Steve,
I agree it is safer to have the return spring. I think when tuning, it might be useful to be able to set the throttle and leave it when you are tuning the steering rate controller so that the speed is constant and only the steering is being changed as you experiment. Otherwise, having the spring is probably a good idea. I’ll probably leave mine as is, though.
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Wow! What a day! Thank you @SJohnson for helping with all the craziness I created on my mower! Here’s a link to the e-stop I used!
We resolved:
Firmware gremlin (not a rover, but is now; 4.5.1)
GPS Yaw config ( including getting GPS1 back from the dead, and troubleshooting my labeling)
Radiomaster reconfig for single (not r2d2) gymbal steering
Radiomaster switch config to mark waypoint
Servo tune (on jacks) low/high speed
Interestingly, one of my massive servos went kaput at the end. Ugh. Ordered another pair (just in case both are affected). Will force me to paint my push rods. . .
My cousin showed up and joined the fun! He has a Toro 48” in a similar config. If @Swebre2023 hosts another Mowstock, we’ll bring his and mine out!
Really, I can’t thank Steve enough for coming by and pushing me up to the line (dang servo), and everyone else who contributes to this amazing group!
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That servo failure was very puzzling. We took care to make sure it was operating well inside its operating range and any mechanical stops. It just seemed like some sort of infant fatality. Certainly was unfortunate. However, Cris is now pretty much ready to tune the mower. All the necessary systems are now operational (except for one servo).
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Abuse on your end, or possibly flawed product?
I’m very curious about the longevity of those servos.
Great update! Sounds like you and Steve made great progress!
I am interested in how those big servos do also. I have almost lost another of the AGFRC 125kg-cm ones. It is vibrating, but still working. I already had a spare that I will put on when I decide the current one has had enough, but I may be looking for another type.
Cris, I had mentioned to you about the manual steering exponential function now available on Rover V4.4 and later.
Steering expo can be applied using the [MANUAL_STR_EXPO] parameter.
This is used to decrease transmitter steering control sensitivity around neutral.
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Thanks for sending that Steve - I’ll be working on my RC transmitter for a bit while I wait for the replacement servo. Just updated the EdgeTX firmware and wow - way easier than what was shipped. Hope you get one of these Radiomaster rigs - so capable.
I guess I’ll have to get the tractor/shredder out for a bit longer…hehe
While you’re waiting on parts, definitely look into enabling Yaapu telemetry on that Radiomaster radio. You won’t regret the time investment.
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Hey Cris, I just wanted to mention to you that I end up using several of these “Universal” automotive relays. I just use the PWM relays to control them just to get the ability to handle up to 30 amps.
https://www.amazon.com/dp/B0748F1JK4?ref=ppx_pop_mob_ap_share
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I use similar. Combo of digital relay boards and RC relays, but all of them just control higher current standard automotive relays (either the ones within the mower’s own electrical system, or some that I have installed for various subsystems).
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Moved my electronics to a different box that has a bit more room. Mounted my gps cards vertically, and plan to install a fan. Not sure if I’ll have EMF issues, but the cleaner install makes me happy. Happymodel folks are walking me through troubleshooting my servo. No gear issues, but the motor shaft seems to spin inside the helical drive gear (no bueno). I’m continuing to troubleshoot with them - impressed with their tenacity! Still no new servos received - maybe next week…
Working my GPS yaw and have a question - the documentation says measure from the center of the rover to the offset location. Seems to me we got mine working at Mowstock and just measured between the 2 antennas. My heading is a little off, and I’m getting the 65000 error in the Mavlink GPS2 yaw counter. What did we do to resolve that?
Thanks all - hoping to mow shortly after that servo shows up!
And, my battery monitor started working…?
Well, it looks like you have several things going on and you are getting into an area where everything has to work and every detail matters. I would be expecting GPS1 to be showing RTK Fixed and GPS2 to at least be showing RTK, since it gets a correction straight away from GPS1. I would check out that GPS antenna wire we were having trouble with when I was there. Until you can get RTK Fixed on both units, noting else is going to work. Make sure they have a good view of the sky (clouds can cause problems at times also). Check to make sure the GPS units or the wiring is not mixed up. If GPS1 still shows RTK with no base station input, something is mixed up. I am not an expert on GPS systems and I was one of @Yuri_Rage’s worst students, but in all the struggling, I have always been able to get them working.
