Schematic
Deepslate Tunnel Bore
Comments
This can be made fully automatic by using a regular minecart, replacing the rail with powered rail, adding a deployer with redstone torches to the side of the other deployers, and adding another harvester at the back (attached to another linear chassis). Also, the AFK seat is too high, and your character will take damage there. You can put the seat on the new chassis you added if you followed the steps above, and you should be fine.
