Lawn mower time lapse. EcoFlow Blade Review: Great robot mower, for very specific lawns

Piecing Together an Auto Mowing Rig

There are about 8 months from spring ’till fall in southeastern USA where the grass grows at an ever increasing rate, eventually outpacing even the most avid outdoorsman’s desire to jump on a lawn mower.

This simple fact, combined with both a Rapid fall of hardware component and a steady refining of history altering open-source autopilot stacks, means that many passerby have begun seeing sights previously uncommon to man.

In this blog post we’ll introduce the main components of our mowing rig. In future posts — hopefully not 2 years from now — we’ll try to flesh out some more system details. As always, feel free to post questions in the Комментарии и мнения владельцев and I’ll try to address anything I haven’t explained well.

The Pursuit of the Perfect RTK GNSS System

As we’ve previously discussed, for several years the long poll in the hardware tent hamstringing our autonomous mower dreams has been centimeter-level robust GNSS gear 1.

2 years ago we marveled that ComNav had built a precision GNSS module for ~1000 USD capable of positioning to within 1cm at 10hz (i.e. 10 readings per second — or a new position output every 0.1 seconds). Our excitement was justified because the big agriculture/surveying GNSS vendors were concurrently exacting perhaps 5-10x that price for similar technology.

It is with considerable excitement we report that now in 2019, your affordable autonomous field-navigation robot dreams are more approachable than ever.

The reason for this, of course, is largely the gift that u-blox has recently introduced to mankind: the ZED-F9P L1/L2/L5 GNSS module.

If you live thousands of miles away from Switzerland like me, then you may also shamefully admit that your knowledge of that beautiful country has hitherto been effectively limited to the following:

Well sister, get ready to add a 4th item to that list:

Who are u-blox and why do they matter?

u-blox is a Swiss publicly traded, highly profitable, growing, financially healthy, dividend paying fabless chip designer that is quietly introducing a line of low-cost ultra high precision GNSS modules that will likely change the entire world 2.

Over the past 20 years, u-blox has been developing an ever improving line of high performance GNSS receivers that have become the de facto standard GNSS component in several important markets.

If you’re not very familiar with the world of drones here’s a way to think the place u-blox occupies in that market:

u-blox really is that dominant as the provider for drone GNSS receivers, and it’s reasonable to speculate that they’ll soon provide the high precision GNSS modules onboard a big percentage of the ~70 million automobiles annually sold worldwide.

Many more glowing words could be accurately penned about u-blox, but our task at hand involves using their ZED-F9P high precision GNSS module as the position solution for an autonomous mower.

So what’s the big deal with the ZED-F9P?

In laymen’s terms, the ZED-F9P allows any outdoor thing to know it’s exact position on the face of the earth to within ~1cm with up to 20 position updates per second at a price-point that’s an order of magnitude lower than similarly robust incumbent solutions.

It does this for a flat one-time price of ~500 USD. That price is for 2 ZED-F9P modules (along with 2 antennas) to build a stand-alone system (i.e. one of the ZED-F9P modules is set up as a Base Station / “correction” provider). If you have an existing correction source, then you’ll only need to purchase one module, and so your cost is halved to ~250 USD.

The fine citizens of Precision Ag / Land Surveying world, arriving at this page and reading the ZED-F9P specs and pricing, will likely have a visceral appreciation for the u-blox accomplishment that perhaps few others can fully understand 7.

For 500 you can purchase a 2 receiver / 2 antenna (a capable active patch antenna is included in the dev kit) L1/L2/L5 multi-constellation 20hz system that’s comparable in performance (and arguably much more approachable in terms of ease-of-integration) to a 10,000 system from one of the existing old school RTK manufacturers.

Readers familiar with RTK technology jargon may be interested in a flyover of the ZED-F9P’s technical specs:

ZED-F9P Technical Highlights

Price: ~250 USD 3

Multi-Constellation: GPS / GLONASS / Galileo / BeiDou — In other words, it’s processing position signals from satellites from all 4 of the major GNSS constellations.

Multi-Frequency: L2OF, L2C, E1B/C, B2I, E5b, L1C/A, L1OF, B1I — This is the real kicker — historically you have only obtained multi-frequency receivers by parting with thousands (or ten-thousands) of USD dollars.

