You probably should just create a couple astromining ships for the purpose.
Get two copies of the Astrominer, mark one as full, and one as empty (in dev notes). Attribute Flags should be as follows:
Empty: CanTurn, HasDirectionGoal, DoesBounce, CanEngage, CanBeHit, AppearsOnRadar
Full: CanTurn, HasDirectionGoal, AppearsOnRadar
...and Engage Flags as follows:
Empty: CanOnlyEngage, default engage key, Level Keys A, C (should be unique)
Full: CanOnlyEngage, Engage Key A, B, C, D
On the Full version, give it a small Arrive distance, and as its Arrive Action, use Alter Resources and Alter Basetype to Empty Astrominer Reflexive.
Copy the default asteroid set, and on the smallest, give it a collide action to Alter Basetype to Full Astrominer inclusive of build flags A-C-.
In the map, add 3-5 astrominers near the astromining station, with StaticDestination and their initial destination set to the astromining station.
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(~%) ssh localhost
The authenticity of host 'localhost (127.0.0.1)' can't be established.
RSA key fingerprint is 93:33:b4:fc:b8:03:b4:45:15:31:99:1a:a3:1f:a5:ac.
Are you sure you want to continue connecting (yes/no)?