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Sep 27, 2017, 05:09 PM
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FlyingW's Avatar
Mike,

Yes you are right , I mean the URLS receiver's PWM values out to the flight controller.

In Mission Planner when I turn off the transmitter, the channel positions do not go to the settings presumably recorded by the pushbutton failsafe procedure - they remain exactly where they are at the time I turn off the transmitter.

Once I get the ULRS Rx to play back the failsafe settings, then I will configure the flight controller to react to them appropriately.

Manreg, it's interesting that when I push the button I get the beep and LED pause and you do not and yours works - thanks for the information. I am using a pair of 1W Orange Tx modules, so it is a little different than yours.

Thanks all,

Paul

Interesting Update: I have my receiver RSSI going out in PPM channel 8 as a PWM value to the flight controller. When I turn off the transmitter, the PWM value for channel 8 indeed goes to zero (0). In fact channels 9 through 16 also go to zero, but channels 1 through 8 remain locked at their last known position. I wish I could program the Pixracer to use channel 8 as a failsafe indicator. Note that I am sending only 8 PPM channels from my Futaba 9C transmitter to the ULRS Tx module.
Last edited by FlyingW; Sep 27, 2017 at 06:52 PM. Reason: Update regarding RSSI in Channel 8 and channels 9-16 in failsafe
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Sep 28, 2017, 12:14 AM
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Thread OP
a) Is the failsafe from the ULRS working fine, independently from thePixracer ?

That's an important point, as very few users are on a Pixracer there could be something specific about it.

b) Did you try to use 16 channels, to see if it changes something ?
c) Could you try to use the PPM RSSI output rather than PWM RSSI ? In this way the RSSI value will be sent as a servo value to a selectable channel. This can be used to trigger a failsafe on the Pixracer.
Sep 28, 2017, 04:31 AM
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Hello everyone, does anyone know where I can buy an ulrs mini dolphin board 1w rx, or lrsmax2 rx please? I can't solder it by myself.
Sep 28, 2017, 07:29 AM
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FlyingW's Avatar
Quote:
Originally Posted by flipflap
a) Is the failsafe from the ULRS working fine, independently from thePixracer ?

That's an important point, as very few users are on a Pixracer there could be something specific about it.

b) Did you try to use 16 channels, to see if it changes something ?
c) Could you try to use the PPM RSSI output rather than PWM RSSI ? In this way the RSSI value will be sent as a servo value to a selectable channel. This can be used to trigger a failsafe on the Pixracer.
Flipflap,

a) Independent of the Pixracer, the failsafe of the receiver is not working. The only thing that happens when I turn off the transmitter is that the receiver channels 8-16 go to a PWM value of 0. Pressing the button on the Tx module does not save any of the servo positions for use later as the failsafe positions.

b) How do I try 16 channels? My transmitter only outputs 8.

c) For RSSI I am using the receiver's PPM channel 8 output; I am not using an analog method. I selected this from the ULRS-CC RSSI channel selection feature.

I agree that the RSSI embedded into channel 8 could be a reasonable way to tell the flight controller that a failsafe event has occurred. What Arduplane parameter would be used to watch channel 8 and trigger failsafe? Nothing obvious comes to mind. It would be simple if the receiver put channel three (3 = throttle) to zero - then it could tell ArduPlane use its existing throttle failsafe feature.

Thanks,

Paul
Last edited by FlyingW; Sep 28, 2017 at 07:40 AM.
Sep 28, 2017, 01:21 PM
Just call me Justin.
Hey flap,
Is it possible to get the code you used to put the rssi on an lcd screen from the i2c ports. I Wana try to put it on the 1.0 firmware and display it or use another arduino to do it. Kinda bored and wanted to see if that would be cool to use.
If it's under your closed source, then I understand. No worries....

I've been trying to find a code online about doing the same thing, but I only find little snippets about it. I'm not much of a programmer. What I really want is to have "rxrssi" and flight mode displayed on a 2x16 lcd.
Sep 28, 2017, 03:31 PM
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Thread OP
Sorry but that's part of the closed source.

This said, you should be able to find an Arduino library that will work for your LCD (it will be dependent on the LCD brand as the commands such as clear screen, move cursor depend on the LCD).

Then regarding mavlink decoding, I'm not sure it exists as an arduino library, but have a look at gitsly, it has some mavlink decoding functions. If it's not critical you could even drop the checksum verification and it then becomes quite simple. I wonder if minimosd code could be a place to look too, a priori it has mavlink decoding too.

Here's the basic mavlink packet structure : https://en.wikipedia.org/wiki/MAVLink#Packet_Structure , then every packet type has a different content, but if you're not into development there are many traps so I'd recommend to look at the projects above.
Sep 28, 2017, 03:40 PM
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Thread OP
Quote:
Originally Posted by FlyingW
Flipflap,

a) Independent of the Pixracer, the failsafe of the receiver is not working. The only thing that happens when I turn off the transmitter is that the receiver channels 8-16 go to a PWM value of 0. Pressing the button on the Tx module does not save any of the servo positions for use later as the failsafe positions.

b) How do I try 16 channels? My transmitter only outputs 8.

c) For RSSI I am using the receiver's PPM channel 8 output; I am not using an analog method. I selected this from the ULRS-CC RSSI channel selection feature.

I agree that the RSSI embedded into channel 8 could be a reasonable way to tell the flight controller that a failsafe event has occurred. What Arduplane parameter would be used to watch channel 8 and trigger failsafe? Nothing obvious comes to mind. It would be simple if the receiver put channel three (3 = throttle) to zero - then it could tell ArduPlane use its existing throttle failsafe feature.

