Author Topic: RF module hunting  (Read 19634 times)

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Offline aaronhance

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Re: RF module hunting
« Reply #50 on: February 13, 2016, 09:22:33 pm »
Woops, yeah good eye. :)
 

Offline uncle_bob

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Re: RF module hunting
« Reply #51 on: February 13, 2016, 09:50:00 pm »
Woops, yeah good eye. :)

Hi

Do *not* ask how long I spent comparing those numbers to the WiFi frequencies before I figured that out :)

Bob
 

Offline hendorog

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Re: RF module hunting
« Reply #52 on: February 14, 2016, 05:41:20 am »
I did mean dBm yes, sorry :P.  As for auto tracking, I've already said in this post I'm doing that. I've also said that I will be using the high gain antenna for rx not tx. Thanks!

Its pretty easy to manually track a high gain antenna when the target is a long way away - the angle the antenna needs to move for a distant target which moves 1000m is much smaller than the angle for a close target moving 1000m.

Point the high gain antenna in the direction you are going to fly and just fine tune it if you need to.

Use diversity and a more omni antenna to handle when the UAV is close. The diversity will switch back to the high gain antenna when you are far away enough to get a better signal.

Use an autopilot to ease the workload.

I used to attach the antennas on my FPV goggles and just moved my head to aim it. Prior to that I used a screen with antennas mounted on a tripod.

This is all standard stuff in the FPV world from a couple of years ago when the regulations around the world were less restrictive about long range FPV.
 

Offline aaronhance

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Re: RF module hunting
« Reply #53 on: February 14, 2016, 02:23:50 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P
 

Online tggzzz

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Re: RF module hunting
« Reply #54 on: February 14, 2016, 04:20:58 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #55 on: February 14, 2016, 06:57:34 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.

So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/
 

Offline hendorog

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Re: RF module hunting
« Reply #56 on: February 14, 2016, 07:03:21 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

Sounds like a plan. The general guidance on diy fpv has always been to introduce one thing at a time - i.e. get the thing flying before adding the autopilot, then add telemetry/OSD, then video, then antenna tracking, etc etc.
I found that easier anyway as you get to have some fun at each stage.

If you haven't found it yet, fpvlabs.com is a great resource - that site was created because at the time every FPV discussion on rcgroups degenerated into an argument about the rules... Sound familiar?? :)
 

Online tggzzz

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Re: RF module hunting
« Reply #57 on: February 14, 2016, 07:08:55 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.

So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Since we have no idea how it behaves and misbehaves w.r.t. the ANO, we cannot answer that. Neither, I presume, can the OP.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #58 on: February 14, 2016, 07:51:42 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.

So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Since we have no idea how it behaves and misbehaves w.r.t. the ANO, we cannot answer that. Neither, I presume, can the OP.

Yep he can - because he has to satisfy this clause:
"The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made."

He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The UK rules state no aerial work without approval, which would have put the police on the wrong side of the law. Interestingly, over here they have taken a different approach, based on the actual risk instead of the use.
 

Online tggzzz

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Re: RF module hunting
« Reply #59 on: February 14, 2016, 08:45:34 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.

So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Since we have no idea how it behaves and misbehaves w.r.t. the ANO, we cannot answer that. Neither, I presume, can the OP.

Yep he can - because he has to satisfy this clause:
"The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made."

1) since he hasn't built the autopilot yet, he can't answer the question.
2) after he's built it he might provide a response, but whether or not that is a correct answer w.r.t. the ANO is a different kettle of fish

Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

Given that the OP is interested in a 5 mile range, it is reasonable to question how effective (or even safe!) any tether might be - always presuming a drone could lift it in the first place.

Quote
The UK rules state no aerial work without approval, which would have put the police on the wrong side of the law. Interestingly, over here they have taken a different approach, based on the actual risk instead of the use.

The UK rules state far more than that, and it it the other more basic rules that caught out the Mcr police.

Why does someone displaying an antipodean flag think they know so much about the UK ANO?
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #60 on: February 14, 2016, 09:38:17 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.

So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Since we have no idea how it behaves and misbehaves w.r.t. the ANO, we cannot answer that. Neither, I presume, can the OP.

Yep he can - because he has to satisfy this clause:
"The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made."