20HZ output capable: Stated differently, just to be clear, it can give you 20 unique cm-level accurate positions every second.

Well-documented and mature presence: i.e. autonomous autopilot stacks (such as the gold-standard Ardupilot) have supported u-blox gnss receivers for years 4.

Supports standard RTCM corrections.

Low power consumption.

If you’re coming from the world of Precision Ag or Land Surveying and you read those specs, due to your experience with the companies that have supplied that market for 2 decades, you may be thinking “yeah but how much does The Man charge me for software un-locks for all 4 constellations, multiple frequencies, and 20HZ output?”

Yes, the ZED-F9P comes with all those features out of the box — the only catch I know of is our shared inability to stockpile these modules and then time-travel back to 2015, making a fortune through resale.

Rover Build

The rover we’re describing today is built on a repurposed electric wheelchair powertrain as we’ve previously detailed. But note that we’ve upgraded a few components since the previous discussion about this rover.

The significant modifications are these:

• Replace our beloved ComNav K501g with the superior u-blox ZED-F9P.
• Upgrade rover Wi-Fi system with Ubiquiti mesh network 5 (i.e. we run a Ubiquiti access point on the the rover that’s joined to our local Ubiquiti network. This offers many benefits, for example: it’s now trivial to shell/VNC into rover’s onboard Raspberry Pi from any computer on our local network).
• Replace Pixhawk 1 autopilot with Pixhawk 4 autopilot. Just to be clear, this is not because the Pixhawk 1’s functionality is yet significantly outdated for this application (even though Pixhawk has been around since 2013) — instead, when Holybro introduced the Pixhawk 4 I got curious about it’s performance, and liking it’s specs (and Holybro’s solid reputation) but not finding many user reviews of the module, curiosity overtook and I just bought the little guy from Sparkfun.

Mowing Deck Build

We hacked together a mowing rig 6 as follows:

• After eyeing the big 60″ deck on our old Scag mower, we cut out a similarly-shaped (albeit scaled-down) hexagon from 1/8″ sheet metal.
• Procure 3 24v 150W ZY6812 150-GM150115 DC motors from eBay (somehow those powerful motors are shipped to your door @ 25 a pop).
• Hook up some shaft coupler extensions (from eBay) to the DC motors. This buys us a couple extra inches of clearance between the mower deck and the blade disk. Note that I had to Loctite the nuts that snug these extensions to the motors. Also note that if you want to purchase extra nuts for this extension (for example, if you want to hold those Honda disks in place by sandwiching the blade disk between two nuts), that the nut size ia a little odd: M10 Left Hand 1.5. This Amazon query should get you what you need.
• Bolt the 3 DC motors to mowing deck sheet metal.
• Attach Honda blade disks to the shaft coupler extensions. I like the Honda disks because they’re metal (and because they’re Honda). I had to drill out the hole in the center of the disk slightly — i.e. you have to make the hole’s diameter a little bigger to use the shaft coupler extensions that we’re using.
• Ask Pops to weld together a carriage structure to attach to the rover. If you study carefully the metal and swiveling wheels on this structure you may recognize they’re just parts we’ve salvaged that were laying round from prior power-chairs.
• Suspend the mowing deck from the carriage by 4 loops of 1/8″ galvanized 7×19 steel wire cable (this ultra-strong wire rope was leftover from building the backyard containment fence a few years back). Those aluminum brackets attached to the deck that the cables loop through were laying around the shop.
• Run ground wire and fused 24v power wires back to the mowing deck.
• Create mower deck sides by bending cutting sections of 3″ Aluminum flat bar. Bolt aluminum sides to deck using these brackets.
• Bolt two Spiderman bicycle training wheels to front left/right sides of mowing deck — this helps the deck to “float” along without getting hung up on uneven terrain.

Wrapping Up

Let’s bring this post to a close with two time-lapse videos (one run — but video taken from 2 cameras — note that the second camera’s battery died before run completion) taken this morning.

Note the number of obstructions that would challenge an RTK system of lesser capability.

The mowing rig works quite well, keeping the back yard neatly trimmed and letting my clothes stay clean in the process.

