mBot Ranger | Quick swap battery holder case + fall out protection

mBot's are nice and affordable gadgets for kids to learn programming logics with Pyhton. 

The Ranger model has only one problem: The battery pack wich is only accessable by unscrewing the top, relies on AA batteries, so you have to replace this quiet often. Besides that if the mBot drives against a backpack or someting, it rolls over and the batteries fall out, so you have to unscrew again…

I designed a case that you screw in once and then open it at the back. The battery pack can be slieded out, batteries can be replaced, all easy and gently to the bot. The screws at the back can be removed with the included screwdriver. The case is attached with the original screws from the old battery holder.

Printing:

• PLA (i used PETG, but it is stringy)
• no supports
• Infill Cubic 20% 
• 0.3mm Draft or 0.2mm Speed

Parts:

• Threaded Inserts M3x5,7 
• 2 M3x8 screws - DIN 912