1) since he hasn't built the autopilot yet, he can't answer the question.
2) after he's built it he might provide a response, but whether or not that is a correct answer w.r.t. the ANO is a different kettle of fish


1) Correct - I should have said 'He _will_ need to be able to satisfy this clause'
2) I haven't seen any rules around development of UAV's in the UK. I gather you know better so please share your knowledge.
2a) Do we know the size of craft the OP is developing?

Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.
Given that the OP is interested in a 5 mile range, it is reasonable to question how effective (or even safe!) any tether might be - always presuming a drone could lift it in the first place.

Did you really think I was suggesting a 5 mile tether...?  :-DD

Quote
The UK rules state no aerial work without approval, which would have put the police on the wrong side of the law. Interestingly, over here they have taken a different approach, based on the actual risk instead of the use.


Quote
The UK rules state far more than that, and it it the other more basic rules that caught out the Mcr police.

1) I agree they do have other rules. I never said otherwise. It was just an observation that the new NZ rules, which have recently been updated, now work differently.
2) OK, thanks for the info.


Quote
Why does someone displaying an antipodean flag think they know so much about the UK ANO?

I haven't stated anywhere that I do. I'm just trying to help him complete his project which is about a subject which interests me and which I have experience in.

On the other hand you have told the OP he is going to go to prison before he has even started.

If you know something about small UAV development then by all means provide some _useful_ guidance.
 

Online tggzzz

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Re: RF module hunting
« Reply #61 on: February 14, 2016, 10:26:16 pm »
Hey, I'm building the autopilot system myself, software and hardware, although I will be using GPS and rf modules. I might as well build an auto tracking antenna, not that hard to get two angles from gps cords and elevation. I have a second person helping me on this project, but he's still learning the basics of programming. :P

So you may be getting visits from both OFCOM and the CAA? I wonder which will claim jurisdiction first :)

The CAA have told the police (in Manchester) to stop illegally playing around with drones. The police did stop, pronto.
The CAA have brought prosecutions for drones violating the Air Navigation Order, and the perps have ended up in prison.
So what rule is he breaking by building it himself rather than importing it from China like everyone else does?
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/
Since we have no idea how it behaves and misbehaves w.r.t. the ANO, we cannot answer that. Neither, I presume, can the OP.
Yep he can - because he has to satisfy this clause:
"The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made."
1) since he hasn't built the autopilot yet, he can't answer the question.
2) after he's built it he might provide a response, but whether or not that is a correct answer w.r.t. the ANO is a different kettle of fish
2) I haven't seen any rules around development of UAV's in the UK. I gather you know better so please share your knowledge.

AFAIK there are no rules/laws about developing (nor buying) UAVs in the UK - but that's irrelevant. There are laws about flying/operating UAVs.

I am definitely not going to summarise the law because I could accidentally write something that is wrong or misinterpreted.

Understanding the law will not be trivial; I would recommend joining a local RC club since they will have a better idea. Similarly join a radio ham club to learn how to avoid violating the Wireless telegraphy Act.

Quote
Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.
Given that the OP is interested in a 5 mile range, it is reasonable to question how effective (or even safe!) any tether might be - always presuming a drone could lift it in the first place.
Did you really think I was suggesting a 5 mile tether...?  :-DD

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

Quote
Quote
The UK rules state no aerial work without approval, which would have put the police on the wrong side of the law. Interestingly, over here they have taken a different approach, based on the actual risk instead of the use.
Quote
The UK rules state far more than that, and it it the other more basic rules that caught out the Mcr police.
1) I agree they do have other rules. I never said otherwise. It was just an observation that the new NZ rules, which have recently been updated, now work differently.
2) OK, thanks for the info.
Quote
Why does someone displaying an antipodean flag think they know so much about the UK ANO?
I haven't stated anywhere that I do.

Your memory is defective.

Less than three hours ago you wrote "...because he has to satisfy this clause: 'The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made.'" and "The UK rules state no aerial work without approval".

Quote
On the other hand you have told the OP he is going to go to prison before he has even started.

No, I haven't. I have pointed out that other people have been jailed, and that if he does something illegal in the future he might get a criminal record.

That is useful information that could save the OP a vast amount of wasted effort.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #62 on: February 14, 2016, 11:59:41 pm »

Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

There were two parts to my comment:

He could use a short tether (say 2 metres) to avoid fly-aways so that he could test the autopilot in flight instead of on the bench - e.g. for tuning the PID loops.
For longer flight tests he could use a master RC receiver to take over from the autopilot if it went haywire.

