Picopilot stripdown on diydrones.

[spitfiremk9]

At last all my susspisions have been confirmed, someone has done a complete stripdown of the U-nav product and compared it with other autopilots now available, they had even GROUND the ID numbers off the chips? I'm no micriprocessor buff, but surely that must have damaged some of them with the vibrations involved in grinding?
What this experiment explains to me is that I paid 800 bucks for rubbish,
It is very refreshing for me to see that we now have a number of better products available and at a lower cost!
Many thanks to all those who took the time to show me this and help relieve my frustrations.

[patrickegan]

I am a little confused about exactly what you are saying…
Are you saying that the Diydrone site has done a totally unbiased review of all of the autopilots on the market or did they just go over to petting the pooch for the “in” crowd? Or are you just stirring the poop?

[spitfiremk9]

No Pat, log on to their website diydrones.com and look for yourself (its free!!) You'l see, U-nav realy had ground off the chip ID's and the boards turned out to be real cheap hobby things aparently, no wonder they were having so many complaints!
Could you enlighten me as to what "petting pooches and stirring poop" has to do with pointing out pertenant facts!

[eddymoore]

I paid 800 bucks for S**t, clearly I was blatantly lied to by their audacious customer services dept.

is not a 'pertenant fact', it's an angry rant, without context. At least provide the link if you're going to create a thread about it.

[rich smith]

I'm curious what percentage of this johnny-come-lately naysayers are competitors sh***ing in their boots? There's no other explanation of their reactions.

Removing numbers is standard method in the industry to protect IP from hackers who like to reverse engineer. I can assure you it has little effect on MTBF.

[ShadesOfGray]

The article is here:
http://diydrones.com/profiles/blogs/picopilot-stripdown

You have to be logged in to view it.

[zlite]

The article is here:
http://diydrones.com/profiles/blogs/picopilot-stripdown

You have to be logged in to view it.

No, you don't have to be logged in. It's open to all.

[Jack Crossfire]

Castle Creations paints over the numbers with lacquer. Shredding the plastic is the kind of enraged thing Hillary would do.

All electronics look like S**t in a year. You'd be surprised to learn there was once something called the Moto Razr. Every middle manager blew $300 of his home equity to have one. It made all other phones look like Pico pilot.

[patrickegan]

The thread is janky, as the junior high kids would say. :(

[tekrunner]

At last all my susspisions have been confirmed, someone has done a complete stripdown of the U-nav product and compared it with other autopilots now available, they had even GROUND the ID numbers off the chips? I'm no micriprocessor buff, but surely that must have damaged some of them with the vibrations involved in grinding?
What this experiment explains to me is that I paid 800 bucks for S**t, clearly I was blatantly lied to by their audacious customer services dept.
It is very refreshing for me to see that we now have a number of better products available and at a lower cost!
Many thanks to all those who took the time to show me this and help relieve my frustrations.


Don't feel bad, I spent 800 bucks for that POS too. Frustration with UNAV is apart of the UAV learning curve.

[ehx]

Well, with UNAV you wonder just how well these guys know their stuff. On their FAQ page, for example, they claim that clouds and rain reduce GPS performance. In reality, the GPS frequencies were chosen precisely because they are NOT affected by weather. There's a big red warning flag. What other technologies are they using that they don't have a complete grasp of?

I'm sure they have some satisfied customers, but some of the things they have done really make you wonder.

[tekrunner]

I'm sure they have some satisfied customers


You wanna bet some money on that? :rolleyes:

[d_wheel]

I see nothing wrong with removing component I.D. in order to protect their corperate interests, and I am definitely NOT a fan of the PicoPilot.

Later;

D.W.

[spitfiremk9]

The thread is janky, as the junior high kids would say. :(

Nonesnse, this thread should be turned into a Sticky!

[patrickegan]

I’d wholeheartedly agree if there was a whiff of objectivity, or possibly a side by side comparison by “someone” with no affiliation to competing product(s). :)

[rich smith]

Overcast has MAJOR effect on dilution figures of GPS. Some units stop working completely when a cloud passes. Pretty obvious who's experienced in this stuff and who's not.

Janky might be an understatment here. Amazing what tricks some will play to promote their projects.


Well, with UNAV you wonder just how well these guys know their stuff. On their FAQ page, for example, they claim that clouds and rain reduce GPS performance. In reality, the GPS frequencies were chosen precisely because they are NOT affected by weather. There's a big red warning flag. What other technologies are they using that they don't have a complete grasp of?

I'm sure they have some satisfied customers, but some of the things they have done really make you wonder.

[mhaun5]

Overcast has MAJOR effect on dilution figures of GPS. Some units stop working completely when a cloud passes. Pretty obvious who's experienced in this stuff and who's not.

Janky might be an understatment here. Amazing what tricks some will play to promote their projects.

Sorry for my confusion but it wasn't very clear to me. Which company is spitfiremk9 associated with in promoting his product against UNav?

Thanks!
Mike

[rich smith]

Sorry for my confusion but it wasn't very clear to me. Which company is spitfiremk9 associated with in promoting his product against UNav?
Thanks!
Mike

Not always companies. Sometimes just religious zealots. Try telling a Paparazzi "enthusiast" that it's hard to get working. Similar with Linux cultists etc. Also note that some tricks involve logging in under different identities to trash competition.

[zlite]

Also note that some tricks involve logging in under different identities to trash competition.

Rich, the only two people who have competing products in this space are me and Dean Goedde. Are you accusing one of us of doing this? If so, come out and say it (and provide evidence). Otherwise, retract your insinuation. It's beneath you.

[rich smith]

Actually wasn't refering to you or Dean who I doubt resort to such tactics. Rather a general comment about those whose enthusiasm sometimes outstrips reality. If I had a problem of this nature with anyone specific I'd make my points directly but offline.

