LG Roboking

I recently bought an LG Roboking robotic vacuum cleaner and thought I’d write up a review of it, and perhaps clear up some misconceptions I’ve seen online.

The version I got is the LG Roboking VR6171LVM, which is the second newest Korean model at the moment. The Roboking is sold under the name LG Hom-bot in a few European countries, but not here in Sweden.

I will be comparing it to my old iRobot Roomba Discovery SE (4xx-series). I’ve been using the Roboking daily for about two and a half weeks.

Prepare for a loooong read :) .

Noise level

The first thing that struck me when I started up the Roboking was how silent it was. That was the main selling point for me, since I had become weary of the noise the Roomba makes. The newer Roomba models are more silent than the one I have. I’ve only heard one in a store, but I think it’s significantly louder than the Roboking. The specs say the noise level for the VR6171 is 48dB(A). The noise mainly comes from the engine driving the wheels and the vacuum engine.

You can easily watch TV while the robot is cleaning in the same room. You might have to turn up the volume a bit. To give you an idea of the sound level I could no longer hear the enemies’ foot steps while playing Call of Duty on the PS3 unless I turned up the volume. The most noise comes from it clonking against the floor when going over doorsills or trying to get over things it thinks are doorsills, so you might not want to run it at night out of consideration for your neighbours.

The main brush makes more noise if you run it on tile or “against the ridges” on a structured carpet.

iRobot Roomba and LG Roboking

Getting over doorsills and carpets

I had read that the robot could get over doorsills and carpets up to 10mm high. I was a bit worried that it wouldn’t be able to enter my bedroom since the threshold has a height of 13mm. It turns out it can get over it, but not in all cases. If the Roboking tries to enter the room at a 90 degree angle against the threshold, it won’t go over it, but if it comes in at an angle it works. As it turns out, it always comes at an angle with the current layout of my apartment.

Getting over thresholds

The robot also manages to get on top of both the carpet I have in the living room (~5 mm thick) and the thin carpets I have inside the front door. When I was using the Roomba I had to fold away the thin carpets or it would “choke” on them.

Roboking on carpet

When I was reading about the Roboking online I heard people say that it was “carpet shy” and “there’s no pattern to when it can get on top of a carpet or not”. This is how it works: when the robot comes upon the edge of a carpet (or any other elevated area) it will avoid that edge, but take note of it and save it for later. It will clean the surrounding areas and then return to the carpet and clean it. The same goes for doorsills, at least if you use the “cell by cell” cleaning program, which means it will clean one room at a time.

Climbing a chair

During the daily cleaning of my apartment it will sometimes clean the living room (except the carpet), the room inside the front door, the carpets inside the front door, the kitchen, the bedroom and lastly the living room carpet. Other days it’ll clean the whole living room, then the hallway, bedroom and last the kitchen, depending on the conditions that day.

It, like the Roomba, tries to climb my living room chair (see the picture). It won’t get stuck though. I’ve only had to free the Roboking once. More on that later.

Navigation and base station

The Roboking uses SLAM navigation using top and bottom camera (the bottom one is like an optical mouse) and ultrasonic sensors. It doesn’t bounce around like the Roomba. This means it can clean the whole apartment evenly in one run. The Roomba might clean one room very thoroughly while leaving another room virtually untouched. Some Roomba models have IR lighthouses that make it clean one room at a time. I used virtual walls with my Roomba to basically clean half the apartment at a time.

This version of the Roboking also has a memory feature which means that if the battery runs low, it will return to the base station and recharge and then return to where it left off. It also does this if you manually stop it and return it within one meter of where you picked it up. The only time I’ve used the resume feature is when I’ve cleaned the apartment twice without recharging. The battery lasts almost two full cleaning cycles (53 m2 minus the bathroom).

Base station

The LG base station is better than the iRobot one. It’s a single unit with the power supply built in, which makes it more stable and it won’t slide when the robot backs out like it can on the iRobot one. A neat feature is also that if you place the Roboking within 10 cm of the base station it will align itself and dock automatically.

I haven’t had any issues with the Roboking not finding its way back to the docking station when I’ve started the cleaning from docked position. I don’t even have the base station positioned according to the description in the manual, which requires 1 meter on either side. When you start the cleaning program in the middle of the room the robot will follow the walls until it finds the docking station, if it hasn’t already found it.