Perhaps over a period of time that information could be used to build confidence that that autopilot was working and therefore can be used safely?

Disclaimer: I am not an expert in autopilot development and the UK ANO.

Quote
Quote
Quote
Why does someone displaying an antipodean flag think they know so much about the UK ANO?
I haven't stated anywhere that I do.

Your memory is defective.

Less than three hours ago you wrote "...because he has to satisfy this clause: 'The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made.'" and "The UK rules state no aerial work without approval".

Ah I see, I was simply sharing potentially useful information which I found using Google.

Those are quoted/paraphrased from this link a couple of posts earlier.
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Ultimately the OP may discover for himself that a 5 mile flight is in the too hard basket legally. That's his call to make. It would require a special effort to do in NZ as well FWIW. Either approval from CAA NZ - which essentially requires $$$ and some process of ensuring safety - or a number of spotters distributed along the flight path.

 
 

Online tggzzz

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Re: RF module hunting
« Reply #63 on: February 15, 2016, 01:52:27 am »

Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

There were two parts to my comment:

He could use a short tether (say 2 metres) to avoid fly-aways so that he could test the autopilot in flight instead of on the bench - e.g. for tuning the PID loops.
For longer flight tests he could use a master RC receiver to take over from the autopilot if it went haywire.

Perhaps over a period of time that information could be used to build confidence that that autopilot was working and therefore can be used safely?

Disclaimer: I am not an expert in autopilot development and the UK ANO.

Nor, it would seem in threat definition, system validation, system development nor system verification.

Start by considering the effects of windspeed, turbulence and windshear near obstacles (ask parascenders and hang glider pilots), the Fresnel zone and other multipath effects (simple physics), GPS non-availability (which happens; there are usually NOTAMS about it), ISM band interference (guaranteed to happen), to name a few off the top of my head.

Next consider how you won't be able to test those with a few tethered flights - except to demonstrate that you haven't got necessary reliability.

If you really want to get into autopilots, I would suggest starting with RC cars or boats. There's less chance of knackering other people with those.

Quote
Quote
Quote
Quote
Why does someone displaying an antipodean flag think they know so much about the UK ANO?
I haven't stated anywhere that I do.

Your memory is defective.

Less than three hours ago you wrote "...because he has to satisfy this clause: 'The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made.'" and "The UK rules state no aerial work without approval".

Ah I see, I was simply sharing potentially useful information which I found using Google.

Those are quoted/paraphrased from this link a couple of posts earlier.
https://www.caa.co.uk/Commercial-industry/Aircraft/Unmanned-aircraft/Small-unmanned-aircraft/

Ultimately the OP may discover for himself that a 5 mile flight is in the too hard basket legally. That's his call to make. It would require a special effort to do in NZ as well FWIW. Either approval from CAA NZ - which essentially requires $$$ and some process of ensuring safety - or a number of spotters distributed along the flight path.

At last you understand. There's no point him wasting 1000 hours,say, of his time only to find out a proper solution (if any is possible) would take 100,000 hours.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #64 on: February 15, 2016, 02:51:45 am »

Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

There were two parts to my comment:

He could use a short tether (say 2 metres) to avoid fly-aways so that he could test the autopilot in flight instead of on the bench - e.g. for tuning the PID loops.
For longer flight tests he could use a master RC receiver to take over from the autopilot if it went haywire.

Perhaps over a period of time that information could be used to build confidence that that autopilot was working and therefore can be used safely?

Disclaimer: I am not an expert in autopilot development and the UK ANO.

Nor, it would seem in threat definition, system validation, system development nor system verification.

Start by considering the effects of windspeed, turbulence and windshear near obstacles (ask parascenders and hang glider pilots), the Fresnel zone and other multipath effects (simple physics), GPS non-availability (which happens; there are usually NOTAMS about it), ISM band interference (guaranteed to happen), to name a few off the top of my head.

Next consider how you won't be able to test those with a few tethered flights - except to demonstrate that you haven't got necessary reliability.

If you really want to get into autopilots, I would suggest starting with RC cars or boats. There's less chance of knackering other people with those.


Are these things you have experience in?

At last you understand. There's no point him wasting 1000 hours,say, of his time only to find out a proper solution (if any is possible) would take 100,000 hours.

Well shucks, a compliment.

