The Combine Forum banner

1 - 20 of 412 Posts

·
Registered
Joined
·
318 Posts
Discussion Starter #1
So after going thru a few other threads I've decided I'm going to try to come up with a cheap rtk setup for my spray tractor and for use in a ute when towing a weed wiper (which we are in the process of making). I will be using a tablet for my guidance display (using either a commercial app or agopengps). I am aware it's only guidance and why would I bother with rtk and only L1 for that matter? I like a bit of a challenge and with what I'm thinking of using it will hopefully work out cheaper than a novatel receiver. As much a novatel would be nice and easy, it is stretching the budget and I can get as good accuracy with hopefully a smaller price tag.

So the plan is....either a drotek tiny rtk receiver setup (thanks for torriem for putting us onto it) or an Emlid reach rtk setup using a jdrone rf900 plus long range as radio. Both of the receiver setups are gnss enabled so will make use of beidu etc. They will hook it into my tablet to feed it nmea strings. Currently all of this technology is being used in drones/uav's so with a bit of luck it will be a case of plugging each item in to configure it, hook it all together and then turn it on and away we go. I realise it will most likely entail a heap of stuff around, playing with different settings to get it going but I've got a plan which is the main thing.

Autosteer/rate control might come down the track but I'm not worried about that at the moment.

Don't expect this to be fast moving because getting parts shipped to aus may take a while, especially if I order the wrong thing because this is my first electrical project.

Any comments/suggestions are appreciated.

Cheers
 

·
Registered
Joined
·
5,831 Posts
Awesome, one more piece of the puzzle.

Make sure the tablet you get can charge while it is also using the USB. Its a limitation for many tablets.

AgOpenGPS runs only in Linux and window$, but tablets are couple hundred bucks, and then you have another tablet anyways.

Looking forward to following this.
 

·
Registered
Joined
·
4,469 Posts
Theres heaps of tablets running windows 10...if u want cheap or to check out.

GearBest: Online Shopping - Best Gear at Best Prices

Online Shopping for Cool Gadgets, RC helicopter & Quadcopter, Mobile Phone, Fashion at Banggood.com

AliExpress.com - Online Shopping for Electronics, Fashion, Home & Garden, Toys & Sports, Automobiles from China.

Ive used ali and gearbest sites...works fine..

I like the techlast tabs

Alot of dual boot with windows and android...trick is u cant update any versions..

Ant...
 

·
Registered
Joined
·
318 Posts
Discussion Starter #5
So I've been doing some research. The emlid reach rtk (which uses the same chip as the drotek tiny rtk) looks like it might be a good option. It can either communicate via serial or Bluetooth so depending on what else the tablet is doing you should have some flexibility. A emlid reach setup is $570usd so it's going to be the dearest part in the project I think (depending on what tablet/s I get)

I know my autofarm A5 rtk runs on a freewave fgr 900mhz radio. I'm aware of pacific crest and satel radios being used on other systems but these are horridly expensive. I'm trying a Rf design 900+ 900mhz radio which are reasonably affordable. It may require a bit better antenna in order to get good range but that's alright imo.
 

·
Registered
Joined
·
3,830 Posts
Our Fieldnet pivot system uses off-the-shelf 900 Mhz radios to communicate for several miles (the base station can go about 6 or 7 miles). I think they use normal XTend 900 Mhz modules, 1 watt.

Another possible solution is a simple app on a cell phone that communicates via the internet with your base station, and talks over serial or bluetooth to the RTK receiver. A bit more complex though.

I have a couple of Trimble integrated autosteer units, currently using just WAAS. I know that the steering computer actually talks over RS232 to the receiver, but it uses a proprietary trimble protocol that is partially documented. But I was thinking that an arduino could intercept data from the receiver, decoding it just enough to find the frames with GPS position data in it, and then substitute data from the RTK receiver, and then pass it on to the nav computer. The nav computer would still think it's using WAAS, but it would be fed a very precise, repeatable RTK signal.

Basically I'd love it if I could use a cheap RTK receiver to provide navigation data to existing autosteer solutions that I already have, but unfortunately everyone is all proprietary and locked up so that they can cash my checks each year.
 

·
Registered
Joined
·
318 Posts
Discussion Starter #7
Our Fieldnet pivot system uses off-the-shelf 900 Mhz radios to communicate for several miles (the base station can go about 6 or 7 miles). I think they use normal XTend 900 Mhz modules, 1 watt.

Another possible solution is a simple app on a cell phone that communicates via the internet with your base station, and talks over serial or bluetooth to the RTK receiver. A bit more complex though.

Basically I'd love it if I could use a cheap RTK receiver to provide navigation data to existing autosteer solutions that I already have, but unfortunately everyone is all proprietary and locked up so that they can cash my checks each year.
The rfdesign 900+ radio is a 1 watt radio which looks very similar to the xtend radios. I checked out the whole correction by cell but it's a fair bit more complicated.

A lot of screens now will accept GPS from an external source so in theory you should be able to use this setup to stream rtk into your existing autosteer screen.
 

·
Registered
Joined
·
318 Posts
Discussion Starter #8
Theres heaps of tablets running windows 10...if u want cheap or to check out.

GearBest: Online Shopping - Best Gear at Best Prices

Online Shopping for Cool Gadgets, RC helicopter & Quadcopter, Mobile Phone, Fashion at Banggood.com

AliExpress.com - Online Shopping for Electronics, Fashion, Home & Garden, Toys & Sports, Automobiles from China.

Ive used ali and gearbest sites...works fine..

I like the techlast tabs

Alot of dual boot with windows and android...trick is u cant update any versions..

