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Data Logging

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flymustangs

Well Known Member
I'm wondering how important this feature is in engine monitors or monitoring an engine in general. The latest issue of Kitplanes has a couple of articles about engine monitors and makes a big point of being able to log data either stored on the box or streamed to a laptop. All the monitors reviewed had this capability in one form or another.

How many of you use this feature on a regular basis? Have you detected any problems in it's early stages like the Kitplanes article supposes?

Thanks.
Ken
 
It's a very useful feature if you want to balance your fuel injectors. I have done that on occasion (still need to get out and try a new smaller set that Don from AFP sent me...). Being able to sit in the comfort of your home or hangar and review every second's worth of EGT data, well, that's pretty neat. And there's no other way to get as accurate a record of the data than recording it.

Also, if you have some sort of quirk that comes up during flight and you have your hands full either getting the airplane on the ground or otherwise, it's nice to know you can always "review the tape" later, when it's safe, to figure out WTF happened.

During engine break-in you can record your flights' data and then correlate trends over time.

Obviously I'm a fan of data recording. Good stuff!
 
Ken, data logging is great

I wish that I could get data logging off of my EFIS as well as my Engine monitor. It is close to impossible to all the number written off the screen and on to your knee board before some of them change. This is usually not critical, but it is nice to know if you have a consistent data set when analysing performance.

Kent
 
GRT Does it!

kentb said:
I wish that I could get data logging off of my EFIS as well as my Engine monitor. It is close to impossible to all the number written off the screen and on to your knee board before some of them change. This is usually not critical, but it is nice to know if you have a consistent data set when analysing performance.

Kent
Click to expand...


One of the great features of the GRT EFIS - full data logging off of the EFIS, so not only do you get all of the engine data, but all of the flight parameters as well. Plug a thumb drive into the USB port, go fly your test card, go home with the thumb drive, plug it in to your PC, and sit back with a cold one while you manipulate the data. :cool:

Sure beats trying to write it all down in real time - and I've been trained to do that!

Paul
 
Data logging is outstanding, and should be a standard feature of any digital engine monitor. Once you have the data, you'll be amazed at how indispensable it really is.

While I love my Dynon D-180, I really feel they've underestimated the value of datalogging, so I whine to them every chance I get about it. I would suggest that anyone looking to buy a Dynon should call them and tell them it's a feature you require.

Even if they won't add it, at least they do output all the data, and you can log it (engine and flight info). I've got an RS-232 datalogger in my RV-8 that captures all this info, and records it to SD memory cards. What's missing is a really slick program to display it all, but Excel does what I need it to do.

Cheers,
Rusty (nagged Tracy Crook too <g>)
 
kentb said:
I wish that I could get data logging off of my EFIS as well as my Engine monitor. It is close to impossible to all the number written off the screen and on to your knee board before some of them change. This is usually not critical, but it is nice to know if you have a consistent data set when analysing performance.

Kent
Click to expand...

Kent, I do have datalogging, but sometimes it is quicker to shoot a quick set of digital photos. "Point and shoot" digital cameras have plenty of resolution these days, and I have imported a series of photos into the computer, and opened a spreadsheet in a second window, and typed the numbers straight into the spreadsheet. This is quick, and I don't have to remember to bring my memory card to the airport (I almost always keep the camera in my back pocket).
 
Record Playback

Another simple option (at least with GRT) is to connect a memory stick, select 'Record', carry out the flight test, land, shutdown and then select 'Playback' and write down the data.

All info plays back. PFD (Primary Flight Display), ND (Nav Display) and Engine Monitor (Which is actually much more than an Engine Monitor as it supplies a lot more info than just that on the engine. ie. Flight time, flap position, Fuel level, endurance etc. Its really an EICAS (Boeing) or an ECAM (Airbus). Unfortunately, Engine Monitor has stuck!

Anyway, the whole flight is there to be played back. Fabulous; except you find out how poorly you held the airspeed and the altitude.

Pete.
 
[Plug a thumb drive into the USB port, go fly your test card, go home with the thumb drive, plug it in to your PC, and sit back with a cold one while you manipulate the data. :cool:

Paul,
I am ready to do my first flight Friday Mar. 16. I have been trying to get my GRT Horizon 1 to record to my USB memory and don't seem to be having any luck. The GRT will read from this stick so I assume it will write to it.

Can you please give me a button push sequence to start and stop the recording?

Thanks,
Duane
 
GRTDecode

Hi,

A detailed sequence of screen shots is along side the GRTDecode application. Details at http://www.rvproject.gen.nz/grt/

GRTDecode will extract Engine data, flight profile / attitude data and GPS data (and render in Google Earth).

Current version hasn't changed for about 6 months, a misc update is nearly ready, but just helps with a couple of strange GPS decoding problems. Any problems let me know.