I was under the impression that, unlike Dean, yours was not so much a product as generous non-profit contribution. My mistake. Even so I can't imagine you as competitors. Like apples and oranges to me. Maybe Fient Kiss, RCAP, PZ, etc but not Attopilot.

Rich, the only two people who have competing products in this space are me and Dean Goedde. Are you accusing one of us of doing this? If so, come out and say it (and provide evidence). Otherwise, retract your insinuation. It's beneath you.

[zlite]

I was under the impression that, unlike Dean, yours was not so much a product as generous non-profit contibution. My mistake.

I'll ignore the sarcasm and clear up a point. ArduPilot is indeed a product, but it was created by a non-profit organization (DIY Drones) and sold at manufacturing cost as a contribution to the community. The software and all other intellectual property is donated to the community free of charge.

As you know, open source products can compete with commercial closed source products in the marketplace (think Linux and Windows). That doesn't make the open source not a product, it just means that it wasn't created for commercial purposes.

[spitfiremk9]

[QUOTE=rich smith]Actually wasn't refering to you or Dean who I doubt resort to such tactics. Rather a general comment about those whose enthusiasm sometimes outstrips reality.

Like yours then! you seem to have been most vioceiferous and enthusiastic here, as if you had some interest with U-nav? The reality is, dont treat your customers like something you've stepped in, they GRIPE.

[rich smith]

Chris you need to lighten up a bit and stop seeing sarcasm where there is none. Not having checked in recently I actually thought you might have gone commercial, maybe Ardupilot2, based on your own description as your "product".

IMO your AVR based board is best bet for DIY autopilot and intend to give it another try soon. I hope many bugs have been ironed out and expect to get one working some day.

I'll ignore the sarcasm and clear up a point. ArduPilot is indeed a product, but it was created by a non-profit organization (DIY Drones) and sold at manufacturing cost as a contribution to the community. The software and all other intellectual property is donated to the community free of charge.

As you know, open source products can compete with commercial closed source products in the marketplace (think Linux and Windows). That doesn't make the open source not a product, it just means that it wasn't created for commercial purposes.

[zlite]

Chris you need to lighten up a bit and stop seeing sarcasm where there is none. Not having checked in recently I actually thought you might have gone commercial, maybe Ardupilot2, based on your own description as your "product".

My apologies. I got all het up on the sock puppetry thing, and overreacted--sorry. I look forward to working with you on our continuing product development, and I'll try to stay out of toxic threads!

[tekrunner]

[QUOTE=rich smith]Actually wasn't refering to you or Dean who I doubt resort to such tactics. Rather a general comment about those whose enthusiasm sometimes outstrips reality.

Like yours then! you seem to have been most vioceiferous and enthusiastic here, as if you had some interest with U-nav? The reality is, dont treat your customers like something you've stepped in, they GRIPE.


Says it all right there. The reason comments regarding UNAV are so slanted is because they're really that bad.
In UNAVs defense Dave demonstrated his autopilots for me. However while doing this he literally made fun of the difficulties customers have had and declared the hobby community more trouble then they were worth. Any questions I had were met with insults.
Even people who have had good experiences with UNAVs products won't ever deal with the company again because of how they treat their customers.

[rich smith]

Although don't own one myself I did help a client get one going and it was the only one of 3 autopilots we tried that actually worked w/o additional assistance. Having no contact with the vendor may have worked to our advantage in this case.

I personally have more experience with DIY types but got so frustrated with bugs in firmware and docs that ended developing my own.

IMO those who make a big deal out of cosmetic issues that have no effect on performance should not be taken seriously.

[QUOTE=spitfiremk9]
Says it all right there. The reason comments regarding UNAV are so slanted is because they're really that bad.
In UNAVs defense Dave demonstrated his autopilots for me. However while doing this he literally made fun of the difficulties customers have had and declared the hobby community more trouble then they were worth. Any questions I had were met with insults.
Even people who have had good experiences with UNAVs products won't ever deal with the company again because of how they treat their customers.

[tekrunner]

IMO those who make a big deal out of cosmetic issues that have no effect on performance should not be taken seriously.
[QUOTE=tekrunner]

Agreed, cosmetics are of no concern to me either.

[ehx]

Overcast has MAJOR effect on dilution figures of GPS. Some units stop working completely when a cloud passes. Pretty obvious who's experienced in this stuff and who's not.


Are you really that ignorant? Think the military would design a world-wide navigation system that has trouble when it's cloudy or raining? I can hear it now. "Oh, no! There's a cloud! Call off the invasion! No mission today, I feel rain drops."

UNAV should be embarrassed to have such nonsense about GPS on their FAQ page.

[rich smith]

Are you really that ignorant? Think the military would design a world-wide navigation system that has trouble when it's cloudy or raining? I can hear it now. "Oh, no! There's a cloud! Call off the invasion! No mission today, I feel rain drops."
UNAV should be embarrassed to have such nonsense about GPS on their FAQ page.

I've written and modified GPS reciever firmware and spent several hundred hours testing them. Have you? And anyone who has tried to use a TomTom on the floor of the car when raining also knows what I'm talking about.

RCG should be embarassed to allow such ignorance on their site. But then again, if they didn't we would be left with only TV for entertainment. :eek:

[mlbco]

Information lifted from:

http://gpsinformation.net/gpsclouds.htm

1) Does RAIN or SNOW or CLOUDS affect the reception of my GPS receiver?
Answer: No. Not so as the user can tell without instrumentation.

2) I notice that when it rains and I turn on my windshield wipers my GPS has trouble locking. Doesn't this mean that rain affects my GPS reception?
Answer: No. What is affecting your GPS signal reception is the fact that the wipers running back and forth across your windshield is intermittently blocking reception and making it difficult for your GPS to get a complete navigation data string. Turning off your wipers until the signal locks will speed the initial lock.

