4WD robot rebuild

Few months ago my path crossed with this 4WD robot from Keyestudio ( there are literally tons of clones available on internet)
I am not satisfied with look of this funny thing an there is also some features missing so I decided to give him a little ( rather big) rebuild. So this is work in progress.

TLDR:
1. Rear bumper / cover - done.
2. Holder for 10000mAh powerbank - done.

Next step : Front bumper with integrated ultrasonic sensors. - in progress

Last step: power motors directly with step-up converter/booster for better performance.
Last last :-) step: wireless charging with auto-homing.

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Step 1 rear bumper: there is no need for explanation - pretty simple design and printing.

Step 2 powerbank bracket: it is not some beautiful piece but for prototyping sufficient. For simplicity reason and convenient charging I decided to use some common noname powerbank that is used to charging 5V appliances. There w