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How Do Robot Lawn Mowers Work? Benefits, Drawbacks & FAQ

robotic lawn mower on the grass

Because mowing can be tiresome, homeowners craving a clean-cut lawn that looks fresh all season have to invest in alternative mowing options. In the past, hiring a professional to do it for you was the only available option or, at best, getting a riding mower. But times have changed, and how you can look after your lawn has also changed.

The latest lawn maintenance technology is robotic mowers that can cut your grass without any human input. These modern mowing machines work independently after the initial setup. Their tiny blades mow at scheduled times and the specified area of your lawn for the most convenient maintenance.

This piece will look at how this labor and time-saving technology actually works and dissect its mechanical and computer system setup. So keep reading to learn more.

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How Does it Move Around the Lawn?

A robot lawn mower navigates your lawn by random movement inside a boundary wire. The first thing you do is set up a low voltage boundary wire around your yard. The wire is a barrier, ensuring the robot does not go beyond a specific area. It also acts as a guide to the charging station. Whenever the robot is low on power, it will follow the boundary wire to where it can connect to a recharge center.

The boundary wire can be buried a few inches into the soil or placed on the ground if it has high insulation. Furthermore, robotic mowers have preinstalled programs to help them avoid obstacles on the lawn, such as big trees, flowers, or even children’s toys. This makes them safe not only for people around them but themselves as they cant mow anything other than grass. As an added safety feature, they will stop in their tracks and shut down the blades when they encounter something. Then the system will scan for an alternate route and change direction before turning the blades back on.

However, it would help if you placed the perimeter wire around large obstacles on your lawn to avoid your robot constantly running into them. Then, the boundary cable will always communicate to the robot to change direction, and the mowing will not be interrupted. On the other hand, some more advanced robot mowers don’t require a wire as they use GPS mapping to navigate your lawn.

In addition, their small size enables them to mow steep lawns without slipping or falling over. However, each model has the maximum gradient it can operate before malfunctioning.

Robotic lawn mower
Image By: MonikaP, Pixabay

What Cutting System Does a Robot Lawn Mower Use?

Compared to a traditional lawn mower, a robot will use a more power-efficient system to trim a lawn. A manual lawn mower will consume more power of its sheer size, blade designs, and urgency to get the job done fast.

However, a robot is designed to cut a small volume of grass per mowing session using tiny blades. This ensures the mower moves slowly and leaves little grass clipping that does not require picking—making them energy effective as well as providing your lawn with natural fertilizers.

The software that runs a robot lawn mower ensures the mowing session is random and that every inch of the lawn is attended. Frequent cuts ensure that you don’t have dense grass cuttings, and your yard will always look freshly cut.

However, manufacturer of robot mowers will fit either of these two cutting blades:
  • A solid mini blade: You will find your mower has one or multiple. These types of blades draw more power from the battery. Unfortunately, they also result in the mower being uncharacteristically loud. However, they are more effective mowers.
  • A rotating disk: These are the most common type of blades.
man fixing blade of robotic lawn mower
Image Credit: Anze Furlan, Shutterstock

The Charging System

Unlike a classic electric lawn mower that must connect to a power supply as it mows, a robot has a rechargeable battery. It also has a computer system to control mowing hours and charging cycles.

When the charge reaches a certain percentage, it will automatically navigate to a charging station by following the boundary wire to its terminal. Once fully charged, it resumes mowing while keeping to the set schedule.

Security Features

Installing a robot lawn mower is quite expensive. As it is a considerable investment, people are naturally worried about the security of such a device.

Manufacturers install antitheft control features such as:
  • Trackers for tracing exactly where your lawn mower is at any instant.
  • An alarm goes off any time they leave the perimeter wire.
  • They are also stamped with an identification number to distinguish them from other robotic mowers.

So you can rest assured of the security features installed to protect your mower from theft and vandalism.

robot lawn mower
Image Credit: Foto-Sabine, Shutterstock

How Long Does it Take a Robot Lawn Mower to Mow?

The time it will take a robot lawn mower to cut a lawn neatly depends largely on battery power.

However, other factors also come into play:
  • The shape of your lawn: If your property is on a slope, the robot will take longer to finish the cut.
  • The total area it has to cover: Robot lawn mowers move slowly due to the size of their blades, so if you designate a large area for mowing, it will take more time to travel to each corner.
  • Growing season: During rainy seasons, when grass grows more rapidly, the mower will take extra hours to go through the entire lawn.

Can a Robot Lawn Mower be Used to Mow Multiple Lawn Sections?

Robotic lawn mowers are not designed to work on different segments automatically.

However, there are ways to use a robot to mow a lawn split into sections:
  • First, you need to cover all the cells with a boundary wire.
  • Put up an extra charging station in each area. This will let the mower work continuously and charge at required intervals.
  • Balance the mowing schedule for each section.
  • The more drastic measure is to buy a second robot lawn mower and split the task.

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What are the Benefits of Using a Robot Lawn Mower?

Below are some of the perks of investing in a robot lawn mower.

It Saves Time

Freeing time spent mowing your lawn is probably what entices one to buy a robotic mower. The most laborious task is the laying of a boundary wire and taking care of the initial installation, which is mostly done once. From this point, the robot will do the rest of the mowing task independently without further input from you.

If you invest in a model fitted with an edge-cutting blade, you save yourself the occasional manual trimming required if it’s a traditional lawn mower.