3) Sometimes my GPS gets a thick coating of water on it and it does not receive as well. Does this not prove that rain can cause signal degradation?
Answer: No. A coating of water, even a fairly thin one is NOT the same as raindrops. The GPS signal frequency of about 1575mhz was chosen expressly because it is a "window" in the weather as far as signal propagation is concerned.

4) This all sounds good, but do you have a reference that supports these statements?
Answer: Yes.
See: Ref: http://www.navcen.uscg.gov/pubs/gps/sigspec/default.htm (Courtesy of Sam Wormley)

Cloud, Rain, Snow, weather in general does NOT attenuate the GPS signals enough to effect accuracy. As can be seen below, the total atmospheric loss (from all causes including rain, clouds, snow, fog, etc.) is but 2db. This is small compared with other variables.
L1 and L2 Navigation satellite Signal Power Budget

Parameter L1 P-Code L1 C/A-Code L2 P-Code
-----------------------------------------------------------------------------------------------------
User minimum received power -163.0 dBw -160.0 dBw -166.0 dBw
Users linear antenna gain 3.0 dB 3.0 dB 3.0 dB
Free-space propagation loss 184.4 dB 184.4 dB 182.3 dB
Total atmospheric loss 2.0 dB 2.0 dB 2.0 dB
Polarization mismatch loss 3.4 dB 3.4 dB 4.4 dB
Required satellite EIRP +23.8 dBw +26.8 dBw +19.7 dBw
Satellite Antenna gain at 14.3° 13.5 dB 13.4 dB 11.5 dB
worst case Block II off-axis angle
Required minimum satellite antenna +10.3 dBw +13.4 dBw +8.2 dBw
Input power 10.72W 21.88W 6.61W

5) Ok then, can I use my GPS underwater?
Answer: No. Just a few millimeters of "solid" water will severely attenuate the GPS signal.

Joe Mehaffey

[ehx]

I've written and modified GPS reciever firmware and spent several hundred hours testing them. Have you? And anyone who has tried to use a TomTom on the floor of the car when raining also knows what I'm talking about.


Using a GPS on the floor of a car when it's raining is your testing methodology? That's downright scary.

Hey, I suggest you contact the Coast Guard and tell them to fix their website. For some reason they seem to think GPS is an all-weather system. Explain your vast technical expertise to them and I'm sure they'll fix their FAQ right away.
http://www.navcen.uscg.gov/GPS/GPSfaq.htm

Anybody with any real GPS experience knows rich smith is dead wrong. He may really be that ignorant, but I think it's just trolling now.

If you are new to GPS and/or don't have a good understanding of how it works the Coast Guard site is a good starting point. There are plenty of links from there for more details. In particular check the reference information for a little more in-depth info.

[clolson]

Using a GPS on the floor of a car when it's raining is your testing methodology? That's downright scary.

Hey, I suggest you contact the Coast Guard and tell them to fix their website. For some reason they seem to think GPS is an all-weather system. Explain your vast technical expertise to them and I'm sure they'll fix their FAQ right away.
http://www.navcen.uscg.gov/GPS/GPSfaq.htm

Anybody with any real GPS experience knows rich smith is dead wrong. He may really be that ignorant, but I think it's just trolling now.

If you are new to GPS and/or don't have a good understanding of how it works the Coast Guard site is a good starting point. There are plenty of links from there for more details. In particular check the reference information for a little more in-depth info.

Is there anything on that site that discusses the potential adverse effects of weather on gps reception. I did a quick scan but didn't see anything. Maybe you could post a more specific URL that debunks this myth (assuming you are right that it is entirely a myth.)

That said, if I had a nickle for every time I heard "X shouldn't have any affect on reception / transmission at all" when in fact it does end up having a significant effect, I would be on the beach right now taking a break from being on the beach, instead of on my computer taking a break from being on my computer. :-)

Regards,

Curt.

[clolson]

I had a few minutes to do some googling. Most references seemed to agree that clouds and rain do not affect GPS *accuracy*. The following link suggests that clouds and rain could increase the time required to acquire an initial fix. (And it's makagps.com so it must be true) :-) Another site suggested turning off your wind shield wipers to see if that helps your gps get a fix.

http://www.makagps.com/faq/index.html#8

Looks like the consensus (based on a google search) is that clouds and rain shouldn't have any affect, at least not theoretically.

I'm not a gps expert ... but here's a question. Let's say (just about) everyone agrees that heavy rain does not slow the gps signals so timing and accuracy remains good. Could heavy rain still weaken the signal making it more difficult to acquire an initial fix?

[tekrunner]

I've written and modified GPS reciever firmware and spent several hundred hours testing them. Have you? And anyone who has tried to use a TomTom on the floor of the car when raining also knows what I'm talking about.

RCG should be embarassed to allow such ignorance on their site. But then again, if they didn't we would be left with only TV for entertainment. :eek:


I suppose next you'll site your economics degree to justify another trillion dollars in bankster bailouts for the economic recovery of America. Ofcoarse anyone not equipped with hundreds of hours on the floor of their car is not qualified to comment on the reception of their GPS receiver.

I think UNAV has a position open for you.

[patrickegan]

I was starting to think that with all of the apologies flying around it was more than likely just a big misunderstanding! Charity starts at home… :)

[tekrunner]

Pat, who's that in your avatar? I think it's a bit before my time but I recall seeing it at another forum so I'm curious. Care to enlighten a young soul?

[ehx]

It's not that water vapor in the troposphere (rain/clouds) has absolutely no impact on GPS performance. It's just that
it doesn't come close to mattering for meter-level positioning. GPS uses basic atmospheric models for
compensation and the position degradation in accuracy caused by the troposphere is typically well under a meter.
The reduction in signal to noise ratio, maybe a dB or two, is not significant.