June 27, 2019 update — Here is my current Ardupilot Rover Pixhawk 4 param file for the rover: Pixhawk4-Rover-Params

• While it’s true that random-pattern electrically fenced autonomous mowers have been around for the last few decades (i.e. Husqvarna / Robomow), the advent of low-cost robust cm-level positioning will likely enable similarly-sized mowers to maintain an order of magnitude more land while discarding the pain point of installing/repairing an electronic perimeter. Additionally, the idea of autonomous-mower-as-a-service becomes much easier to imagine.
• The financially savvy readers of this blog may note that u-blox accomplishes this and more (i.e. they also play in the hot IoT cellular / Bluetooth space) while presently trading at an unusually reasonable multiple of ~14 times earnings (note, for instance, they’re quite similar in metrics to Axon (police camera / Taser manufacturer) but they trade at 1/10 the price (relative to earnings) of AAXN).
• 250 USD (as of May 2019) is the price for the official development kit (called C099-F9P) that you can pick up from Digi-Key. A handful of companies have built maker-friendly boards based on the ZED-F9P including ArduSimple, Sparkfun, Drotek, and CSG Shop. The bare chip retails for ~140 USD (as of May 2019).
• Ardupilot ZED-F9P support (as of May 2019) happens via the standard NMEA driver. In other words, the last time I tried to use the Ardupilot custom u-blox driver linked above with the ZED-F9P, it didn’t appear to be working (in contrast, that driver works wonderfully with the old u-blox NEO-M8P L1-only RTK module). To be perfectly honest I didn’t debug the u-blox driver at all (and hence of course what I’m saying here should be taken with a grain of salt) since it was easy to just enable standard NMEA position output in the ZED-F9P.
• If you’ve not yet converted your home/office network to Ubiquiti, perhaps that’s a more pressing item than anything else in this little blog post. The glittering reviews are justified — Ubiquiti really is that good.
• Readers without tolerance for the hackfulness of this mowing rig should have their spirits buoyed by Mr. MowerProject’s outstanding efforts (often accompanied by slick CAD images) in this area.
• Emlid appears poised to further their reach into the Land Surveying market via their new Reach RS2 based (ostensibly) on the u-blox F9 chips.

EcoFlow Blade

The EcoFlow Blade robotic lawnmower will save you a lot of trouble this summer, given you’re willing to handle the cost and have the right kind of lawn.

With many appliances becoming Smart every year — often needlessly — it’s refreshing to see a lawn mowing solution that would save homeowners hours per week. EcoFlow specializes in portable power stations, solar, and other Smart devices, and the Blade is its first attempt at a robotic lawnmower.

Coming in at just under 3,000, the Blade has many features built in to stand the test of many seasons chopping grass. With LiDAR obstacle avoidance sensors, wire-free boundaries, route planning, and a 10-inch cutting distance, it’s perfectly made for people with medium-sized and flat lawns.

EcoFlow Blade. Setup and app

Out of the box, the EcoFlow Blade comes with the mower itself, a power adapter, a GNSS antenna, the charging station, cables and pegs, and other accessories for setup. Setup, ideally, is the most difficult part of using the Blade.

To start, determine where you want to put your charging station and connect it to your nearest outdoor plug. From here, the GNSS antenna should be installed in a good spot, around 7 feet from any trees or walls. The guide included in the box as well as the video series EcoFlow has made, are helpful. In fact, we recommend watching the tutorial videos before purchasing to verify if the mower is for you.

Now, before securing everything in place, install the EcoFlow app, and it’ll guide you through connecting to your Wi-Fi, measuring signal strength, and getting started on mapping out your lawn. You may have to move around the antenna or charging station to find the most optimal spot for the mower to work.

At this point, you should fix the charging station on the ground using the screws provided. It’s also important to hold down any wiring on the lawn with the supplied pegs to prevent the Blade from cutting its power source.

As for mapping out the property, ensure you are thorough and patient in this process, as it can take some time. However, it’s worth it if you want the Blade to get into your lawn’s nooks and crannies.

The app is well-designed, and you can adjust all the appropriate settings, such as deck height, automated mowing times, volume, and more.

EcoFlow Blade. Connection issues

Our testing of the Blade was severely limited by the characteristics of our lawn, impacting connection and use.

EcoFlow warns on its website that potential buyers should review the online checklist to see if their lawn is compatible with the Blade. The checklist asks for your lawn size, tree height, tree shadow area, and whether you have multiple lawns.

