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DIY autopilot


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Most of my parts are chinese cheapies. All have worked great so far and quality has been fantastic for the price. I've bought the key items from US suppliers (motor controller, compass module) as there was no good generic available that I could find. Almost everything else is from banggood.com. Free shipping on everything!

 

warning tho - bangood is highly addictive.

 

Another site along those lines is http://www.sainsmart.com.  Shipping isn't free but it is cheap; $5.00 USD to get my 9 inch touch screen shipped by China Post.  The screen was only $55 USD

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It's about time we had something to take on the costs of these things. An AP is simply not that expensive to make by the manufacturers. They charge what they do because they can, not due to cost of making. There is not a great deal inside the units and most of the "brains" is inside a Chip. There would be lucky to be maybe $80 worth of parts inside. As IT said, the compasses and Rate Gyro are all solid state now. The old compasses were a bit more expensive due to a lot more manual labor involved, but now the Solid state devices are few bucks if even that.

 

It's not until you start playing around with these things that you realise how much effort goes into the R&D, writing and maintaining the code etc.  I'm not saying they aren't making lots of profit on this stuff but their costs are definitely significantly more than just the sum of the parts.  Take a look at how many lines of code have gone into Slanty's project.  This is all possible because of everyone contributing their code for free under an open source license.

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This is a cool project. I've been considering going the other way. I want the expensive B&G autopilot computer, but i want the same cheap tiller pilot actuator. 

I think the b&g unit just has relay outputs , one for each direction of rudder. 

I've been considering wiring these up to a butchered tiller pilot with DIY rudder feedback like you've done

 

That way I get their fancy tech for control (can control AP from Chartplotter or wireless remote)  but with an affordable actuator (old tillerpilot)

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Sounds like a plan Winter - you'd just want to be satisfied that the B&G motor control is going to be compatible with your autopilot. IT might be in a better position to comment on that one.

Oh its not. Its going to involve some hackery driving relays etc to the hacked open tiller pilot

 

b&g want me to buy their spenny actuator 

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The B&G AP computers (AC12, AC42, NAC 2 and NAC3 ) will control pretty much any 12 or 24v steering system. They will auto sense a switching system or proportional voltage control. You definitely DONT need a B&G drive.

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It's not until you start playing around with these things that you realise how much effort goes into the R&D, writing and maintaining the code etc. I'm not saying they aren't making lots of profit on this stuff but their costs are definitely significantly more than just the sum of the parts. Take a look at how many lines of code have gone into Slanty's project. This is all possible because of everyone contributing their code for free under an open source license.

For sure Ferrari, come on Wheels. If slanty's nifty machine fails next week. He will say 'oh well', that component cost $X, I'll put a new one in / up-spec / learn from failure and improve, part of the fun. If your B&G fails after 3 years, your furious, plus they make heaps of them. They all fail, they start crashing / crash tacking or gybing boats, boats are damaged or people are hurt the manufacturer have big issues. Their kit is full of programming, slanty has the benefit of someone else's base script to use, its complex, but the system is reasonably basic, in that it has no NMEA in or out, no wind mode, no cross track error mode, no auto guidance like garmin have. Branded units are waterproof, rugged, reliable, thoroughly tested. The components are suitable for long distance off shore sailing. What Slanty has made is cool, and I have respect for what he has done, once it's all in boxes etc it will be good, but it still won't be the same as a branded unit. The components cost much more than $80, they are using quality screens, keypads, connectors, and all the other components, they put years into r&d, offer warranties and onboard support. When you can do that for $80, I'm sure everyone here will buy 2.

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The components cost much more than $80, they are using quality screens, keypads, connectors, and all the other components, they put years into r&d, offer warranties and onboard support. When you can do that for $80, I'm sure everyone here will buy 2.

You would be surprised, in fact shocked, at how cheap all that stuff is too a Manufacturer now. It is all really cheap. Also remember that none of this stuff is in a development stage. It's all been around for many many years and very little development is required. There is far more power in your base level Smart phone that one of these AP's and smart phones are cheap to make. Yes there is a big difference when it comes to the mass production, but still not in the level we end up paying. Laptops are even cheaper. Flatscreen TV's are made for peanuts. We are talking tens of dollars, not hundreds.

 Apple iPhone 6 plus (16GB) Production cost=$215.60  Sell price $749  profit margin 71.2%

Google Pixel XL (32GB)  $285.75  $769  62.84%

 

Samsung Galaxy S6 (32GB) $275.50  $699.99  60.6%

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Sorry wheels, I completely disagree re development. There is quite a bit of development going on with APs and instruments. The sailing algorithms  are under constant development and are getting better all the time. The heading sensors too. The ability of the top end units to compensate for boat/rig movement to have accurate wind data etc, the ability to compensate for everything (upwash, mast twist, rake, sail selection, wind and boatspeed, etc etc) are all new. Like everything at the top end of technology there is a constant race to be ahead of the competition.

Price.