You can be out in a torrential rain and it really won't matter. Accuracy wise or time to the initial fix. You just have
to make sure water can't puddle over the antenna.

You don't have to take my word for it. Try it yourself. Just make sure you do it in a good receiving area without
many obstructions so you're not polluting the data with varying satellite availability.

[patrickegan]

Why it is Dr. Strangelove. If you haven't see it you may want to look into it as it may help you relax. :)

http://www.imdb.com/title/tt0057012/

[spitfiremk9]

Why it is Dr. Strangelove. If you haven't see it you may want to look into it as it may help you relax. :)

http://www.imdb.com/title/tt0057012/

Darn, I thought that was you! Your so dissappointing.

[patrickegan]

Yeah, I know. You’re not the first person to be disappointed about me not resembling Peter Sellers…

[rich smith]

You are all wrong and that pleases me to no end. Probably wouldn't recognize an HDOP value if one bit you on the butt. :eek:

For the benefit of the silent majority I'll mention that half of the few dozen Trimble 502 (SVeeSix-CM3) purchased a few years ago from BG Micro do not lock in at all on a cloudy day and will lose lock if clouds pass. Some older Sony and Rockwell receivers lose lock in the rain and don't regain until it clears. In fact many of the 5 channel units and even a few more modern designs with chip instead of patch antennas behave like this. Newer SIRFIII and Fujitsu based GPS rarely fail under these conditions which probably gave rise to the misconception that precip has no effect.

I don't generally find it necessary to "site" my doctorate. In any case you might find a degree in engineering more useful. Or even a high school diploma. And of "coarse" I never mentioned spending hundreds of hours on the floor of my car however I can read and spell.

PS Personally I'm against any bailouts, "bankster" or otherwise. Would suit me fine if those who don't want to pay for what they buy fall flat on their face. GM etc too.

I suppose next you'll site your economics degree to justify another trillion dollars in bankster bailouts for the economic recovery of America. Ofcoarse anyone not equipped with hundreds of hours on the floor of their car is not qualified to comment on the reception of their GPS receiver.

I think UNAV has a position open for you.

[dmgoedde]

You are all wrong and that pleases me to no end. Probably wouldn't recognize an HDOP value if one bit you on the butt. :eek:
Speaking of HDOP (Horizontal Dilution of Precision) many people don't seem to know that besides weather, the current satellite positions have a profound effect on DOP. Trimble has some nice free utilities that tell you the various DOPs based on your location and time/date given a current ephemeris file. In general, when the satellites are spread out the position solution is stronger due to the greater angular seperation.

http://www.trimble.com/planningsoftware_ts.asp?Nav=Collection-8423

BTW - my doctorate is in chemistry and has nothing to do with this UAV/Autopilot nonsense.

[spitfiremk9]

You are all wrong and that pleases me to no end. Probably wouldn't recognize an HDOP value if one bit you on the butt. :eek:



I don't generally find it necessary to "site" my doctorate. In any case you might find a degree in engineering more useful. Or even a high school diploma. And of "coarse" I never mentioned spending hundreds of hours on the floor of my car however I can read and spell.

PS Personally I'm against any bailouts, "bankster" or otherwise. Would suit me fine if those who don't want to pay for what they buy fall flat on their face. GM etc too.

Come on now Rich, your getting all feminine and bitchy, however, if you are a teenage female, logging in under a different name like some apparently do, please accept my apologies.

[patrickegan]

Come on now Rich, your getting all feminine and bitchy, however, if you are a teenage female, logging in under a different name like some apparently do, please accept my apologies.

We'll have to make sure that post makes it in the sitcky :rolleyes: :)

[Gary Mortimer]

Could somebody explain Janky please.

[carguy84]

Come on now Rich, your getting all feminine and bitchy, however, if you are a teenage female, logging in under a different name like some apparently do, please accept my apologies.
http://www.nvnews.net/vbulletin/images/smilies/popcorn.gif

[carguy84]

Could somebody explain Janky please.
http://www.urbandictionary.com/define.php?term=Janky

[Cort]

well spoken dmgoedde! seems like everyone is forgetting that....personally I don't know about the clouds....I survey to within centimeter accuracy all the time (RTK) when its cloudy and raining....and its certainly possible to post process your position to that accuracy under all kinds of conditions assuming you know what you are doing.

Cheers,

Cort

[eddymoore]

Interestingly, surveying-grade GPS units to use temp/baro sensors to improve the accuracy. They do affect position fix, but only when you're after mm/cm-scale accuracy.

Disclaimer (as seems fashionable): I don't have a doctorate in GPS. But this information comes from someone who is half way through one.

[patrickegan]

Did you stay at a Holiday Inn? :)



janky
adjective used to describe a person, place or thing which is questionable, f-ed up, wrong, strange, broken down, undesirable, and/or just some thing you can't think of another word for.

[rich smith]

Come on now Rich, your getting all feminine and bitchy, however, if you are a teenage female, logging in under a different name like some apparently do, please accept my apologies.


No No... It's me that needs to apologize. That time of the month you know.

[kbosak]

No Pat, log on to their website diydrones.com and look for yourself (its free!!) You'l see, those rascals down at U-nav realy had ground off the chip ID's and the boards turned out to be real cheap hobby things aparently, no wonder they were having so many complaints!
Could you enlighten me as to what "petting pooches and stirring poop" has to do with pointing out pertenant facts?
If you look at your PC or cellphone, the components usually costs somewhere between 10-20%. The rest are software engineers and marketing. Component research is costly and grinding prevents reverse engineering. A single info about voltage reg used saves a few days of trials under the name 'is the noise suppresion enough for a typical cheap RC equipment'.

[kbosak]

Well, with UNAV you wonder just how well these guys know their stuff. On their FAQ page, for example, they claim that clouds and rain reduce GPS performance. In reality, the GPS frequencies were chosen precisely because they are NOT affected by weather.
Or maybe they just don't want their autopilots to be flown by unskilled amateurs in zero-visibility conditions when their UAV could harm the real planes?