Ant...
Dual boot would be handy. Apart from on my PC, I've never used a windows tablet. Mind you, I've got an iphone and iPad so no exposure to android devices either. Is there any advantages in either windows or android os's? I've had a look at the irulu tablet (mentioned in agopengps thread) I am aware agopengps only runs on windows but there are plenty of apps already out there for android.
 

·
Registered
Joined
·
4,469 Posts
I have both ipad and android...hate ipad witha passion..clunky POS...it was a left over from the divorce...will be a dinner matt soon...

Acer have an R3 and A200 tablet that i think takes charge and has usb at same time

Chuwi Hi12 Tablet PC-259.89 Online Shopping| GearBest.com

I like this tablet, ive been looking into for a while, i need to charge and out put at the same time, for my IK multi media guitar dongle, nothing worse than practicising and then stopping to charge, it chugs the power when using the dongle as well...

I would also like split screen, the surface pro splits 4 ways, 2 would be handy...that way you can be streaming in live data while doing the job...for guitar 4 would be neat, 1 for ik app, 1 for youtube lesson, 1 for tab pro, 1 for whatever...the BOM....but its $1,100 and battery life is crap apparently.

The only downside to dual boot is updates, the wondows 10 is designed to work with that android system and thats it...might not be a biggie?

Ant...
 

·
Registered
Joined
·
318 Posts
Discussion Starter #10
I have both ipad and android...hate ipad witha passion..clunky POS...it was a left over from the divorce...will be a dinner matt soon...

Acer have an R3 and A200 tablet that i think takes charge and has usb at same time

Chuwi Hi12 Tablet PC-259.89 Online Shopping| GearBest.com

I like this tablet, ive been looking into for a while, i need to charge and out put at the same time, for my IK multi media guitar dongle, nothing worse than practicising and then stopping to charge, it chugs the power when using the dongle as well...

I would also like split screen, the surface pro splits 4 ways, 2 would be handy...that way you can be streaming in live data while doing the job...for guitar 4 would be neat, 1 for ik app, 1 for youtube lesson, 1 for tab pro, 1 for whatever...the BOM....but its $1,100 and battery life is crap apparently.

The only downside to dual boot is updates, the wondows 10 is designed to work with that android system and thats it...might not be a biggie?

Ant...
Can't see the windows thing being an issue. I think I will order one of those today ant. It's not like it's $1000 like an apple or Samsung tablet. Will see how it goes.

Also going to order a emlid reach rtk kit. Gone this way over the drotek tiny rtk because the emlid has Bluetooth and wifi connectivity as well as serial. Just a bit more flexibility.
 

·
Registered
Joined
·
4,469 Posts
Can't see the windows thing being an issue. I think I will order one of those today ant. It's not like it's $1000 like an apple or Samsung tablet. Will see how it goes.

Also going to order a emlid reach rtk kit. Gone this way over the drotek tiny rtk because the emlid has Bluetooth and wifi connectivity as well as serial. Just a bit more flexibility.
Some people at the Mine from Sydney have Chuwi tablets and Xoimi (Spelling) phones and love them...i will get a Chuwi tablet before xmas...would be cool if i can tie this in for guidance...and would be awesome if it could run an ezi steer electric steering wheel of the sorts.

I assume you have to make sure the tablet window settings don't auto update? And if in future it does need an update i'm not sure if it affects 1 or both programs, i don't know if one has priority?

The Acer ones arent expensive either 3-400 bucks so check R3 and A200 as well...see what you reckon.

I have not tried any of them to make sure they will charge and run device but all the research i done about guys doing data collection in the states and needing it to charge up out of there pick up points towards it being able to do it....

If the device you are running has a battery there are some reports the charging will bypass the tablet and charge the device?

Ant...
 

·
Registered
Joined
·
3,830 Posts
Definitely keep us posted on the emlid reach. I'm interested to hear your experience it getting it set up and running.
 

·
Registered
Joined
·
5,831 Posts
Gonna echo that! 570$ US for RTK cm level accuracy. Yes please. All open source.

Even has built in IMU.

Ran the GPS receiver over bluetooth today on the tablet. Worked great, even 50 feet away.
 

·
Registered
Joined
·
318 Posts
Discussion Starter #14
All components are ordered :)

Emlid reach rtk kit
Rf design 900mhz radio kit
Chuwi dual boot tablet

Going to get a weatherproof enclosure for base GPS and radio to go in and a pretty box of sorts to go inside the tractor cab. Will try to do something similar to a uhf radio aerial for the rtk radio.
 

·
Registered
Joined
·
318 Posts
Discussion Starter #16
Someone now needs to 3D print an outdoor enclosure/mount.
As cool as it would be to 3D print an enclosure, I've gone the cheats way out and bought one off eBay. Also ordered bulkhead cables for each necessary connection to make it fairly weatherproof. From what I'm lead to believe the emlid reach unit uses a mcx connector, which isn't my connector of choice but I might have a way around it yet but we will see.

Cheers
 

·
Registered
Joined
·
318 Posts
Discussion Starter #17
So after a long day servicing a windmill that wasn't pumping, I arrived home to a few surprises sitting on the kitchen bench. The emlid reach rtk kit and rf design 900+ radios have arrived :) i only opened boxes and had a look, didn't plug anything together but the emlid community has a crapload of threads on hooking reach units up to radios which will be handy. There are some YouTube clips but they tend to use 3dr radios. I didn't realise just how small they actually are until they arrived, dimensions listed on a website are hard to comprehend when it's so small. I've reused the lid off my beer as a reference to give people an idea. Once I start plugging things together and mounting things up it will get a little more interesting.
 

Attachments

1 - 20 of 412 Posts
Top