 

Online tggzzz

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Re: RF module hunting
« Reply #65 on: February 15, 2016, 09:47:05 am »
Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

There were two parts to my comment:

He could use a short tether (say 2 metres) to avoid fly-aways so that he could test the autopilot in flight instead of on the bench - e.g. for tuning the PID loops.
For longer flight tests he could use a master RC receiver to take over from the autopilot if it went haywire.

Perhaps over a period of time that information could be used to build confidence that that autopilot was working and therefore can be used safely?

Disclaimer: I am not an expert in autopilot development and the UK ANO.

Nor, it would seem in threat definition, system validation, system development nor system verification.

Start by considering the effects of windspeed, turbulence and windshear near obstacles (ask parascenders and hang glider pilots), the Fresnel zone and other multipath effects (simple physics), GPS non-availability (which happens; there are usually NOTAMS about it), ISM band interference (guaranteed to happen), to name a few off the top of my head.

Next consider how you won't be able to test those with a few tethered flights - except to demonstrate that you haven't got necessary reliability.

If you really want to get into autopilots, I would suggest starting with RC cars or boats. There's less chance of knackering other people with those.


Are these things you have experience in?

Yes. All of them, bar one: I haven't used RC aircraft/boats. Some as a professional engineer, some as a leisure activity, some both.

Being sufficiently humble to know what I don't know, I've kept my eyes open over the years, and asked people that do know about RC flying. I try to avoid being an example of the Dunning-Kruger effect, usually succeeding.

What's your experience in these things?
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline hendorog

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Re: RF module hunting
« Reply #66 on: February 15, 2016, 12:32:39 pm »
Quote
Quote
He might do that by tethering after making changes, and/or by having a 'master' RC receiver which can switch out the autopilot for example.

The only way your comment could have been relevant and helpful would be if it was a 5 mile tether. In that light, how should we interpret your comment?

There were two parts to my comment:

He could use a short tether (say 2 metres) to avoid fly-aways so that he could test the autopilot in flight instead of on the bench - e.g. for tuning the PID loops.
For longer flight tests he could use a master RC receiver to take over from the autopilot if it went haywire.

Perhaps over a period of time that information could be used to build confidence that that autopilot was working and therefore can be used safely?

Disclaimer: I am not an expert in autopilot development and the UK ANO.

Nor, it would seem in threat definition, system validation, system development nor system verification.

Start by considering the effects of windspeed, turbulence and windshear near obstacles (ask parascenders and hang glider pilots), the Fresnel zone and other multipath effects (simple physics), GPS non-availability (which happens; there are usually NOTAMS about it), ISM band interference (guaranteed to happen), to name a few off the top of my head.

Next consider how you won't be able to test those with a few tethered flights - except to demonstrate that you haven't got necessary reliability.

If you really want to get into autopilots, I would suggest starting with RC cars or boats. There's less chance of knackering other people with those.


Are these things you have experience in?

Yes. All of them, bar one: I haven't used RC aircraft/boats. Some as a professional engineer, some as a leisure activity, some both.

Being sufficiently humble to know what I don't know, I've kept my eyes open over the years, and asked people that do know about RC flying. I try to avoid being an example of the Dunning-Kruger effect, usually succeeding.

What's your experience in these things?

None of the development items (electronics hobbyist),  some exposure to the aviation items (student pilot in the past and RC), and most of the RF items (RC/FPV/HAM). I'm certainly no expert and don't profess to be one.

The reason I asked that question was that it sounded like you had developed professional UAV's and were therefore approaching the problem from that direction.
My experience is with hobby level equipment which is not verified/validated. Therefore my expectation is that a DIY autopilot would not require that level of rigour either.




 

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Re: RF module hunting
« Reply #67 on: February 15, 2016, 03:06:20 pm »
The reason I asked that question was that it sounded like you had developed professional UAV's and were therefore approaching the problem from that direction.

Definitely not, but I certainly would try to have a professional approach with anything of mine that could kill/injure/affect other people. And UAVs, whether or not they have an autopilot, certainly fall into that category.

The key point is to thoroughly define how things might fail. Amateurs starting in a field usually consider how things might work; the better amateurs go on to develop an appreciation of failure modes. The OP leads me to believe they are an amateur starting in this field and the RF field.

Today's news report, merely the latest of many: http://www.bbc.co.uk/news/business-35577124

Quote
My experience is with hobby level equipment which is not verified/validated. Therefore my expectation is that a DIY autopilot would not require that level of rigour either.

The laws make no distinctions between professional and amateur control systems, for the obvious sound reasons.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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