A Better and Healthier Lawn

Mowing is a continuous exercise when you have a robot maintaining your lawn. A regular cutting means a mulching effect, where the grass clipping is left on the ground to decompose. Organic fertilizer for your yard gives it that bright green look. And if you are worried about the grass cuttings being left on the property, you can rest assured that Robot lawn mowers cuttings are finely done so that you will not notice them.

Furthermore, the weeds will not have any opportunity to spread across the lawn.

robotic lawn mower in the garden
Image Credit: Piotr Wawrzyniuk, Shutterstock

They are Safer

Mowers with larger blades that are lifted higher from the ground occasionally hit debris away from the device at high speed, which can cause injuries. They also threaten the mowing blade’s breaking, severely injuring the operator or anyone close to the mower. It means you must constantly look for mechanical failure and movement around the lawn.

On the other hand, a robot is much safer than a classic mower. It has automated safety measures designed to protect everyone. If a robot lawn mower approaches a big obstacle, it relays on the high-tech sensors to avoid collisions. A robot lawn mower’s most crucial safety feature is the automatic power shut down when it tilts to onside or lifted. Also, you can schedule a robot lawn to run when no one is at home to prevent accidents.

Low Maintenance

Robot lawn mowers require less maintenance than traditional machines that require regular filter changes and oil and gas refills. You only need to clean the underparts with a brush once a month. The other form of maintenance is a seasonal blade change which is easy to do and ensures the battery has a charge.

Consumes Less Power

A robot lawn mower uses lithium-ion batteries to store charge. From this power, they can mow for more than one and a half the time it takes to charge their batteries. Compared to other electrical mowers that require a constant connection to a power source, your robot mower consumes power more efficiently and thus is economical and environmentally friendly.

robot lawn mower in the garden
Image Credit: AntiD, Shutterstock

It Does Not Require a Big Storage Area

Storage is a non-issue when it comes to a robot lawn mower as you don’t need to put up a garage to store it. Simply leave it at the charging dock to have its battery full for the next day’s mowing.

What are the Drawbacks to Using a Robot Lawn Mower?

No mower is perfect, and a robot mower is no different. For all its futuristic promise, it has a few drawbacks that might deter one from investing in one. So before you go out and purchase one, consider the following:

Most Do Not Mow Up to the Edge

Depending on the type of robot lawn mower you own, you will need an extra mowing tool to do the edges manually, as most do not mow up to the edge.

A robot lawn mower is designed for safety first, meaning the edge of the blades and outer body have greater distance. This margin leaves a strip of uncut grass at certain corners or around obstacles on the lawn.

However, you can remedy this by laying stones at the same level as the lawn soil lawn so that the robot lawn mower can have ground to drive on at the end of your yard. You can also invest in a more advanced robotic mower with edge mowing features though this will cost you more.

robotic lawn mower
Image Credit: UlfsFotoart, Shutterstock

Boundary Wire Issues

Boundary wire will usually last long when installed correctly. But outside factors may influence this longevity, such as rodents biting at the wire and breaking it.

Some of the ways to avoid boundary wire breakage include:
  • Ensure you have done the installation correctly. Place the wire at the proper depth to avoid accidental cuts by the mower.
  • Check for any damages to the insulation. When the covering layer is damaged, it will let in moisture, corroding the wire and eventually breaking.
  • If the cable is not buried, set the mower to a higher cutting level to avoid harming the wire.
  • If you don’t have budget restrictions, you might opt to invest in a safety cable that is bite resistant and will also protect against hammers and shovels.

It Takes Time to Set up

You will not achieve the desired look until a few cuts, due to how a robot lawn mower is designed. Each mow cuts a few inches of the boundary you have set. Therefore it will require more rounds and time to get results like a classic mower, but the end result is worth the wait.

Problem Navigating Wet and Sloped Lawns

A robotic mower’s ability to deal with an inclined surface is one of the critical things to look at before buying one. These capabilities vary depending on the model of the mower, and you may even find some with a four-wheel feature to help with very steep slopes.

Even if you get the slope mowing ability right, when coupled with wet conditions your robot may slip and cut lower than the set height. Due to downhill momentum, mowers working on inclined lawns also need an extended zone to avoid skidding over the boundary cables.

robotic lawn mower on the grass
Image Credit: JohnKruger, Shutterstock

Set up Time and Initial Cost

As with any technology, a robot lawn mower will cost you the purchase and installation costs. Not only is this exercise expensive, but it will also take a lot of your time to get it right. A poorly installed cable will be prone to accidents and breakages, which will end up costing you on repair and maintenance.

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FAQs on Robot Lawn Mowers

Can a Robot Lawn Mower be Used to Create Stripes?

Robot lawn mowers move in random patterns since they use the boundary wire to guide them against obstacles. They also do not have rollers like the classic mowers to create stripes.

Do You Need to Cover a Robot Mower?

Robot lawn mowers are built for all-weather and do not need to be covered. The only ask from manufacturers is that you protect the deck from long hours of direct sunlight.

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Robotic mowers have changed how we do lawn maintenance. With a robotic lawn mower, all the hassle of mowing the lawn is a thing of the past if you are ready to make a substantial investment.

A robot mower will do your lawn mowing all season quietly and with minimal to no intervention. Of course, that’s not to say it is all smooth sailing, but we feel for the convenience it gives you, it is well worth it.

Featured Image Credit: sylv1rob1-Shutterstock


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