I would suggest Manual, Auto, and guided if you are just using a a 3 position SW. there is a way to get six modes using another radio channel. I don’t have a spare radio channel so I just stick to 3 modes. Manual needs to be at the top so when the SW is up you are in manual position to start out with. I find the guided mode useful sometimes to lead the mower around with the computer.
In response to a few questions I’ve received… @Ger_H @Jan_Hacek @Matt_Angilley
For blade motors I use these
from Chongqing Yurui Agricultural Machinery Sales Co., Ltd. https://cqyr.en.alibaba.com/minisiteentrance.html?spm=a2700.details.cordpanyb.2.9e321d13q4s0om&from=detail&productId=1600620146469
For blade motor controllers I’m using Flipsky FSESC FLIPSKY Mini FSESC6.7 PRO 70A base on VESC6.6 With Aluminum Anodized H (Make sure you isolate these speed controllers from your flight controller otherwise you’ll fry one of them!!!)
For traction motors I’m using these 63100 140KV Sensored Version Brushless Motor for Electric Skateboard s – Dongguan Freerchobby Co.,Ltd 80Kv model
For traction gearboxes the Neugart PLE 80 PLE - Neugart USA Corp.
For traction ESCs benjamin vedder’s VESC 6 controllers VESC 6 75 (Make sure you isolate these speed controllers from your flight controller otherwise you’ll fry one of them!!!)
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Thanks for sharing, Chris! I’ve been curious what’s under the hood. Quite the chore to find compatible hardware at decent prices, and I’m sure this will help some folks.
Hey Chris, I have always wondered if anyone has taken a Ryobi or Ego electric zero turn mower and put an Ardupilot setup on it? I figure you know what is going on in the electric mower universe. The consumer electric mowers I’ve seen look way underpowered to do big mowing areas. I was just curious about what people have done in this area.
Don’t have any insight to that, sorry
Is the centre of gravity for the zero turn mower:
a) where the diagonals from wheel to wheel cross, or
b) middle of the rear axle?
I am asking because of the weird results Yuri got here:
I think it should be b)
I have done all the tuning as far as I can tell.
I reset the servos to standard.
I inverted the right servo direction in the MP servo settings.
What should the emergency stop kill? E.g., run away mower?
a) kill the engine, thus mower stop
b) kill all power (also kill the flight controller)
c) something else
I also noticed that the mower points in the opposite direction on the map in MP. I swapped the GPS antennas for a quick fix, still the same, as in no change of direction.
Center of the rear axle. Again, you’re referencing a post that has been overcome by events with code fixes.
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Should I not read this stuff then? Seems to get me into trouble…
I have changed the INS_POS* values to reflect centre rear axle.
The GPS, after I drove the mower, is now pointing into the right direction.
After driving the mower for the first time after resetting the drive servos, the throttle response is still squishy as in smooth rather than responsive. However the steering response is now proper; not sure what changed it.
Also, what should the emergency stop kill? E.g., run away mower?
a) kill the engine, thus mower stop
b) kill all power (also kill the flight controller)
c) something else
I haven’t thought much about it, but figured if I use the ignition switch to shut down the engine; hence, mower, and the flight controller, this is not helpful; meaning, the flight controller should be switched on|off with a different switch.
What approach are people using to do this?
You are learning with a bit of trial by fire. So…read more! The follow on posts on the most recently referenced topic discuss a bug fix.
E-stop is a subject with many opinions, most of which are correct. It all comes down to philosophy.
My take:
A physical e-stop button/switch should kill everything. Stop it dead. Now.
RC enabled safeties should include mechanisms to switch to hold mode, disarm, and kill ignition. Those do not have to be simultaneous, and they are listed in order of severity of response.
A separate wireless safety relay should also be employed. It should, at a minimum, kill ignition. There are lots of key-fob based products with relay modules that can be wired in series with onboard circuits.
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fair enough…
Yes, can agree with that. Also easy to implement. (Engine to ground and interrupt power, as most e-stop switches have a NO and NC.)
Back to the squishy/lagging throttle… where can this be set?
The current effect is, if I let go of the throttle (so it centres itself = neutral), the servos don’t bounce back to neutral, but leisurely go to neutral, meaning the mower can run over the intended stop by 10 metres (depending on engine throttle).