[Gary Mortimer]

top answer

[patrickegan]

Or maybe they just don't want their autopilots to be flown by unskilled amateurs in zero-visibility conditions when their UAV could harm the real planes?

That would make sense as they (U-nav), have a vested interest in this remaining legal. :)

[tekrunner]

That would make sense as they (U-nav), have a vested interest in this remaining legal. :)



Outlaw autopilots and only outlaws will have them :)

I can just imagine "Lord of war 2" with Nicholas Cage "Arms embargos are impossible to enforce. And I routinely mislabeled 3500FW as Ipod repair parts"

[zlite]

[deleted]

[patrickegan]

Many people (across the board) are in denial about the reg’s and should be told a lot of things before they purchase and or use any of these appliances. If you are flying VLOS that means you are flying under VFR (Visual Flight Rules) VFR assumes weather minimums, cloud separations etc. It is issues like these that make the FAA want regulation.

[EddieHaskell]

Many people (across the board) are in denial about the reg’s and should be told a lot of things before they purchase and or use any of these .... It is issues like these that make the FAA want regulation.

Yes, especially these so-called open source products.
While promoting dirt cheap hardware what they don't tell their customers is that it will probably cost them a dozen airframes to debug their firmware. The consiqences of a hardware or software error in an autopilot can be pretty harsh, usually ending in a crash or a fly-away.

The problem with open-source software is its often full of bugs, either unintentional or intentional. You can imagine what an opportunity an open-source autopilot project would be for a hacker. The thought of causing planes to spiral into the ground or fly-away would be almost irresistable. It's happened before on other open source autopilot projects.

And the thought of autonomous planes flying around with amatuer built autopilots inside is reason enough for the FAA to clamp down hard on sUAS operations. Frankly, these open-source, DIY products couldn't have appeared at a worse time for the UAS community, they play right into the hands of the anti-sUAS crowd. It looks to me like we will soon be seeing FAA regulations that prohibit auto-nav capability with any uncertified, unmanned airplane, similar to the current AMA rules. Then, the only lawful autonomous operations will be with a $50K certified UAS.

[clolson]

The problem with open-source software is its often full of bugs, either unintentional or intentional. You can imagine what an opportunity an open-source autopilot project would be for a hacker. The thought of causing planes to spiral into the ground or fly-away would be almost irresistable. It's happened before on other open source autopilot projects.

Wow! I don't mean to disagree, but you are flat out wrong, misguided, or intentionally spreading mis-truth ... everything in this entire paragraph is the polar opposite of the truth.

You say "open-source software is full of bugs": it's possible sure, but commercial software also can be equally full of bugs. They are often better hidden (and harder to work around) with commercial software. There is nothing inherent with open-source software that has anything to do with bugginess. Typically the maturity of software is a much better indicator of bugginess.

You say "... full of bugs, either unintentional or intentional": Did you mean to imply that open-source software is often *intentionally* full of bugs? I don't even need to respond to this, I only need to shine a flashlight on it and make sure it doesn't slip through unnoticed and stick to someone else's subconscious.

You suggest evil hackers would attempt to damage open-source code? How??? Open-source code is *highly* peer reviewed -- something that commercial code cannot take advantage of. Permission to make changes to the code is almost always strictly controlled. I would suspect commercial code (because it is closed and hidden and I can't see inside) of having a bigger chance of viruses, bugs, or being attacked by evil hackers compared to open-source which has the lights on, the windows open, light flowing in, anyone can look inside and shine the microscope. There is a lot of commercial code that would hate being exposed to public review because the things that people would see would be very embarrassing.

You say: "This has happened before on other open-source autopilot projects". Wow, really? Which ones? I pretty much live under a rock most days so I haven't heard of any situation like this. I'd love to hear the stories. Any links?

I am climbing into my fireproof asbestos suit right now, so bring it on!!!! :-)

Curt.

[Gary Mortimer]

I am climbing into my fireproof asbestos suit right now, so bring it on!!!! :-)

Well it is a holiday weekend and each to their own

[zlite]

Eddie's post was either meant as a troll or is so misinformed that you have to wonder if he's ever actually seen an open source project.

Yes, especially these so-called open source products.
"so-called"? What does that mean? Are you confused about the definition of open source? Or are you suggesting that projects like Paparazzi or ArduPilot don't qualify? If, so please explain why you think that.

While promoting dirt cheap hardware what they don't tell their customers is that it will probably cost them a dozen airframes to debug their firmware. The consiqences of a hardware or software error in an autopilot can be pretty harsh, usually ending in a crash or a fly-away.

Again, that's simply inflamatory. As far as we know, not a single airframe has been lost in ArduPilot development. We have a built-in hardware failsafe specifically to ensure that buggy code will not stop a pilot from regaining control. Paparazzi has been used by dozens of university teams at this point and is as mature as many commercial autopilots.

The problem with open-source software is its often full of bugs, either unintentional or intentional. You can imagine what an opportunity an open-source autopilot project would be for a hacker. The thought of causing planes to spiral into the ground or fly-away would be almost irresistable. It's happened before on other open source autopilot projects.
I'm going to call BS on that. Provide evidence of such intentional abuse or retract your statement.

[dmgoedde]

Come on - we all know EddieHaskell and ChuckyDGr8 are NOT real independent people on here - They are a spoof (2nd Avatar of another person) asking just the perfect questions to help along certain discussions. I call a HUGE BS on that.

This is what only children do when they have no friends - they make up imaginary friends. It is sad! :(

[rich smith]

I must agree with Clolson in that commercial software is almost as likely to have bugs. And what you pay don't always indicate reliablilty. I helped with three and we had more success with the one that cost few hundred than the ones that cost thousands.

