HOLD for drones

[OrxataEnFartons]

Sorry for abusing the forum but if I am going to find something to comment or suggest it will be these days that I am working with this.
Just a suggestion.
I would like to send instructions to the drones to hold, or wait. Concretely, I could receive also a number representing the number of seconds to keep on hold, or a -1 to keep holding until a continue arrives.
I see there isn't a command for that (HOLD stops the whole simulation), I guess that because the simulator was not addressed to drones originally. So I thought: what if I send a SPD acid 0? I tried, I don't get any error but the drone keeps advancing at least at: CAS/TAS/GS: 126/159/159 kts M: 0.253

I can think of an evil way to get it, that is starting a loop with a MOVE constantly resetting it in its current position during the requested holding time. But it would be nice to have the possibility to cleanly stop it with the SPD,

Regards.

[ProfHoekstra]

Dear Miquel, Only limits to speed are due to the performance model, but I would think the rotor models do allow for speed 0. Best regards, Jacco Hoekstra On 20 Sep 2022, at 16:46, Miquel Angel ***@***.***> wrote:  Sorry for abusing the forum but if I am going to find something to comment or suggest it will be these days that I am working with this. Just a suggestion. I would like to send instructions to the drones to hold, or wait. Concretely, I could receive also a number representing the number of seconds to keep on hold, or a -1 to keep holding until a continue arrives. I see there isn't a command for that (HOLD stops the whole simulation), I guess that because the simulator was not addressed to drones originally. So I though: what if I send a SPD acid 0? I tried, I don't get any error but the drone keeps advancing at least at: CAS/TAS/GS: 126/159/159 kts M: 0.253 I can think of an evil way to get it, that is starting a loop with a MOVE constantly resetting it in its current position during the requested holding time. But it would be nice to have the possibility to cleanly stop it with the SPD, Regards. — Reply to this email directly, view it on GitHub<https://urldefense.com/v3/__https://github.com/TUDelft-CNS-ATM/bluesky/discussions/425__;!!PAKc-5URQlI!85OxU9ZLWitJnSNelw6l4WPxAG8sSvGom-dNR0Xs1tCGEY6l3PV881MlUJJXFVqeADP3bh8e39ZEfIy0eSV-x1GW2KFxkg$>, or unsubscribe<https://urldefense.com/v3/__https://github.com/notifications/unsubscribe-auth/ABWT2BEJMSIUW5YJ3GYYE43V7HE3LANCNFSM6AAAAAAQRE3YYM__;!!PAKc-5URQlI!85OxU9ZLWitJnSNelw6l4WPxAG8sSvGom-dNR0Xs1tCGEY6l3PV881MlUJJXFVqeADP3bh8e39ZEfIy0eSV-x1HBbVGm9w$>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[jooste]

Hi @OrxataEnFartons,

If I start out with the example scenario you've shown in an earlier discussion and add the following:

00:02:00.00>M6001 SPD 0
00:02:40.00>M6001 SPD 38.8;M6001 LNAV ON

The drone correctly slows down to 0, and speeds up again forty seconds later. Could you give a scenario example where this doesn't work?

[OrxataEnFartons]

Hi all,
Soooorry! I sent an edit of the post yesterday a while after publishing it asking you to delete it because I realized I was using a B737 and not a drone model. I found no option to delete my post. So Jacco is right, if it is a multi-rotor model it stops completely.

About keeping it in hold for a while, the plugin I am working on is to connect Bluesky with a UTM server. During the execution of a scenario, the UTM could send separation instructions to the drone, so I don't know the instructions beforehand to add them to the scn.
Then, to restore the speed after a holding time I started using a threading.Timer and that worked well; but I just realized we have the DELAY command which is perfect for that:

restore_cmd = "SPD " + traf.id[idx] + " " + str(traf.gs[idx] * 1.94384)
stack.stack("DELAY " + str(cmd["wait"]) + " " + restore_cmd) #cmd["wait"] contains the holding time

Thanks!

[jooste]

Indeed! DELAY is much more suited, especially since threading.Timer relates to real (wall) time, whereas DELAY is simulation time. If you ever want to run your simulation in fast time it will still work as expected with DELAY.

[OrxataEnFartons]

Good point! Never thought of that. Thanks!