OpenCPN SIMRAD/LOWRANCE Radar Overlay PlugIn

[rgleason]

Merrimac, Hakan, Matt, and others. I am thinking of replacing my 25 yr old Autohelm Radar which is backstay mounted gimbaled Waltz pole. I like the instant on/off and low power requirements of Navico Broadband Radars, however these radars domes are phyically bigger and higher by 1"-2", and weigh about 4 lbs more than my old one. The boat is a Bristol 32' with a 22' waterline length. The radar platform is about 9.5' above the deck, say 12' above the water, so the effective range is about 12nm depending of course on the height of the distant ship, so being able to see 36nm is kind of meaningless! --Should I wait for a smaller diameter & lighter broadband radar (which may never happen) or just go ahead with it?
PS: The Garmin 18HD Pulse Radar is a little shorter in height but is not quite as good on power use and instant on.
PSS: Obviously weight in the ends of our boat with short footprint is not good due to tendency for hobby horsing in steep chop waves of a certain length, and requires heading off 5 degrees. We have not found this to be a significant problem except very occasionally.
PSSS: I forgot to thank you all for your programming and testing on the plugin! This looks like a very real option now.

[merrimac]

Originally Posted by rgleason

Should I wait for a smaller diameter & lighter broadband radar (which may never happen) or just go ahead with it?

I wouldn't hold my breath for that coming out of Navico. Physically it needs two antennas on top of each other. After spending a reported USD 10e6 on R&D I think they'll want to recoup the investment first.

4G is worth the relatively little money over 3G, and both are definitely better than BR24 at long range.

[merrimac]

rgleason,

You could consider lowering the radar a bit? No harmful rays to fry your brain on these. That way you could compensate for the increased weight.

[NahanniV]

I'm getting ready to order a 4G scanner and would like to confirm that the firmware version that I am buying will work with this plugin.

It is the latest FW:

Version 4.1.57
Release Date December 20th 2012

Anyone running with this version ?

Thanks,
JM.

[merrimac]

I've got 4.1.57 as well. Works fine.

[Baikal]

for more information about the plugin

1. The radaroverlay works without a compass data that is Available only at the COG from the GPS receiver?
2. ARPA function is supported?
3. over WiFi is possible to obtain radar data?

Windows platform

[merrimac]

Originally Posted by Baikal

1. The radaroverlay works without a compass data that is Available only at the COG from the GPS receiver?

1. No. COG is just not the same as heading.

Originally Posted by Baikal

2. ARPA function is supported?

2. No.

Originally Posted by Baikal

3. over WiFi is possible to obtain radar data?

3. No.

[merrimac]

Originally Posted by Baikal

3. over WiFi is possible to obtain radar data?

I've experimented with setting my WiFi bridge to pass through the radar data as multicast data, but that does not work very well as it is always sent out at 1 or 2 Mb/s so it consumes almost all of the capacity of the link and just doesn't work very well. For now I have given up on wireless, and use a USB ethernet dongle with my tablet.

Maybe some form of VPN would be a nice workaround. But it doesn't make matters easier, and I want easy-and-always-working for stuff like this.

[RobbieW]

Originally Posted by Baikal

...
3. over WiFi is possible to obtain radar data?...

See post 43 in this thread but note that I was wrong about data volumes, they are much less than thought (posts 57 & 58). I have this working though you need to want to have a router as an integral part of your instrumentation, be prepared to install alternate firmware to the manufacturers standard and do some customisation.

[rgleason]

From RobbieW's post -Broadband Radar over Wifi - considerations & tests

Post 43

Muttnik pointed out to me that UDPXY was unlikely to be the answer for the reasons you observe - that its mostly a solution for uni-directional traffic to specific clients rather than the scatter gun of broadcast. Quite why the Navico developers chose that technology for thier implementation with 2 way traffic is beyond my understanding.

I dont know how many I speak for, but for me it would be great to be able to have everything wireless on the boat. I understand there may obstacles in the way of data volume and the strange implementations of OEM developers but its fun to try and find ways around those and end up with an 'open' system.