While the Roomba leaves a big area near the base station untouched, the Roboking cleans very close to the base station.

It should also be added that, while the power supply is listed as 220V 60Hz in the specs, it seems to be multi-voltage as it works fine in a Swedish electrical socket, which is 230V 50 Hz.

Getting around objects

The Roboking doesn’t have a bumper like the Roomba, but relies on ultrasonic sensors. I think there are IR sensors behind the front panel and that there is some kind of accelerometer or gyro built in.

Low clearance

Let’s start with the good. The Roboking cleans very close to the walls. It also circles around furniture legs. It can even detect the 1 cm round metal legs on my kitchen chairs. It almost never gets stuck. It also has the same low (9 cm) clearance as the Roomba.

Now the bad. There seem to be some blind spots in the Roboking’s sensors. Sometimes it will bump into objects. This is no big deal. It realises that it has bumped into something due to the accelerometer I guess. What’s worse is when it starts pushing or grinding against objects. This mostly happens with the radiator in my living room. It doesn’t see it.

It seems that the most common situation when it starts pushing is when it detects an object and tries to go around it. It’s like it’s miscalculating its own width or the width of the obstacle because it starts grinding against the object it just detected. During the first run in my apartment it started pushing around a pedestal with a flower pot on top of it. I was like “F**K!”. This just doesn’t happen with a robot that has a bumper sensor.

Pushing against things

It also kind of wedges itself under my bookshelves (standard IKEA bookshelves) and starts to grind away, which scratches up the top of the robot. It won’t get stuck though. It’s actually a bit surprising that it does this, because one of the changes LG made to this generation of robots was to tilt the sensors upwards to avoid having the Roboking wedge itself under furniture.

Wedges and scratches itself up

Actually, the Roboking got stuck once. Like I said, it can detect the thin legs of my chairs, but as soon as a leg ends up in a blind spot it will start pushing the chair around.
I have one of those chairs in my bedroom and once it managed to push it out in such a way that the Roboking got stuck between the leg of the chair and the radiator. It’s a pretty unlikely scenario. If anything good comes with all the pushing, it’s that if the Roboking can’t find its way out from behind a chair, it will push the chair out of the way :lol: .

This pushing against objects is the single biggest issue with this product. It’s not that big a deal for me, in this apartment. But it might be a big problem for others.


The Roboking only has one main brush as opposed to the two counter-rotating brushes on the Roomba. Over all I get the feeling that the Roomba digs deeper with its brushes, but that the Roboking has a more powerful vacuum engine.

The Roboking is very good at picking up dust and hair. I don’t have long hair, so I can’t tell you if it gets tangled up like on the Roomba. It seems like the Roboking isn’t as good at picking up larger pieces of dirt like sunflower seeds, but I haven’t really done a side-by-side comparison. It could simply be because the Roomba goes over the same area so many times.

The navigation of the Roboking is described as going over the same area only once, but in reality it goes over some areas more than once. This is mostly around obstacles, where it has to alter its course to find a way around. It also, naturally, goes slower around obstacles. This means that it will clean more thoroughly in tight areas than on open floor surface, which is where the dirt gathers anyway. In that sense it’s similar to the Roomba.

I’ve noticed that while it might have missed one seed close to the carpet edge one day, it picks it up the next day. I tried the spot cleaning mode once with some pieces of dry instant noodles on the floor (I had broken a block of ramen into two and some small pieces fell on the floor). It seemed like the Roboking was just pushing around the larger pieces, so don’t leave sharp objects on the floor. Things that aren’t as hard, like cheeto pieces will get crunched up and sucked into the dirt bin.

Another day I was throwing away a dried up basil plant and a lot of dry leaves fell on the floor. I picked up the bigger leaves and left the rest for the daily cleaning. I was surprised to see that all of it had been cleaned up during the daily cleaning cycle. It was nearby a chair though, which might have contributed to the robot going over the area more times.

An issue with the iRobot Roomba is that it will leave dust bunnies when it transitions from floor to carpet. I have not noticed this problem with the Roboking, which has a flap that covers the opening to the dust bin. This flap prevents dirt from spilling out once it has been swept and sucked into the bin. The flap causes a clacking sound when it closes, so don’t be alarmed when you hear this when the Roboking is running. It’s perfectly normal.



