The Philips SmartPro Easy has up to 23 sensors that help it learn about the living space. This allows it to choose a structured path for cleaning. If the different rooms are not separated by high thresholds, it moves independently through the whole flat. If it runs out of battery, it notices this in time and returns to the charging station beforehand. It can also be programmed to go on regular rounds. Does this answer help you make a decision?

Can you tell me about the volume how much in DB approximately ?

My Irobot 980 cleans very well, only occasionally there is something "lying around", but that is the case with every robot and I have had others before. Otherwise, it always vacuums the whole area - I have three rooms - and all of them are clean afterwards. The Samsung, for example, was terrible, it wandered around completely without a system, the Roomba does it according to a system.