If you have tall trees, large lawns, or multiple ones spread far apart, EcoFlow does not recommend the Blade and tells users to Stay updated with news on the next-gen mower. This is all to say that our lawn had too many nearby trees and too many slopes to be an ideal testing ground for the Blade.

Firstly, the mower appears to struggle at slopes greater than 5-10 degrees, making the nearly 45-degree hill in our front lawn an impossible task.

The trees in our backyard proved difficult when installing the GNSS antenna, so we had difficulty maintaining a stable connection. Extreme measures were taken as we attempted to put the antenna on our roof to ensure a better connection, but these efforts did not help.

EcoFlow Blade. Lawn mowing and performance

That said, the few times the Blade worked, we saw a good performance. It mowed our backyard in around twenty minutes on quiet mode, with the mowing deck adjusted to 3 inches. The quiet mode worked extremely well but went slower than others. We recommend this mode if you have the Blade scheduled in the mornings or evenings.

The app allowed us to fully map and mow our backyard with almost perfect accuracy. Upon reviewing a time-lapse, it appeared that the Blade missed a small spot, but this could also be chalked up to human error since the user must draw out the mowing area by remote-controlling the Blade. The remote control from the app can make it difficult to properly map certain corners or details on a lawn with more complex features.

However, the quality of the mowing was good, and the automation that the Blade brings makes it easier than ever to stay on top of grass cutting throughout the seasons. The deck can adjust between 0.8 and 3.0 inches, so we recommend you cut your grass to size before implementing the Blade into your lawn care setup.

The Blade has an IPX5 water resistance rating, making it easy to clean the bottom with a hose. This also helps it survive rainfall, but the Blade has a rain sensor to return to the charging station if it rains in the middle of a cut to prevent damage or improper mowing.

The Blade’s omnidirectional wheels aid its movement on the grass. However, that makes it a bit cumbersome to manually drag the Blade back to the charger during a disruption.

The Blade will call out if it hits a slope that’s too high or bumps into something it cannot navigate. Ensure the mowing route is always clear before activating the Blade, and keep animals or children off the lawn.

Progress, but for a limited demographic.

Even if you don’t have many Smart appliances or automation in your home, we think the Blade can be used by anyone who fits its demographic. Although, this demographic is limited to homeowners with flat, medium-sized lawns with minimal trees.

It’s a small audience, but we can imagine the time and energy saved by transitioning to a robotic lawnmower is enormous on a yearly scale. It’s exciting to see the robotic lawnmower industry come to life, and we look forward to reviewing the technology as it develops to become more reliable on different types of lawns.

EcoFlow Blade Cons

Where to buy the EcoFlow Blade Robotic Lawn Mower

The EcoFlow Blade retails for 2,899 and is available on Amazon and via the EcoFlow store. There’s a 200 discount in effect at both retailers at the time of publication.

As with many in his generation, Thomas Sibilly’s first Apple device was a hand-me-down second-generation iPod Touch. Growing up deeply embedded in Apple’s modern ecosystem stoked his love for technology, leading him t.

GoPro Waterproof Time Lapse Box

I searched the Internet high and low for something to mount my GoPro camera too, in order to shoot extremely long term time lapse footage. I had ideas of converting a trail cam box, to just attaching the camera to a tree. The latter was just asking for me to get my camera stolen.

After weeks of searching and no luck, I decided to build my own. It is not only waterproof, but secure and safe as well. here is how I did it.

Step 2: Find a Box

First I order a Pelican 1120 box from Amazon. The most expensive part of the build, but also the main part as well. (About 30)

Step 3: Find a Lens Adapter

I then ordered a 52mm lens adapter for the camera. I also went to Amazon and found one that came WITH a UV lens and a couple extra filters. mainly for protection more than for their intended purpose. (About 12)

Step 4: Cut a Hole for the Adapter

I then used a utility knife to cut a square hole in the box, small enough a to barely squeeze the adapter through so that it would snugly fit without glue. I then used marine waterproof caulk to seal any gaps.