10 years ago a top end pilot and instruments were over $100K (Like a vendee globe boat might use). Same level now, 30-40K. This is a huge drop in revenue for the marine electronics companies, so they have to sell more. They dont sell that many compared to most industries - there simply is not sufficient volume.

For example, according to Bavarias stats, their Farr designed 52 cruiser (? cant remember the exact model) sold about 100 units last year, which they say is 20% of the worldwide market in the 50-60 ft range....who are likely to use this stuff.

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 Apple iPhone 6 plus (16GB) Production cost=$215.60  Sell price $749  profit margin 71.2%

Google Pixel XL (32GB)  $285.75  $769  62.84%

 

Samsung Galaxy S6 (32GB) $275.50  $699.99  60.6%

 

That's not really a fair representation of profit Wheels, manufacturing is possibly the cheapest part of the equation. You need to add in the hardware R&D, the software R&D and the R&D on all the products that failed and didn't make it to market. There is significant financial investment and risk that goes into these things before they make a buck. 

 

If you phoned up Who Flung Dung it China and asked him to develop and manufacture a Samsung or Apple beating phone for $300 he'd spit out his fried rice with laughter.

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I'd like it as cheap as a fair day's work for a fair day's pay. Superprofits and luck and greed stink.

Kevin, how do you know what the costs involved with this are? Do you have any evidence at all to suggest Navico are makeing "superprofits"?

We don't know the RD, production or any other costs associated with this at all, just guessing. Personally, I think the price IS reasonable at its current level.

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Not accusing them. Making a general statement. In absence of transparency ....

I should have added "secrecy stinks". It's well known that we all get better results from open science.

You and wheels are in another planet. The leading marine electronics brands spend MILLIONS on R&D, as IT said. Why would they share the results of their hard work? Buying cheap components from china wouldn't be an option if china hadn't copied someone else's hard work, or the idea for the item in the first place. Do you think the knock off manufacturers pay a royalty back to the company that did the R&D?

Do you realise if someone hadnt put the R&D into making AP's in the first place, we wouldn't have them at all. Does that person not deserve a reward for their time, money and risk?

How much do you think the arduino system will cost all up? Electrical components, wiring, ram (remember Slanty is using an existing ram from a company that put in a heap of $ to making a good reliable ram), then add in the time for assembly, testing. You would be near 800 if you valued your time even at minimum wage, certainly once you consider the time it requires to write the software, and your left with a basic AP, of what reliability? If Slanty agreed to sell them to people, I'm sure it wouldn't be the cost of components + $50.

Still, no disrespect to Slanty, cool project, great if you have the spare time and skill.

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Good you fullas aren't disrespectin me.

 

Anyway, the important components in this build arent chinese knockoffs. They are brand components with the r&d done. Pololu still manage to build a tilt roll and pitch compensated compass for 20 bucks. This is generally used in drones and other rc stuff. I think the marine engineers are getting outflanked a bit on the innovation/pricepoint factor in recent times.

 

Instead of moaning about that i chose to exploit it. Sorry for the typos. On a phone.

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You and wheels are in another planet. The leading marine electronics brands spend MILLIONS on R&D, as IT said. Why would they share the results of their hard work? Buying cheap components from china wouldn't be an option if china hadn't copied someone else's hard work, or the idea for the item in the first place. Do you think the knock off manufacturers pay a royalty back to the company that did the R&D?

Do you realise if someone hadnt put the R&D into making AP's in the first place, we wouldn't have them at all. Does that person not deserve a reward for their time, money and risk?

How much do you think the arduino system will cost all up? Electrical components, wiring, ram (remember Slanty is using an existing ram from a company that put in a heap of $ to making a good reliable ram), then add in the time for assembly, testing. You would be near 800 if you valued your time even at minimum wage, certainly once you consider the time it requires to write the software, and your left with a basic AP, of what reliability? If Slanty agreed to sell them to people, I'm sure it wouldn't be the cost of components + $50.

Still, no disrespect to Slanty, cool project, great if you have the spare time and skill.

 

Yeah, and on top of R&D, parts costs for electronic devices, especially when they have moving mechanical components, all add up quite quickly even for high volume products. Marine electronics, especially high end stuff, is probably pretty low volume. Even things like fasteners, cables, assembly, packaging all add up more than you might think. Tooling up for manufacture is obviously another big front end cost that needs to be amortised. And the products sold need to fund all the management etc. that goes along with this. I doubt many big companies are doing anything more than providing a decent ROI for their shareholders -- otherwise someone would just undercut them.

 

I've also made an arduino-based tiller pilot.... using a 9-axis IMU with some fairly fancy proprietary sensor fusion algorithms on board (very cheap now as they're used on cell phones) which is incredibly accurate and responsive. Hard bit's always been the programming, I got it to the stage where it works quite well, but occasionally it'll all of a sudden lose the plot due to a bug somewhere. I've lost interest in it for now (it was always just for fun rather than a money saving exercise or anything) so using a secondhand ST1000. Nothing like as responsive, but it's reliable.

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