To tame these millipedes, put some bug repellant on you and a soothing balm and spoiled meat in your hot bar. There are found in caves.Then, approach it from the back and feed it your food. Once tamed, if it is on turret mode, it cannot move. So disable that so it can.

Now that you have yourself an arthro, you can collect all the artifacts with ease!! (Nothing will attacked it unless provoked)