IMO losing planes has more to do with failsafe and recovery procedures though. Even buggy firmware is no excuse for fly aways and crashes. Key is to allow switch back to manual as top priority. Chris uses separate chip for his project and I rely on AVR WDT for my design both of which are pretty dependable solutions. The right type of RX is important too.

No matter what there is still chance of fly-away so a good tracking system is important too. We stopped losing planes after implementing the setup in my GPS/XBee tracking thread. 50 bucks and paid for itself first day.

I do agree however that some open source packages are intentionally sabotaged. Usually to protect a related commercial product or in anticipation of such. I know of at least a couple clear cut examples of bugs being purposely inserted to bypass GNU restrictions and suspect hundreds more cases. Sometimes it's an uphill battle to reconstruct binary that matches published files and not always due to tools issues.

In fact it is rare to actually get binary to compare but usually caused by carelessness and incompetent document control.

Yes, especially these so-called open source products.
While promoting dirt cheap hardware what they don't tell their customers is that it will probably cost them a dozen airframes to debug their firmware. The consiqences of a hardware or software error in an autopilot can be pretty harsh, usually ending in a crash or a fly-away.

The problem with open-source software is its often full of bugs, either unintentional or intentional. You can imagine what an opportunity an open-source autopilot project would be for a hacker. The thought of causing planes to spiral into the ground or fly-away would be almost irresistable. It's happened before on other open source autopilot projects.

And the thought of autonomous planes flying around with amatuer built autopilots inside is reason enough for the FAA to clamp down hard on sUAS operations. Frankly, these open-source, DIY products couldn't have appeared at a worse time for the UAS community, they play right into the hands of the anti-sUAS crowd. It looks to me like we will soon be seeing FAA regulations that prohibit auto-nav capability with any uncertified, unmanned airplane, similar to the current AMA rules. Then, the only lawful autonomous operations will be with a $50K certified UAS.

[spitfiremk9]

Wow! I don't mean to disagree, but you are flat out wrong, misguided, or intentionally spreading mis-truth ... everything in this entire paragraph is the polar opposite of the truth.

You say "open-source software is full of bugs": it's possible sure, but commercial software also can be equally full of bugs. They are often better hidden (and harder to work around) with commercial software. There is nothing inherent with open-source software that has anything to do with bugginess. Typically the maturity of software is a much better indicator of bugginess.

You say "... full of bugs, either unintentional or intentional": Did you mean to imply that open-source software is often *intentionally* full of bugs? I don't even need to respond to this, I only need to shine a flashlight on it and make sure it doesn't slip through unnoticed and stick to someone else's subconscious.

You suggest evil hackers would attempt to damage open-source code? How??? Open-source code is *highly* peer reviewed -- something that commercial code cannot take advantage of. Permission to make changes to the code is almost always strictly controlled. I would suspect commercial code (because it is closed and hidden and I can't see inside) of having a bigger chance of viruses, bugs, or being attacked by evil hackers compared to open-source which has the lights on, the windows open, light flowing in, anyone can look inside and shine the microscope. There is a lot of commercial code that would hate being exposed to public review because the things that people would see would be very embarrassing.

You say: "This has happened before on other open-source autopilot projects". Wow, really? Which ones? I pretty much live under a rock most days so I haven't heard of any situation like this. I'd love to hear the stories. Any links?

I am climbing into my fireproof asbestos suit right now, so bring it on!!!! :-)

Curt.

Very well put Curt, my sentiments entirely

[spitfiremk9]

Yes, especially these so-called open source products.
While promoting dirt cheap hardware what they don't tell their customers is that it will probably cost them a dozen airframes to debug their firmware. The consiqences of a hardware or software error in an autopilot can be pretty harsh, usually ending in a crash or a fly-away.

The problem with open-source software is its often full of bugs, either unintentional or intentional. You can imagine what an opportunity an open-source autopilot project would be for a hacker. The thought of causing planes to spiral into the ground or fly-away would be almost irresistable. It's happened before on other open source autopilot projects.

And the thought of autonomous planes flying around with amatuer built autopilots inside is reason enough for the FAA to clamp down hard on sUAS operations. Frankly, these open-source, DIY products couldn't have appeared at a worse time for the UAS community, they play right into the hands of the anti-sUAS crowd. It looks to me like we will soon be seeing FAA regulations that prohibit auto-nav capability with any uncertified, unmanned airplane, similar to the current AMA rules. Then, the only lawful autonomous operations will be with a $50K certified UAS.

Ballcocks

[Gary Mortimer]

are generally orange and way more important than any uav

[dmgoedde]

How about this: back to topic. Stripdown.

Gyro: One of the ADXRS, you can tell via metal top.
Processor: some 8-bit PIC

Here's an idea for the good folks at DIY Drones:
1) Open-source turn rate wing level autopilot to mirror the FMA-based ArduPilot
2) Upgrade from 8 bit PIC to the Arduino processor platform
3) Use the inexpensive LISYAL300 yaw gyro instead of the expensive ADXRS used int he Pico-N (LISYAL300 is $10 in low Qty vs $50 for the ADXRS)
4) Use the EM-406 GPS already in use by ArduPilot.

My estimate is PCB + Arduino + LISYAL300 + Vreg and what not puts the cost real close to the $25 price of the current Arduino Pilot. Overall system cost would be cheaper because the FMA sensors are the most costly part of the Arduino system. You already got ADC inputs on the Arduino, so have Tom Pycke on DIY Drones help out with the super simple code to filter together and bias correct yaw gyro with the 1Hz GPS, and throw in the nav code you already have in the Arduino Pilot. I am POSITIVE the performance bar could be raised on turn rate wing levellers, and FIRMLY put this simple technology where it belongs: as a low cost learning project, not a $500 system.

[zlite]

How about this: back to topic. Stripdown.