Thanks,

Paul
I appreciate your perseverance, I'm more and more inclined to think there's a bug if using only 8 channels. It would be interesting if you're able to test with another transmitter giving 16 channels just to compare.

Regarding the failsafe you're right, it's not possible to arduplane to use another channel than throttle (well if you're crazy you could recompile arduplane with some modifications).

A different approach would be to rely on the GCS failsafe. It will go into failsafe when there's no longer any telemetry. In ULRS as telemetry and RC are sent toghether, if one is missing they're both missing. You'll have to choose a short timeout, maybe two seconds. http://ardupilot.org/plane/docs/apms...-function.html

I wouldn't go for a shorter one second time-out because the mavlink message heartbeat is sent approximately every second. Remember that it will then failsafe as soon as no telemetry is seen, for example if you disconnect your laptop.
Sep 28, 2017, 05:10 PM
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FlyingW's Avatar
Flipflap,

Ok, it is all good and I believe every experience adds to the progress. We slog on.

The GCS failsafe seems like a reasonable way to go. I really want a good failsafe strategy in place to flight test a new integrated RC/Telemetry system.

Another feedback: I had reliability problems with the Mavlink connection while testing ULRS with Mission Planner and the Navio2 flight controller. Now testing with a Pixracer, Mavlink and ULRS have been impressively solid. There must be some subtle differences between the two flight controllers and their serial data handling.

Thanks again,

Paul
Oct 01, 2017, 09:51 AM
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FlyingW's Avatar
Wanted to work on my ULRS this morning, but the Tx and Rx LEDs were not working - only blue on the Tx.

Hooked up the Tx module to ULRS-CC and it looked ok.

Hooked up the Rx module to ULRS-CC and it was bricked.

I was able to reload the software, but am unable to configure the RF channels and RSSI settings, etc on the Change Parameters. After filling in the channels and other data, and clocking on the "Saving Parameters" button, the page hangs forever with the message: "Waiting for a valid version packet."

Please give any advice as to how to recover the Rx.

Thanks,

Paul
Oct 01, 2017, 10:10 AM
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FlyingW's Avatar
...and now ULRS got blown away again by the McAfee program. I'm getting depressed.
Last edited by FlyingW; Oct 01, 2017 at 10:55 AM.
Oct 01, 2017, 11:22 AM
RC fanatic
Quote:
Originally Posted by FlyingW
...and now ULRS got blown away again by the McAfee program. I'm getting depressed.
You could add the folder path to McAfee as an exception and it will not be included in the scan.
Oct 01, 2017, 01:32 PM
Registered User
Thread OP
Quote:
Originally Posted by FlyingW
Wanted to work on my ULRS this morning, but the Tx and Rx LEDs were not working - only blue on the Tx.

Hooked up the Tx module to ULRS-CC and it looked ok.

Hooked up the Rx module to ULRS-CC and it was bricked.

I was able to reload the software, but am unable to configure the RF channels and RSSI settings, etc on the Change Parameters. After filling in the channels and other data, and clocking on the "Saving Parameters" button, the page hangs forever with the message: "Waiting for a valid version packet."

Please give any advice as to how to recover the Rx.

Thanks,

Paul
Does the spectrum analyzer work on the RX ? This will indicate if the RFM module is damaged or not.

How is the module powered up ?
Oct 01, 2017, 04:24 PM
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FlyingW's Avatar
Flipflap,

The spectrum analyzer doesn't work, but that is likely because I cannot program any channels. I cannot save the settings - it just hangs, waiting for some valid packet.

I also tried the other module, used a Tx module and it is dead also. The ULRS-CC cannot recognize it as a URLS Tx or Rx. I found that its configuration was blown away also. With the Tx module ULRS-CC also just hangs waiting for the mysterious valid packet.

Tried both modules on two different PCs, both which worked until a few hours ago.

The Rx Module is powered by a 9.6 battery into the VIN, GND and PPM ports area on the board. The Tx module is powered by the 9.6v source coming from the trainer port of the transmitter.

I think this event first happened when I attempted to hook up to the ULRS-CC this morning. The Tx and Rx seemed to be happily flickering away with both red and blue LEDs while hooked up to my Pixracer. I wanted to verify the RSSI so I proceeded to power down and change connection to the ULRS-CC . When I powered it back up and connected to ULRS-CC nothing worked any more.

Shortly after, McAfee blew away ULRS-CC.

I told McAfee not to worry about ULRS-CC and it is working again, but I think the configs on both the Tx and Rx went away - and the ability to put them back with them.

Thanks,

Paul

UPDATE: Just was able to get the spectrum analyzer output on ULRS-CC for both the Tx and the Rx module. Both the Tx and Rx module's spectrum analyzer trace looks the same.

I can eventually get ULRS-CC to recognize the modules, but neither can be configured - they both want that valid packet.
Last edited by FlyingW; Oct 01, 2017 at 11:24 PM.
Oct 02, 2017, 01:47 AM
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Thread OP
That's not a valid spectrum analyzer graph. The rfm module is likely damaged.

What antennas are you using ?
Oct 02, 2017, 06:36 AM
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mike_o's Avatar

Changing baud rate without acces to USB port?


My ULRS has been working nicely for some time now. I even did a 120km round trip with one of the planes (not connected all the way, just at some critical points, I also had to do some work along the way).

I then decided to move a second receiver to a 1600mm glider, with an APM 2.8 buried deep inside, but I forgot that the APM was set up for 57600baud, not 19200. So no joy, of course. Due to the narrow fuse of the glider, its difficult to access the USB port, so now my question is: Can I change the 57600 setting to 19200 through the telemetry port, which setting I want to change? Kind of like sawing off the branch you're sitting on...


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