Is the over damped throttle response in ACRO or MANUAL mode?
Just coming back from ‘testing’…
This sloppy throttle response is gone when engine revs are increased (say 60%)… (was so far testing in idle)… recall to having been in ACRO mode.
I went through the tuning, and most values didn’t need changing.
I did piddesired and pidachieved, which was fine.
Cruise was learned.
Can this tuning graph be played back?
As it is difficult to watch the graph while also watching the mower not to run into things. It currently has a tendency to move slightly to the right.
A log file would tell the whole story. Mission Planner has a “Dataflash Log” tab for that, but teaching log review is probably beyond the scope of this thread.
Double check that you still get the snappy response expected in MANUAL mode. Unless you mis-programmed the servos to reduce the slew rate, that should be the case. The stock slew rate is very rapid.
Assuming the servos have not been accidentally mis-programmed, sluggish response in ACRO mode indicates a poor tune. It’s usually either an ATC_SPEED_P term that is too low or an ATC_SPEED_I term that is too high (causing wind-up).
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Agree… read up on it, and was greeted with Error:System.TimeoutException: Timeout on read - GetLogEntry Looks like the log files are too big. … and time out after 10%-ish.
I have to rip out the flight controller as I didn’t not cater for “frequent” SD card access (given I can update the firmware remotely.
I am not easily scared, if at all, but seeing this mower running around is a concern ATM, until I trust the tech I guess.
Automated equipment can be dangerous if you are not in control even when it is running on its own. My approach is to put enough safe guards in place so I feel comfortable. Anyone who has operated this type of machinery will experience things you did not expect (usually cased by yourself) so literally you have to protect yourself from yourself.
I have crash buttons on each side of my mower and an RC controlled emergency cut-off switch (which has been used a few times). I have also the throttle and the blade control automated so I don’t have to get near the mower once I am ready to rev up, turn on the blades and mow. My RC cut-off signal does not go through the flight controller. I was able to pick off the PWM signal right at the RC receiver bypassing the flight controller. You also have to make sure you stay in range for your RC transmitter to reach the mower. Failsafes can be used to insure the radio is still connected.
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Hello
Your project is amazing! I’m Erik from Brazil, and I’m still starting my studies on the lawn mower, and honestly speaking, I have no knowledge about the pixhawk, I’m looking for projects on Youtube and I saw that many use this device for control.
I would like to know if you have a diagram of the electrical connections and the components needed to assemble an autonomous lawnmower. So to have a better idea, to acquire these components and start my tests. Thanks for the posts
Welcome to the challenge.
Like it or not, start reading the https://ardupilot.org/rover/docs/gettit.html is the best approach. I can tell from experience, that I thought, well, get the equipment, plug it together spend a few hours putting some values in others have already figured out and the mower will mow your lawn. — Believe me, this is not how you will succeed.
The documentation will tell you all about the equipment, what you need, why you need it, how to put it together and how to tune it all. There are so many things that need to be understood; and there is no way around it, no short-cut, unless you have it built by someone else.
You will need to understand safety, fail-safe, some mechanics, how GPS works, electrical wiring, remote controllers, receivers, flight controllers, memory, SD cards, firmware, MissionPlanner, technical understanding, some physics and maths, it is not as easy as most have initially thought (including myself).
Check some of the mower builds and videos from the builders and what they are talking about. If you do not understand it, this is where you need to learn.
In any case: all the very best on your journey.
BTW: the documentation will have wiring diagrams; but every mower hardware is different (one way or the other).
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Hey, Eric welcome to the Ardupilot website. There is much information to be found here in automating about anything that will move. I have had particular interest in the automated zero turn mowers and it has been a huge learning experience and a lot fun. As a bonus I have made many friends from all over the world all interested in automating mowers.
I agree with Max, the Introduction to Rover — Rover documentation is a great place to start and I would also recommend reading the earlier posts on this thread discussing the flight controllers (we use processors generally meant for aircraft) people are using in the mowers. Best gear for starting ArduPilot Mower - #4 by SJohnson
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I agree with you 100%, thanks a lot for the link. I really know I need to learn more about. In any case, the team here can help me with questions.
Thanks again for your attention!
Steve Johnson.
Thank you for your attention, and I hope to be part of this team! Thanks for the links