Step 5: Drill Holes to Attach Mounting Hardware

In my situation, I was mounting my camera to a 2.5 square pipe. Therefore, I turned the box over and drilled holes into the existing mounting screw areas. Picked up a couple U bolts and slipped them into place. (5)

You could just as easily drill these holes and mount a metal bracket to be used as a mounting device.

Step 6: Build Mounting Base

In order to mount the camera to the box, I needed raise the platform inside the box. I wanted to be able to close the lid and have the camera FLUSH with the adapter. I used a 1×6 piece of pine and cut it to fit inside the box. I Drilled the holes through the back to allow passage of the u bolts. This wasn’t quite deep enough, I still needed about an 1/8 raise to get flush. I used a scrap piece of plywood that worked perfectly.

I then used the mount that came with the camera. It’s the one that actually held the camera in the box attached to the cardboard box for display. I drilled a few holes and used some washers with wood screws to keep it in place.

Step 7: Cut Passage for USB Cable

Next, I drilled a couple holes in the bottom of the box and then used a utility a knife to square up the hole. All to be able to pass the USB cable through.

When it was finished, I used the marine grade caulk to seal the hole up.

Step 8: Purchase a Dummy Battery

Which brings me to why I need the hole.

I purchased a Switronix DV-GP3 GoPro battery adapter. It replaces the actual battery (which has a very short life span) it has a USB attachment and provides constant longer power to the camera from a car battery. (~23)

In my case, I used an old lawn mower battery and put it in a battery box from a boat.

When you use this adapter, the standard door to the GoPro case will not close. You will need to use the one with the rectangle openings in the top and bottom. My camera came with this extra door.

Step 9: Purchase a 12V Converter

Now, In order to hook it up to the battery, you will need a power converter. There are hundreds out there. I chose a Dual 2 USB Port Power Charger Socket 12V 1A 2.1A Outlet. (15) It’s made for motorcycles and works great. Hook it straight up to the battery, then hook the camera battery to the USB port.

Step 10: DONE

Hook everything up and test it out.

I also attached 2 Master Locks to try to keep out unwanted fingers.

If you desire longer than 1min intervals in your Time Lapse, you need to use this EASY hack from Konrad Iturbe. chernowii.com

Select your camera and follow the directions.

Комментарии и мнения владельцев

Great setup. Looking to do something similar for the build of my house. Curious if you would share a few things:

What size memory did you use and how often did you have to download and clear it?

Did you use any type of scheduler to try and reserve power and memory at night?

I used a 32g card ( all I had at the time) I actually used 2, replaced the full one with a clean one.

I checked it more times than I technically needed to. But it seems that the camera kept turning itself off. I don’t know if the neighbors were unplugging the battery or if the camera itself had a glitch, but it was annoying. So I checked it about every other day or so. But when it worked, I think it took 10,000 photos if I’m not mistaken, before it would become full. Easy math will tell you what you can get out of a card. Just take a couple practice shots at peak day and at night when its black.

The peak day will of course be larger, but the night time black pictures will be very small. You should be able to calculate from there.

I did not use a scheduler, but I did contemplate using a program you can install on the camera that will let you take shots at any increment you desire. But after loading it in and messing with it, I realized for my purpose, I would not need anything other than the program made with the camera.

Mower Traffic Stress

I have walked countless properties with homeowners during service visits to their lawns, and one of the questions I’m asked frequently is, “If your company is taking care of my lawn, where are these bare spots coming from?” The question is often posed after we have strolled past several seemingly random bald patches of lawn here and there. “Is this disease? Do I have grubs? Is it because the technician is dripping chemicals from his spray gun?” While these lawn issues in question have the potential to cause damage to the grass, none of them cause the grass to disappear suddenly.

So how have small areas of the lawn disappeared? The answer is often far simpler than you would think. The good news is that there’s no additional treatments needed to combat this particular lawn pest. The bad news is that the monster gobbling up portions of your lawn may in fact be you!

It’s Common Sense

When you see a bed of flowers or shrubs, is your first impulse to drive over them? Of course not! You could potentially damage them. Yet, one of the most basic practices employed by every homeowner since the dawn of suburbia involves driving a mower (or at the very least pushing a heavy, wheeled implement) on top of the thousands of plants that comprise our lawns. However, we expect these plants to hold up without consequence to the regular mower traffic, when the machines weigh several hundred pounds.