Gyro: One of the ADXRS, you can tell via metal top.
Processor: some 8-bit PIC

Here's an idea for the good folks at DIY Drones:
1) Open-source turn rate wing level autopilot to mirror the FMA-based ArduPilot
2) Upgrade from 8 bit PIC to the Arduino processor platform
3) Use the inexpensive LISYAL300 yaw gyro instead of the expensive ADXRS used int he Pico-N (LISYAL300 is $10 in low Qty vs $50 for the ADXRS)
4) Use the EM-406 GPS already in use by ArduPilot.

My estimate is PCB + Arduino + LISYAL300 + Vreg and what not puts the cost real close to the $25 price of the current Arduino Pilot. Overall system cost would be cheaper because the FMA sensors are the most costly part of the Arduino system. You already got ADC inputs on the Arduino, so have Tom Pycke on DIY Drones help out with the super simple code to filter together and bias correct yaw gyro with the 1Hz GPS, and throw in the nav code you already have in the Arduino Pilot. I am POSITIVE the performance bar could be raised on turn rate wing levellers, and FIRMLY put this simple technology where it belongs: as a low cost learning project, not a $500 system.

That's a great idea. We'll do it.

I'll bet we can have it out for $49 (or $99 with GPS) by the end of summer, and it will outperform the PicoPilot in every dimension (including the groundstation/waypoint setting software). Cutting the price of commercial autopilots by a factor of five is what we do best!

[dmgoedde]

I already did it myself, but have not spent enough time to fully round it out. Nonetheless, I have about 10 hours of flights on this system in my Miss2. To boot, it has things like 400 waypoints, 3D waypoints, integrated data logging to SD and 2-way com.

The LISYAL300 bias seems to 'walk' more than IDG300 and maybe ADXRS units, but worked well enough. Besides, the GPS is there to track bias drift in the code.

However, after being fully saturated flying the 3 axis AttoPilot, all I can say is a big YUCK using motor gliders and relying on a good elevator trim positions and keeping turns slow and wide to prevent tip stall. Also, it really SUCKS relying on throttle to control altitude. This first hand experience means that I dropped the entire project myself.

Have at it - I am NOT going to touch this one! Not to discourage, because I know it works well in a VERY limited situation... but I am simply used to being able to install my autopilot on anything from an 8 oz plank to a 30 Lb military wing UAV or an 8' telemaster without worry about goofy altitude control via throttle, or being stuck with motor gliders.

BTW - the defense for motor gliders that I have heard (that the "Raven" is what the military wants anyway) is going to be BOGUS rather soon.

[patrickegan]

They have new stuff in the pipeline. Raven is/was good but... I've seen hobby stuff the rivals it for much less. Anyone think it may have to do with vendors wanting autopilot certification??? :rolleyes:

[dmgoedde]

I've never seen the Raven first hand, but SF guys that have told me the electric motor is loud, the plane is slow, and cameras are fixed position.

[dmgoedde]

They have new stuff in the pipeline. Raven is/was good but... I've seen hobby stuff the rivals it for much less. Anyone think it may have to do with vendors wanting autopilot certification??? :rolleyes:I think it has to do with big companies getting comfortable while being stubborn.

[patrickegan]

I've never seen the Raven first hand, but SF guys that have told me the electric motor is loud, the plane is slow, and cameras are fixed position.

And that was what they were shooting for... I had lunch with Dr. MacCready a few years ago and I'll say most of us fly (or have flown) the same gear. I don't have any up close photos as it could be an "ITAR" issue. :eek:

[kbosak]

Eddie's post was either meant as a troll or is so misinformed that you have to wonder if he's ever actually seen an open source project.

"so-called"? What does that mean? Are you confused about the definition of ope
Maybe because of the total lack of regression tests in the code?

AFAIK the definition of open source is that if you criticise open source software, you can identify the expert users that would never appreciate your commercial product :D This helps a lot in business planning.

[kbosak]

...

[patrickegan]

Originally Posted by zlite
Eddie's post was either meant as a troll or is so misinformed that you have to wonder if he's ever actually seen an open source project.

"so-called"? What does that mean? Are you confused about the definition of ope

kbosak Maybe because of the total lack of regression tests in the code?

AFAIK the definition of open source is that if you criticise open source software, you can identify the expert users that would never appreciate your commercial product This helps a lot in business planning.

Would this still apply to those giving it away? (not for profit)

[clolson]

AFAIK the definition of open source is that if you criticise open source software, you can identify the expert users that would never appreciate your commercial product :D This helps a lot in business planning.

Criticism is generally a good thing and should be welcomed (even if it can be painful) but whenever criticism is levied unfairly (as is often the case) then certainly you will hear voices defending themselves. Criticism will definitely also pull out the people with thinner skin, even when it is fair criticism. :-)

Curt.

[zlite]

I already did it myself, but have not spent enough time to fully round it out. Nonetheless, I have about 10 hours of flights on this system in my Miss2. To boot, it has things like 400 waypoints, 3D waypoints, integrated data logging to SD and 2-way com.

The LISYAL300 bias seems to 'walk' more than IDG300 and maybe ADXRS units, but worked well enough. Besides, the GPS is there to track bias drift in the code.


I talked this over with Jordi, and he explained why this would be a mess to do. We're using a 5V board (which is the Arduino standard). The 5v gyros, such as the ADXRS series, aren't temperature compensated and are a hassle to work with. Meanwhile the LISY300AL is a 3.3v gyro, and we'd risk losing resolution on a 5v board.

Plus, he agrees with you: at the end you just get a mediocre autopilot that doesn't handle slow fliers well. Better to go all the way to a full IMU.

[small_rcer]

I think Dean may have been pointing out that TRL as used in other unnamed products is really only suitable for slow high wing glider types. Dean fully grasps the difference in costs and performance. He is able to recognize which technology gives value and quality of performance in high performance platforms.

