import bpy, json, math
from mathutils import Vector
rig = next(o for o in bpy.data.objects if o.name.startswith("DockArm_Rig"))
out = {}
for k in (1, 2, 3):
    t = bpy.data.objects["_Tender%d" % k]
    pb = rig.pose.bones["Arm%d_Head" % k]
    wrist = rig.matrix_world @ pb.head
    tl = t.matrix_world.translation
    inv = t.matrix_world.inverted()
    out[k] = {"tender_origin": [round(c, 4) for c in tl], "wrist": [round(c, 4) for c in wrist],
              "wrist_in_tender_frame": [round(c, 4) for c in inv @ wrist], "parent": t.parent.name if t.parent else None,
              "parent_bone": t.parent_bone, "inst_offset": [round(c, 4) for c in t.instance_collection.instance_offset]}
# the Kazah's collar in the ship: centre of its Hatch_Collar ring in the Tender's frame
kz = bpy.data.objects["_Tender1"].instance_collection
hc = next(o for o in kz.objects if o.name.startswith("Hatch_Collar"))
vs = [hc.matrix_world @ v.co for v in hc.data.vertices if abs((hc.matrix_world @ v.co).z - 0.75) < 0.03]
cx = sum(v.x for v in vs) / len(vs); cy = sum(v.y for v in vs) / len(vs)
out["kazah_collar_centre_own_frame"] = [round(cx, 4), round(cy, 4)]
print("PROBE", json.dumps(out))