I am currently in the engine selection phase. Taking into account that the robot will weigh about 15 Kg. And that the movement of the same must be slow and precise if it can be a selection it could be something similar to these:
https://www.hackster.io/hackerhouse/make-an-autonomous-follow-me-cooler-7ca8bc
What do you think?
Propulsion
The following tool might help you get an idea of the torque and RPM you need for your robot:
https://www.robotshop.com/blog/en/drive-motor-sizing-tool-9698
The link to the motors for the cooler robot gives 12V, 120rpm, 1.5Kg-cm geared motors. It’s hard to tell if they are planetary or spur gears. RobotShop offers a similar looking motor here: https://www.robotshop.com/en/6v-97rpm-metal-gearmotor.html
Note that we can special order a motor which is almost identical to what you linked to, but 130rpm instead of 120.
If you need something “preceise” however, you might consider a gear motor with a rear encoder:
https://www.robotshop.com/en/gear-motors-with-back-shaft.html