So don't go down the route of the UNamed company. I feel Dean knows very well, as apparently you do, that is not a viable solution.

Jim H

[dmgoedde]

I talked this over with Jordi, and he explained why this would be a mess to do. We're using a 5V board (which is the Arduino standard). The 5v gyros, such as the ADXRS series, aren't temperature compensated and are a hassle to work with. Meanwhile the LISY300AL is a 3.3v gyro, and we'd risk losing resolution on a 5v board.

Plus, he agrees with you: at the end you just get a mediocre autopilot that doesn't handle slow fliers well. Better to go all the way to a full IMU.Chris - temperature compensations and drift are not special problems, they are inevitable! All you do is compensate for them with GPS heading info in a math filter. I got code to do it, and my turn rate wing level autopilot worked quite well in the Miss2 once I hammered out the proper P and D response ratios. You aren't going to lose too much resolution using the 3V LISYAL300 with a 5V ADC. I am not saying this is a great autopilot solution, but it DOES work as we all know Maynard Hill's trans-Atlantic crossing used a turn rate wing leveller and that plane was not even a motor glider.

One marginality is that a single yaw gyro doesn't directly give yaw rate info unless the UAV attitude is perfectly flat. Real planes bank in turns, and to fully track aircraft-centric yaw change relative to Earth you must have full 6 DOF IMU and the full matrix of partial differentials that convert 3-D rotations between the two reference frames and take into account things like centripetal forces, so now you need forward speed as well.

If you take a dynamically stable system like a motor glider, then a single yaw gyro can keep on top of it and the super simple "IMU" won't diverge because it is just too simple to be unstable. Relying on a motor glider is KEY.

My point: I would estimate the UNammed autopilot company won't sit on their laurels forever... I would expect an inexpensive IMU autopilot, or maybe a newer $500 unit that also has pitch rate sensor for a more complete flight solution. Why let them keep selling a turn rate wing level autopilot for $500 when the technology is on the DIY or hobby level? I say democratize it with a $100 total price Arduino-TRWL including the GPS module. LISYAL300 is only $10. (TRWL = Turn Rate Wing Leveller).

[kbosak]

Why let them keep selling a turn rate wing level autopilot for $500 when the technology is on the DIY or hobby level?
Precisely because the software development technology I observe at DIY level is extremely far from what I have observed and used in embedded software development. DIY segment has a completely different level of reliability, but is also much more fun to do. I would say they they are fantastic for discussion, but nobody seems to do serious regression testing, no datalogging on all units etc. Basically participants of the projects like ArduPilot don't know much about how it will behave during 1h flight. Will any counter roll over? Who cares. 'It works for Bob and Bill who are good friends and Tim's son is using same code, too.'

[zlite]

Precisely because the software development technology I observe at DIY level is extremely far from what I have observed and used in embedded software development. DIY segment has a completely different level of reliability, but is also much more fun to do. I would say they they are fantastic for discussion, but nobody seems to do serious regression testing, no datalogging on all units etc. Basically participants of the projects like ArduPilot don't know much about how it will behave during 1h flight. Will any counter roll over? Who cares. 'It works for Bob and Bill who are good friends and Tim's son is using same code, too.'
Good points--but give us time. ArduPilot is just nine months old, but we've managed to already release two commercial boards (ATmega168 and new ATmega328) and two major releases of the software, with a ground station and desktop setup utility out this week (winning an autonomous vehicle competition along the way).

We'll get to proper datalogging and stress testing over the next few months, along with releasing an expansion board with an airspeed sensor and throttle control and paving the way for the next, IMU-based, version of ArduPilot.

The nature of our open source project is that it moves fast and cheap but in perpetual beta. If that's your idea of fun (and it is for many people) ArduPilot is a great project to learn with and for hobbyists who want to modify or adapt an autopilot for their own purposes. We may not the best autopilot on the market, but we will be the cheapest, most open and fastest-evolving one.

But for those who want a robust, pro-quality autopilot that can be trusted for hour-long flights out of sight, we recommend AttoPilot, which has indeed been tested the way you suggest.

[reph]

LISY300AL is now $5.36 qty 1 at Arrow. If you do your own fab + asm you can actually build a low end 6DOF MEMS IMU for less than a $43 IR sensor ($68 if you concede you need Z axis IR too). And obviously IMUs don't have to be mounted externally, pointing to the horizon much of the time, with suitable weather and terrain. Also no patent royalties. Once the IMU control theory and SW matures some more, IR should disappear very quickly in hobbyist UAVs.

[spitfiremk9]

Just had the lid off my Cloud Cap Picollo today and guess what, all the ID numbers on the chips are still there!?

What those rascals at Unav will do to make their products ligher is amazing

[kbosak]

Just had the lid off my Cloud Cap Picollo today and guess what, all the ID numbers on the chips are still there!?

What those rascals at Unav will do to make their products ligher is amazing
Just visited their webside. The RS-232 connector of the size of the rest of the IMU is truly awesome. But circular military with plastic cap ona a leash would be better.
There is an explanation however:
With amateur users, they will be criticising more the unit with 4USD gyro than those with 23USD gyro. And nobody will spot that the most work is in unique software. Truly unique software, without a single bit shared with Linux or anything. The Coudap clients, apparently, know that the know-how is in the overall integration and results and they know how to judge and what to chose.
My bottom line is: if you use more drifting gyro and compensate it with 1 month of work on better Kalman implementation, it's your choice and you still deserve the money. Sometimes you have to grind the chips then, because of the horde of amateurs claiming their wiimote could fly as well what is annoying to straighten out.

[Gary Mortimer]

Cloudcap being bought by Goodrich and signing deals left right and centre with sensor suppliers. they are big players now.

I think Stikmonkeys entry in the OBC might be a tech demonstrator for them, if not, it should be.