Don’t worry I’m not suggesting that you shouldn’t mow the lawn, or that you should expect the quality of the lawn to suffer a great deal after every cut. What I am telling you though is not to expect the relatively fragile living ecosystem that is your lawn to hold up to mower traffic indefinitely.

Wear and Tear

The damage typically caused by mower traffic is two-fold; there is the wear caused by the frequent traffic over the same areas over and over, and the tear caused by the mower wheels physically tugging at the plants.

Have you ever noticed the depressions that develop in the road where car tires ride over it day after day? This same depression effect occurs as a result of mower traffic in the lawn, and soil compaction issues develop. In central New Jersey we have clay soil, and while it doesn’t mean you can simply pick up a handful of it and start sculpting, it does mean that when it is wet it’s softer and more easily compacted. Once it dries, as you would expect clay to, it hardens in its compacted state. This process repeated over and over causes the already microscopic pore spaces between the soil particles to become non-existent. Once the pore spaces are gone the soil becomes impenetrable to water and oxygen, which is a bad thing for the grass plants. The longer this process goes unchecked, the more compacted the soil becomes, and the more the lawn suffers. Like the road, the lawn becomes worn out very gradually, so immediate damage is not evident for years.

The effects of long-term mower stress can be seen in the lower portion of this image where the lawn has been worn away in two parallel spots by the continuous mower traffic through the same path.

You can, however, sometimes see short term effects from compaction. If plants are already suffering under extremely hot or cold weather conditions, you can see streaks develop along mower tracks in the lawn due to the additional compression stress. While the lawn generally recovers from this, it helps to highlight the fact that there are consequences to mower traffic.

The image above shows temporary stress from machine traffic that occurred following frost.

The second type of mower stress is the tear caused by traction of the tires. As the mower makes turns, the tires pull on the plants and can sever their stems or uproot them altogether. If the lawn is mowed following heavy irrigation or rainfall, the soil is easily torn up by the tire traction and can cause ruts. This type of stress is certainly more evident, and something that most homeowners try to keep from happening. However, this too can be very subtle. Minor ruts in the lawn that happen every now and again can add up over time. It isn’t until several small injuries accumulate that the homeowner takes notice.

The images above show damage to the lawn that has been caused by mower tear. However, the diagnosis is hard to make given the vantage from which it is being viewed and the time that has lapsed since the most recent cut.

So, What’s the Solution?

To avoid damage that may develop from compaction caused by mower traffic, it is imperative that the lawn be core aerated on a regular basis. For most residential lawns, core aerating every-other-year should be often enough to keep the soil compaction from becoming an issue. Also, if there are areas that stay wet due to poor drainage, they should be addressed professionally by a landscaper to resolve this problem. Areas such as these become damaged exponentially faster than well-drained areas and core aeration will most likely not provide ample correction on its own.

Also, avoid mowing the lawn when it is saturated or following a heavy storm. Homeowners with in-ground irrigation should also consider their watering schedule and set irrigation to run as far from the mowing schedule as possible. For example, if the lawn is typically mowed on Mondays, irrigation should be run on Tuesday or Wednesday so that the maximum amount of time lapse occurs between heavy watering and mower traffic.

Though it may sound obvious, seed the damaged areas. It is a great practice to go through the lawn at the end of each summer and spot seed the lawn as necessary. This keeps small damaged spots from being able to accumulate over time.

Finally, try to avoid creating narrow sections of turf in your landscape designs. Mowers are forced to traffic the lawn in the same pattern regularly through these bottle-neck areas, causing the grass to wear away quickly. If you must have narrow passages between landscape beds, these should have some other alternate ground cover in place such as gravel, stone paths, or low-lying shrubs. Long-term turf growth should only be expected to occur with reasonable maintenance in well drained areas of the property that are fully exposed to the sun.

Conclusion

There is wear and tear that occurs as a result of nearly every regular practice developed by human beings. Just like brushing your teeth or jogging each morning, with mowing the benefit outweighs the consequences that may come as a result. Your lawn care specialist may point out to you that mowing the lawn has contributed to some turf loss in your lawn. Luckily, there are some simple best practices that can help reduce mowing stress to the turf.

If you are in our service area and have questions about possible mowing damage or mowing best practices, please give our office a call at 908-281-7888, or request an estimate.