Arduino Nmea Mega Thread

Done some more work on the UI. The NMEA data is perfectly happy streaming out so thats a done deal and I wanted to have a go at the compass/heading/speed concept.

Realised that I need a combined magnemoter/accelerometer (more trial and error) but pressed on anyway to see if I could proof of concept it. Needs tidying and a fair bit more code but its promising.

I have mounted a temperature sensor on the breadboard ready to code into the environmental window, and the GPS data will go into the relevant place shortly.

All looks very good.

Are you looking at the MPU 9050 for the heading unit? To do tilt correction on the compass while under way I think you may need a unit with magnetometer, accelerometer & gyro [otherwise the lateral accelerations will be combined with tilt]. I think there are some libraries out there that can do some of that.

My interpretation of your display is that your heading is 260 [True, Magnetic or Compass?], and that the arrow indicates that I should be steering to Port to a heading of less than 260. Not sure about the meaning of CTS [course to steer] being 285 - or is that COG [course over ground]?
 
Not sure about the meaning of CTS [course to steer] being 285

I assume that's the desired heading, locked in manually by the navigator. The old Raymarine ST50 compass display had this function, except that it displays the difference visually, with a needle like a wind gauge. It makes it very easy to hand-steer a set course; you don't even need to remember what it was, just keep the needle upright. It also works when the autopilot is steering; the needle shows how far off the selected heading it's actually doing, which should be zero but isn't always. Helps you understand how the pilot is coping and whether the sail balance might need tweaking. Finally, you can press a button to tell you what the average heading actually steered was, so that in the days of dead-reckoning the navigator could do a better EP.

Have to say I don't find the use of numeric digits particularly intuitive on the OP's screen, but appreciate it's a lot easier than trying to do graphics :)

Pete
 
Pete's right, this is just a pure indicator.
In fairness it's more an exercise in seeing what I can do. The main thrust was to get AIS to my iPad and having done that I decided to use a few spare sensors :)

So: theres some visual work to do, the fonts are ugly but with the uTFT library you are limited to gopping fonts, I'm going to make up my own bitmaps in illustrator and use those instead I think.

The Course to Steer is simply a hit and go. Its designed as an aide memoir for crew helming. The GPS is providing SOG information but the snap must have either hit a refresh on screen or its glitched - either way that part works, just looks fugly.

I should add: this is in place of a bulkhead compass. Hence the need for the numbers.
 
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My interpretation of your display is that your heading is 260 [True, Magnetic or Compass?], and that the arrow indicates that I should be steering to Port to a heading of less than 260. Not sure about the meaning of CTS [course to steer] being 285 - or is that COG [course over ground]?

Aaaah, I thought about this. It's the direction to push the tiller! The heading is a pure output from the compass and could easily be switched between modes simply by having a setting function to add/subtract the required degrees. My gut feeling however would be to use the compass output becuase if you were using a bulkhead compass you'd have exactly the same issue.

Its up to us as navigators to know what course to steer I guess!
 
Aaaah, I thought about this. It's the direction to push the tiller! The heading is a pure output from the compass and could easily be switched between modes simply by having a setting function to add/subtract the required degrees. My gut feeling however would be to use the compass output becuase if you were using a bulkhead compass you'd have exactly the same issue.

Its up to us as navigators to know what course to steer I guess!

In that case the CTS value makes sense. I would not assign the arrow direction using the convention you have chosen. I would think the direction to move the boat's head would be more intuitive, and a novice helming with a tiller would adapt very quickly. But that's just me. [I assume you don't have a wheel?]
 
I'm thinking a setting to choose the type of heading correction style, either push this way or head this way... Tiller of course being opposite to wheel only use would be for tiller on push this way.

I'm not taking the whole device too seriously, I have it doing what I wanted now, everything else just makes it a potentially useful toy - and quite a neat learning tool for the kids.
 
I'm thinking a setting to choose the type of heading correction style, either push this way or head this way... Tiller of course being opposite to wheel only use would be for tiller on push this way.

I'm not taking the whole device too seriously, I have it doing what I wanted now, everything else just makes it a potentially useful toy - and quite a neat learning tool for the kids.

Good plan!
 
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