Need clarification on GPL license to distrbute software commercially

We want use the Ardupilot firmware without modifying in our project with custom GCS, for commercial purpose. So, is it mandatory to publish the source code of our project ?

Thanks

I am not a lawyer or one of the code maintainers.

As I read it, you can use Ardupilot for commercial purposes as long as you either include the Ardupilot source code with the product, or include a written offer to provide the source code (which could be handled by simply pointing them at the upstream Ardupilot git repo as long as it’s still up and running).

I would not expect you to need to publish the source code for your GCS.

From ardupilot/COPYING.txt at master · ArduPilot/ardupilot · GitHub

  1. Conveying Non-Source Forms.

You may convey a covered work in object code form under the terms
of sections 4 and 5, provided that you also convey the
machine-readable Corresponding Source under the terms of this License,
in one of these ways:

a) Convey the object code in, or embodied in, a physical product
(including a physical distribution medium), accompanied by the
Corresponding Source fixed on a durable physical medium
customarily used for software interchange.

b) Convey the object code in, or embodied in, a physical product
(including a physical distribution medium), accompanied by a
written offer, valid for at least three years and valid for as
long as you offer spare parts or customer support for that product
model, to give anyone who possesses the object code either (1) a
copy of the Corresponding Source for all the software in the
product that is covered by this License, on a durable physical
medium customarily used for software interchange, for a price no
more than your reasonable cost of physically performing this
conveying of source, or (2) access to copy the
Corresponding Source from a network server at no charge.