various autopilots and I realize some of them have a specification so called a "weight limit". For instance a UNAV 3500 allow a designed for fixed-wing airframes with a gross weight of 5~55 lbs. But what if the system is applied on a bigger and heavier airframe? Does it matter if an autopilot used for micro UAVs be implemented on large UAV? How does it affect the operation of the plane?


Thx, sorry for my poor English!   

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  • Technically there is no limitation, except for the power/torque of the servos used..  An APM2.5 could be used to guide a 747 if you so desired.

    The real issue is the level of redundancy, fail-safe and fault management on each system and what the requirements are in this area of the class of UAS you are trying to develop.  Electromagnetic compatibility and interference (EMC/EMI) is also another huge area that is not sufficiently addressed to make it wise for APM's to fly Jumbos

    And another thing... on "high-level" UAS's the autopilot / flight controller is usually talking bi-directionally to the servos over a serial link of some form.  RS485 is used on one system I am familiar with.

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Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25