One thing that complicates the setup on your mower is the fact that your GPS antennas are not mounted in a simple symmetrical geometry with respect to the IMU (flight controller). One is more forward of the IMU and the other one is a different distance behind the IMU. Left and right their distances to the IMU are also different. Then there is the height up and down (if they are level with each other it is easier). In your case you will have a different elevation for each one.
Use the WIKI information on getting the spacings correct.
https://ardupilot.org/rover/docs/common-sensor-offset-compensation.html#common-sensor-offset-compensation
Being close doesn’t count, if that final antenna spacing is off more than fractions of a centimeter (in 3 dimensional space), it is not going to work. When we tested the GPS systems at MowStock the antennas where level on the ground and placed at the correct spacing. We had RTK Fixed on both.
I would make two assumptions (which might be controversial, but it is the way several of us have set these mowers up).
- Assume the center of gravity (for a mower) and center of rotation are the same and is located (left and right (Y axis) and front to back (X axis)) at the center between the rear tires on a Zero-Turn mower.
- Assume that the IMU (located in the flight controller) defines the elevation (up and down (Z axis) of the center of rotation.
Hope this helps, but it does take some time to check and double check every detail.
Will do Steve - thanks as always…
And, my battery monitor started working…?
Well, I have installed and tested the back-up remote control kill switch I mentioned before. My RC transmitter and receiver are my first line of defense, but I wanted a second layer of safety. below is the unit I am going with for now. It is a 433 MHz gate opener type transmitter/receiver designed for a working maximum working range of 300 meters. I tested my unit installed on the mower at 120 meters (a typical viewing distance I operate from), with the mower operating cutting grass and the shutdown switch worked perfectly every time I actuated it. It was a clear line of sight and I used an external gate opener antenna on the receiver that let me move the antenna away from the actual receiver. I mounted the receiver in one of my enclosures (because it is not water tight), unscrewed the small dipole antenna on it and installed an external antenna connected with a short piece of cable using the SMA connector.
There are 2 of these units out there which look very similar. One is rated for 300 meters and the other one is rated for 1500 meters. The longer range one had a bigger transmitter that would not be as convenient to fit in a shirt pocket. I actually bought both units and have experimented with both a bit and the transmitters are interchangeable if paired up to which ever receiver I was using. There is a pairing process and privacy codes involved to keep each 433 MHz radio from triggering the switch. I think the main difference between the 2 models is a bigger transmitter (more milliwatts of power transmitted) in a bigger case with a bigger battery. Since the smaller unit worked fine for my application, I just stuck to the pocket size transmitter. I wired my receiver directly to my mower’s battery (through it’s own dedicated fuse) and it stays connected 24/7. This way I don’t forget to turn it on. I measured the current drain of the receiver at 30 milliamps. I will likely end up putting a battery disconnect switch on the battery later on for periods when I am not using the mower. It should be noted that the receiver does not provide an open and closed contact. It provides switched 12V power to control an external relay.
I would expect that every installation will be a little different due to different RF noise environments and equipment configurations. Like @Yuri_Rage said these are cheap products and caution is advised. In my case a plan to actuate the switch each time prior to starting the mower to make sure it is still operational.
300 meter range
https://www.amazon.com/dp/B09B6MRMNL?ref=ppx_yo2ov_dt_b_product_details&th=1
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Good luck getting the advertised range outta those guys. And technically 433MHz requires an amateur license in the US.
Great idea overall - I just hope it doesn’t let you down at a critical moment.
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Unlicensed use of 433 MHz gate openers is authorized by the FCC under Part 15 These devices have to be approved by the FCC prior to sale. The transmitters use very little power, and they are only broadcasting power for the brief second you depress the button to actuate the switch.
All that being said, these products are being made in China and probably not FCC approved, and who knows how much power they are broadcasting. That is part of the reason I went with the smaller pocket sized transmitter.
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Belt AND suspenders! Nice to hear it’s working Steve! My relay bank showed up today!
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Servos arrived today!