This robot is very low maintenance (so far, I might add). Most parts are enclosed, so dirt can’t get in. This is miles away (ahead) of the Roomba, where dirt gets everywhere.

The Roboking has its dirt bin in the centre of its body. The vacuum engine sucks air trough the same opening as the main brush is sweeping dirt into and it all ends up in the same bin.

Emptying the dirt bin is a breeze. You lift the bin out of the robot, open the lid and empty it in the trash. When you take out the bin, everything is closed, so no dirt will spill on the floor when you do this. The bin consists of a plastic container and a set of filters: a mesh attached to the bin, a foam filter and a HEPA filter. The filters keeps dust out of the robot and also keeps it from being blown back out into your home.

When I empty the bin, I use the brush that comes with the robot to remove dust from the mesh filter. You can’t just shake it over your trash can. I also use it to brush out small particles from the HEPA filter about once a week.

Dirt bin

One big plus with this dirt bin is that you can rinse it off with water. There are no electronic parts in the bin. The filters are also washable.

The main brush is also easy to clean. It doesn’t seem to get nearly as dirty as the brushes on the Roomba.

Ease of use

The Roboking is very easy to use. All text on mine is in Korean, but it’s pretty intuitive. There are also stickers here and there with instructional pictures on them. It also speaks to you, letting you know what you need to do (“check the dust bin”) or what it’s doing (“charging started”). This is all in Korean though, so it’d be easier if it spoke your language.

There are four touch buttons on the back of the Roboking (timer, on/off, cleaning mode and charging/return to base). These controls, as well as directional controls, are also available on the remote control.

You can schedule the next cleaning by using a timer which lets you delay the start by 1 to 12 hours. You can’t set it to clean every day automatically. It’s only possible to schedule one cleaning cycle at a time, but the more I think about it, the more I prefer the timer over a proper scheduler.

The timer is great if you, for example, leave for work very early and don’t want to disturb your neighbours, who might be sleeping. You can then simply set it to run a few hours later when most people are up or at work.

Microfibre mop

There’s also an optional (dry) microfibre mop attachment. You just click it in place without having to turn the robot over. The manual states that the Roboking won’t climb carpets or doorsills when the mop is attached, to avoid leaving dirt on the carpet. But it does go on my living room carpet even with the mop attached. It avoids the bigger thresholds and the thin carpets inside the front door, though. It does go on the front door carpet in one case: if it exits the kitchen (the threshold is very low on the kitchen side) and goes straight onto the carpet. The mop catches additional small particles, but I don’t feel that it makes that much of a difference. Since it also goes on carpets anyway, I rarely use the mop attachment.

Microfibre mop


You can tell that there’s some serious AI going on in this robot, since it will sometimes stop to “think”. At least, that’s what I think is going on. When I’ve subjected the robot to very tricky situations it will try a few strategies to get out, then it will stop for a little while and decide on an alternative strategy. This will also happen at times when it’s calculating how much is left to clean. You’ll notice this behaviour just before it decides that the cleaning cycle is complete.

Sometimes it will spin 360 degrees to get the lay of the land.

One odd behaviour is that it seems to have restarted/rebooted itself on two occasions. I don’t know what causes this. It could be a safeguard for software bugs. Either way, it restarts itself and continues cleaning.


I’ve already described how the Roboking can clean my apartment nearly twice on a single charge, but I thought I’d add that the Roboking uses a new type of Lithium Polymer battery which is supposed to last 3-4 years before going bad, while the battery the Roomba uses lasts one year.

A nice feature is the main power switch at the bottom of the Roboking. That means that you never have to remove the battery until it needs to be replaced.


I’m very pleased with the cleaning performance of the Roboking. It’s good with dust and hair, which is what I want it to clean up on a regular basis. It cleans the whole apartment and does it silently. It’s also hygienic with it’s HEPA filter and easy-to clean dirt bin.

This robot would have been near-perfect if it weren’t for the issue with it pushing and grinding against objects. It’s a major issue.

Pros: silent, good navigation (cleans whole apartment), user friendly, easy to clean, HEPA filter, good battery, good vacuum performance, timer, good build quality

Cons: has blind-spots, pushes and grinds against furniture, misses some dirt, not sold in Sweden (no domestic service)