Robotic Mowers 101
Robot Lawn Mower Basics
Robots aren’t confined to the realms of science fiction. Believe it or not, the first robotic lawn mower debuted in 1995.
Thanks to improvements in technology, along with changing consumer tastes, lawn robots are now more widely available and affordable than ever.
However, as common as automatic lawn mowers are becoming, you still might have some important questions before you buy one.
Why Robo Mowers Are Awesome!
Robotic mowers are small, battery-powered machines that measure about two feet in length. They use an electric motor and internal computer hardware to trim your grass in a completely different way from traditional mowers.
One difference you’ll notice is the frequency of mowing. Previously, you might have planned to use your traditional push mower every Saturday. In contrast, as long as your automatic lawn mower is powered on, it will mow your lawn every day (or as often as you set it) for a fresh, well-kept appearance.
As a result, you’ll see a robomower use a different style of mowing. You shouldn’t expect a robot lawn mower to create stripes on your lawn or to tear large sections of each blade of grass as a rotary blade mower would. Instead, a robomower will clip small portions of each blade for a uniform look across the lawn.
Because robotic lawn mowers are too small for a collection bag, they leave those small clippings on the ground. The clippings serve as fertilizer and return nutrients to the ground, which can improve your lawn’s health.
However, the biggest difference is the need to program your mower. Don’t let this part scare you. You won’t need an engineering degree to do it. In fact, think of it more like setting your microwave.
However, instead of pushing buttons to heat up your leftovers, you’ll turn dials, push buttons, or press numbers on a keypad to set details specific to your lawn:
- The time of day you want your mower to operate
- The size of the area your mower should mow
- The height at which you want to cut your grass
How Do Robotic Lawn Mowers Work?
As smart as autonomous lawn mowers are, they don’t automatically travel toward patches of long grass. Like children, they need you to set their boundaries.
To set a robot lawn mower’s path, you need to install the guide wire included with your mower along the perimeter of your yard and along the edges of any areas you don’t want to mow (for example, a garden).
The wire can be laid on top of the ground, where it will lie close to the grass’s shallow roots. It is then held in place with stakes, making setup easy to finish within a couple of hours.
You also can dig a shallow trench for the guide wire. This takes more time, but it places the wire out of the way so that people are less likely to trip over it.
Many robotic mowers can be programmed to cover a certain distance in one session – for example, a quarter acre. Once the guide wire is in place, the automatic mower will mow a course starting along the boundary wire and continuing in straight lines until it has mowed the equivalent of the programmed distance.
Advanced robot mowers have built-in GPS capabilities. GPS allows a robomower to create a map of your lawn for even more mowing finesse – for example, for starting in different sections of your yard each time it goes out.
When the mower’s battery is low, the mower will travel back to its docking station so that the battery can charge. If its battery drains before it has mowed your entire yard, it will recharge and then finish the job.
The docking station should be positioned close to the guide wire on a flat surface near an electrical outlet where it can be plugged in. A dry spot such as the space under a deck is ideal.
Always check your mower’s user manual; some recommend that the docking station be placed in a covered or sheltered location at the edge of your yard, such as a shed.
Will a Robotic Mower Work on My Lawn?
If a robotic mower is a purchase you’re considering, there are three details regarding your lawn that you should keep in mind:
- The size of your yard
- The type of grass growing
- The degree of your ground’s incline
- Objects and obstacles in your yard
Just like walk-behind lawn mowers, robotic mowers come in a variety of sizes that make them better suited to handling different amounts of terrain.
Larger robomowers are capable of mowing medium to large properties up to 1 1/4 acre on a single battery charge. Smaller robomowers are better suited for lawns 1/4 acre and under.
Type of Grass
Unlike traditional mowers that use propeller-shaped rotary blades to cut grass, robotic mowers use smaller blades fastened to a rotating drum underneath the mower to clip the grass instead of tearing it.
Cool-season grasses such as Kentucky bluegrass, which tend to be thinner, thrive when cut with a robotic mower. Warm-season grasses such as bermudagrass are thicker but still can grow well when cut regularly.
The takeaway is that robomowers work best when they’re allowed to run as intended: every one or two days, cutting the grass to a height between 1" and 3 ½". Frequent and regular use allows them to clip even thicker bent grasses (although robotic mowers aren't recommended for wet grass).
Ground Slope and Incline
Robotic mowers have a strong advantage over walk-behind mowers when mowing a hilly yard: you don’t have to use your strength to push them!
Depending on the model, automatic mowers are suitable for mowing ground with inclines up to 30 degrees. Always check the incline recommendations for your mower before using it on a hill.
Also note that robomowers require much lower slopes close to the guide wire. Boundary wire should not be placed on ground with an incline greater than 15 degrees.
Yard Objects and Obstacles
Robotic mowers do have sensors that can detect large objects in their paths, such as lawn furniture and trees. For safety reasons, keep pets and small children away from the lawn while the mower is operating.
Robotic mowers cannot detect common small objects that might be left on lawns:
- Pine cones
- Pet toys
- Garden tools
- Pet waste
Remove small objects like these manually before your mower begins mowing.
Automatic mowers also have difficulty traveling over tree roots and bumpy, uneven lawns. Consider rolling your lawn before installing your robotic mower.
Are Robotic Mowers Safe?
Manufacturers understand that automatic mowers present safety concerns for many users. However, your smart lawn mower has features that were designed with safety in mind:
- Emergency stop buttons
- Object sensors
- Blades away from the edges
- Automatic shutdown
- Theft protection
Emergency Stop Button
One of the most reassuring safety features found on robotic mowers is an emergency stop button that requires only a simple push to operate. The large button is found on the back of the mower.
As mentioned earlier, sensors built into the mower detect large objects in the mower’s path so that it can stop and change direction. This includes children and pets, although to ensure their safety, you should keep them off the lawn while the mower is operating.
Instead of the long, propeller-like rotary blades that walk-behind and riding mowers use, a robot lawn mower uses small blades secured to a rotating drum beneath the mower’s body. These blades don’t extend as far as rotary blades.
Many models of robot lawn mower will stop running automatically if they reach too steep an incline or if someone picks them off the ground.
Robomowers can be lifted from the ground, but features like these keep them from being carried away by thieves:
- An alarm that sounds when the mower is removed from the boundary area
- A physical security key that needs to be inserted and turned to shut off the alarm
- A PIN that needs be entered to program the mower
How Do I Take Care of a Robotic Mower?
Because robotic mowers don’t have gas tanks to fill or oil to change, they require low maintenance.
Aside from cleaning grass clippings from the body (always turn off your mower before cleaning it), the most important maintenance task you’ll have to take care of is changing the blades every one to two months due to the frequent mowing schedule.
Depending on the model, changing the blades can be as easy as unscrewing the old blades from the drum and fastening the new blades in place. Follow the instructions in your mower’s user manual for changing the blades.
The Future Is Now
Many homeowners want a great-looking lawn but are unable or don't want to mow themselves. Hiring a lawn care service is an option, but the recurring expense might not be practical.
Thanks to advances in robotic mowers, homeowners don't have to give up a ton of money and time to have a healthy, attractive lawn. The affordability and ease of use of robotic lawn mowers can make that a reality today.