The Deebots have brushes on both sides of them, not just one and they sweep right into the skirting boards. Round machine do miss the very depth of a corner though, but only by a couple of cms. Also, most single brush machines have a brush on one side, not in the middle so they do get the skitrting boards
I'm talking about the main brush, not the side brush. The main brush on most round machines are between the wheels and the side brush isn't going to do anything for getting deep into the carpet near the skirting boards. The side brush is only useful for hard floor or perhaps agitation of carpet surfaces only.
Brush type and placement has the biggest impact on deep carpet cleaning, this has been confirmed by Vacuum Wars YT channel, the Roombas still come out on top for carpet cleaning because of the dual brush design even though their suction rates are usually lower than other brands.
The problem with these robots that have the large stations to empty the bin is that you can see them. I have my Xiaomi under a cabinet, it is therefore invisible until it comes out to clean and it only needs emptying once per week which is easy to handle.
My D7 lives under the TV media unit and it's nice that it's out of sight. I'm not too fussed about auto empty, but would put up with a large station if someone made a bot that was D shaped, with LIDAR, VSLAM and it's charging dock happened to be a large self emptying unit.
The D7 is such an annoying device because it ticks most of those boxes but I find the navigation algorithms to be poor vs say Xiaomi. What I'm finding is:
- The bot will often get into a tight spot, then will back out of it whilst attempting a pointless turn which will result in the back of the bot climbing up the skirting. All it needed to do was reverse straight, turn on thr spot and edge forward during the turn if it detects possibility of the rear hitting the skirting board.
- The D shape could be used more to an advantage. It'll often be following a wall and when it comes across a recess, it'll gradually decrease distance to the new boundry - leaving a triangle of space not touched. What it should do is hang a hard right to get the D shape right into the corner and then back out.
I know these machines require an element of sacrifice such as not getting the perfect coverage for an easier life, but I find especially on carpet, you will need a proper vacuum cleaner to do the edges and corners.
Perhaps it's a moot point as you're likely to keep a proper vacuum cleaner for stairs, car and/or vacuum storage bags but this is such an easy fix.