Gender
Male
About
Location
Bedfordshire
About Me:
I'm a graduate engineer and for many years I've been involved in guidance, navigation and control studies for research branches of the UK military.
Please tell us a bit about your UAV interest
I'm no longer involved with ther UK military and recently I've becomes interested in autopilots for small UAVs since (a) they sound interesting and (b)I might be able to "pull through" some of my military background into the civil field.
Hometown:
Maulden
Activity Feed
"Hi MarcS
You make some good points in your comment; I'll try to deal with them in turn.
Firstly, you are correct - the scheme does involve model identification followed by parameter calculation.
I too have seen university dissertations where the…"
You make some good points in your comment; I'll try to deal with them in turn.
Firstly, you are correct - the scheme does involve model identification followed by parameter calculation.
I too have seen university dissertations where the…"
"Hi Andrew
In my blog post I didn't make it clear that my baseline design envisages a flight to capture data followed by processing on the ground. We therefore seem to be thinking along similar lines though you don't say whether you envisage…"
In my blog post I didn't make it clear that my baseline design envisages a flight to capture data followed by processing on the ground. We therefore seem to be thinking along similar lines though you don't say whether you envisage…"
Last August I posted a blog "New offer of help with tuning PID loops" putting forward the idea of applying control doublets to a fixed wing aircraft in flight and using the responses to capture stability derivatives and decide autopilot gains. At…
"Mike
I'm not quite sure what you are saying. Do you thinbk I should have put my most recent offer of PID tuning somehwre else? If so, where?"
I'm not quite sure what you are saying. Do you thinbk I should have put my most recent offer of PID tuning somehwre else? If so, where?"
I suspect my first method for tuning PID loops was not a great hit because it required 3-view drawings or photos of the aircraft plus inertia data all of which is a bit fiddly. I've now got a new method based on flying the aircraft and logging…
"Jonathan
Many thanks for your insightful comments - they are very useful.
I'm best-equipped to generate numbers for reasonably conventional aircraft - high-ish aspect ratio wings, reasonably slim fuselage. That said, I can deal with more "novel"…"
Many thanks for your insightful comments - they are very useful.
I'm best-equipped to generate numbers for reasonably conventional aircraft - high-ish aspect ratio wings, reasonably slim fuselage. That said, I can deal with more "novel"…"
"Following my offer of help in tuning PID loops, Michael Smith posted a couple of very sensible questions:-
Q1. What inputs would need to be supplied by anyone wanting to take up my offer?
A1. I have pre-designed various flight control PID loops and…"
Q1. What inputs would need to be supplied by anyone wanting to take up my offer?
A1. I have pre-designed various flight control PID loops and…"
"Jonathan
With respect, I think you are opening up a can of worms by trying to estimate wind speed. (1) there will be wind gusts on top of the steady wind that will add noise in the 0-1 Hz freq band. (2) where the plane is instantaneously pointing…"
With respect, I think you are opening up a can of worms by trying to estimate wind speed. (1) there will be wind gusts on top of the steady wind that will add noise in the 0-1 Hz freq band. (2) where the plane is instantaneously pointing…"
"Hi Gabriel
I'm interested in your lateral loop PID tuning issues so feel free to get in touch any time."
I'm interested in your lateral loop PID tuning issues so feel free to get in touch any time."
"Jonathan
I've updated my mini-UAV simulation to look at your problem.
My simulation incorporates the following PIDs:-
rudder from y-accelerometer
aileron from roll
roll from heading
and I added a proportional heading from Xtrack loop.
This full…"
I've updated my mini-UAV simulation to look at your problem.
My simulation incorporates the following PIDs:-
rudder from y-accelerometer
aileron from roll
roll from heading
and I added a proportional heading from Xtrack loop.
This full…"
"Jonathan
Would seem strange to use "+=" and reset when a simple "=" would do.
Anyway, getting back to your original query, now I know the basic error correction algorithm, I'll do some experiments with my simulation and get back to you."
Would seem strange to use "+=" and reset when a simple "=" would do.
Anyway, getting back to your original query, now I know the basic error correction algorithm, I'll do some experiments with my simulation and get back to you."
"Hi Jonathan
Since my last post to you, I've done a bit more research and I found a very brief write-up on "Cross-track error correction" in the APM manual. I think I've reconciled it with the code you sent me but, in doing so, I've come up with more…"
Since my last post to you, I've done a bit more research and I found a very brief write-up on "Cross-track error correction" in the APM manual. I think I've reconciled it with the code you sent me but, in doing so, I've come up with more…"
"John
Thanks for the feedback but can I ask a couple of supplementary questions to do with crosstrack error?
You use a quantity called "target_bearing" - is that relative to the plane "now" and based on GPS co-ordinates? If not, then what?
Your…"
Thanks for the feedback but can I ask a couple of supplementary questions to do with crosstrack error?
You use a quantity called "target_bearing" - is that relative to the plane "now" and based on GPS co-ordinates? If not, then what?
Your…"
"John
Sorry if this is a stupid question but have you decided the missions you want your planes to perform? Its the missions that will dictate the PID loops you need.
If your question relates more to PID gain values, I'll need a dimensioned 3-view…"
Sorry if this is a stupid question but have you decided the missions you want your planes to perform? Its the missions that will dictate the PID loops you need.
If your question relates more to PID gain values, I'll need a dimensioned 3-view…"
"Frederick
I do plan to write up my method for PID tuning but other commitments mean it may not be anytime soon.
"
I do plan to write up my method for PID tuning but other commitments mean it may not be anytime soon.
"
"Jonathan
I'd like to help but first I need to understand a bit more about your setup. Does it go something like this:-
Xtrack=>Xtrack PID=>(heading)=>Nav roll PID =>(roll)=>servo roll PID =>(aileron)?
If not, then what?
At the risk of deflecting you…"
I'd like to help but first I need to understand a bit more about your setup. Does it go something like this:-
Xtrack=>Xtrack PID=>(heading)=>Nav roll PID =>(roll)=>servo roll PID =>(aileron)?
If not, then what?
At the risk of deflecting you…"