Also Post 47 is good information Muttinik

...not left with the impression that high-rate multicast over wireless is generally now "fixed" for heterogeneous networks. 802.11aa seems to address it but doesn't seem to be widely implemented. Am I missing something or are you simply saying that clever/expensive routers should have the ability to specify the PHY used for multicast (which would be handy but I'm not aware that that is standard)? Happy to be educated here....

On a practical note, given that the receiving socket in the plugin binds to INADDR_ANY it should be possible to fire unicast UDP at the machine running OpenCPN assuming you know its address: the receiver won't care if the packet is multicast, broadcast or unicast as long as it's to the right port. Control messages from the plugin to the scanner shouldn't be a problem rate-wise. Probably a number of ways to go from multicast to unicast on the wired network (socat? packet mangling on the router?) and keeping the multicast off the wireless network (packet filtering? using the opencpn machine's firewall to block outbound igmp if the router supports igmp snooping?) but not really a trivial fix.

Post 48

..research done so far; an ASUS RTN16 running Tomato (Version Shibby 1.28.0000 MIPSR2-117 K26 USB VPN) with some configuration changes to IGMP/Multicast will allow the multicast from the scanner through to OpenCPN over wireless. The router is configured to run 11N only for wireless connections, to give it a fighting chance of handling the data volume. It also has 4x100Mb ethernet ports.

Post 57

According to the Windows taskmanager network LAN utilization is on 3% of 100 Mbps, so much lower than I find in other posts.

Post 58

My router gives data in kbits/sec, it was recording a peak of 1500 kbits/sec with a 3G radar on 1/2 mile range just now. If I have the math right this time, thats about 190 Kb/sec. I'm pretty sure I've seen peaks of 6000 kbits/sec previously but even that comes in under 1 Mb/sec.

[rgleason]

I'm trying to understand why use a VPN, isn't that more overhead with encryption etc?

Sent from my SCH-I545 using Cruisers Sailing Forum mobile app

[NahanniV]

I would also like to be able to have a WiFi connection to the scanner.

My plan is to try bridging the Ethernet connection from the scanner to the WiFi connection in my Linux computer.

Cheers,
JM.

[RobbieW]

Originally Posted by merrimac

...This is the first release made using the new OpenCPN plugin packaging system that makes it much easier to install -- download the .exe/.rpm/.deb/.dmg and run it!

Get it here: opencpn-navico-radar-plugin.github.io

Just installed the Ubuntu .deb package onto a 14.04 system now running OCPN 3.3.2316. When opening 'Options' the first time after each load of OCPN I'm getting an error message. The message displays for about 30 secs then disappears & I'm too slow to transcribe it in full. In essence the message references '/usr/lib/opencpn/libbr24radar_pi.so' and tells me that it is incompatible with the current version of OCPN, it shows the plugin as Version 0.95.

[nohal]

Robbie...
The deb package really is 1.0, so it looks like you still have an older version installed...
Try

sudo rm /usr/lib/opencpn/libbr24radar_pi.so
sudo dpkg -i ~/Downloads/br24radar_pi_1.0-1_amd64.deb

I suppose you saved the downloaded package in the standard Downloads folder
Any errors? Did it fix the problem?

Pavel

[RobbieW]

Originally Posted by nohal

Robbie...
The deb package really is 1.0, so it looks like you still have an older version installed...
Try

sudo rm /usr/lib/opencpn/libbr24radar_pi.so
sudo dpkg -i ~/Downloads/br24radar_pi_1.0-1_amd64.deb

I suppose you saved the downloaded package in the standard Downloads folder
Any errors? Did it fix the problem?

Pavel

Hi Pavel,
Its a new install for the radar plugin (I run both Widows and Linux, whilst away from the boat this winter I've upgraded my Linux partition). I'm running the i386 version so ran your two commands but edited the dpkg command. No difference