Regards,

Carl
 
One more question

Thanks Carl,
I did all that, but maybe my problem is that I don't know which file name to look for when I plug the thumb drive into the computer.
What is the file naming scheme for the GRT?


Duane
 
Duane,

The file will go in the root directory of the thumb drive, and will be called "DEMOxxxx..LOG, where "xxxx" will be the next available number based on what's in the directory. Let us know if you don't find that. Also, remember that you have to STOP recording before you shut down the EFIS, or it won't write the file to the drive....

Paul
 
New SD Data Logger product

This thread is perfect timing. I have been working on a SD Data Logger for the past couple of months. This is a circuit board about 2" x 4" with a single DB15 connector that provides +12V, Gnd and 4 serial input and 2 serial outputs and microcontrol Rx/Tx. This board is capable of receiving data from 4 rs-232 devices in your plane and create a single file on the SD Flash card at 1 second intervals. This way all the data from all 4 sources are corrilated together in time. While I am still working on the software, it is currently installed in 2 RV's and we are testing it right now. The system is upgradable via flash as well, so new software willl be available as I write more parsing routines for the different equipment. So far I have it parsing the Dynon EFIS, Dynon EMS, Grand Rapid EIS, GPS NMEA format using $GPRMC sentence. I am curring working on the Aviation format of the Garmin 430/530. What is really cool about this data logger is it is small and very easy to remove the SD Card after flight and open the engine data in Excel to graph or open the GPS data using GPS Visualizer for a file for Google Earth. Please let me know how much interest there might be in this device as I am current trying to figure out if I should market it and for how much. I have 3 made already and 6 more on the way. You can contact me offline at [email protected]

Thanks Ray Doerr
N519RV
RV-10 flying 220 hrs.
 
Ray,

I would potentially be interested in the product WITHOUT any parsing. Just storage.
 
rdoerr01 said:
Please let me know how much interest there might be in this device as I am current trying to figure out if I should market it and for how much. I have 3 made already and 6 more on the way.
Click to expand...
I'm interested, depending on the eventual feature set. I have Dynon EFIS, Grand Rapids EIS and GNS430. But, depending on what type of testing I am doing I want to be able to select other sample rates - up to 4 samples per second.

I also have an event marker - a momentary switch on the stick sends voltage to pin 1 of a serial port, which is picked up by software as Carrier Detect. I've got provisions for up to three more discretes, using pins 6, 8 & 9.

I've been playing around with recording raw GPS data from an Antaris LEA-4T GPS, in the hope of getting sub-metre accuracy with post-processing, using corrected satellite orbits. But while this works nicely with $10,000 survey-quality GPS units, my initial testing with a $400 GPS has been disappointing. Too much noise in the data. I've got a couple of more troubleshooting steps to take, but I'm not optimistic.

I may also acquire a $100 LabJack U3 to record analog inputs (flight control positions, thermocouple temperatures, etc), but this is a USB device, so it wouldn't be compatible with your current hardware.

At the moment I am planning to record all this stuff using a laptop, with a custom Python script to take care of time syncing the data. But replacing the heavy laptop with a light box is tempting. What software does the controller on the card use? I doubt you want to write software for my very unique requirements, but maybe I would purchase the hardware, and write my own software.
 
Gary Bricker

I am setting up forums at Southwest Regional Fly-in and this could be a good one. If someone would like to do one on June 1st and or the 2nd let me know. Also anyone who has good forum material and would like to do one on that let me know. No books sales or sales pitches, just good training info.
 
Kevin Horton said:
...I want to be able to select other sample rates - up to 4 samples per second... I also have an event marker - a momentary switch on the stick sends voltage to pin 1 of a serial port, which is picked up by software as Carrier Detect. I've got provisions for up to three more discretes, using pins 6, 8 & 9.

I've been playing around with recording raw GPS data from an Antaris LEA-4T GPS, in the hope of getting sub-metre accuracy with post-processing, using corrected satellite orbits...

I may also acquire a $100 LabJack U3 to record analog inputs (flight control positions, thermocouple temperatures, etc)... custom Python script to take care of time syncing the data...
Click to expand...
Makes me feel pretty silly, you know, just looking at an airspeed indicator or altimeter. Flight control positions? Thermocouples? Sub-metre accuracy?

Well I guess you're going to know your airplane Kevin!
 
Kevin, the hardware uses a Microchip microcontroller and a 4 channel 64 byte FIFO UART. This UART is the key to being able to capture the data as well as the firmware is all written in assembly for the faster possible speed. In all my testing I have not found a laptop yet that can keep up to logging the data from the Dynon EFIS without dropping 2 - 3 messages a second. The Dynon EFIS sends 53 bytes 64 times a second at 115,200. That equates to about 30% line utilization. This hardware is able to keep up to this data on a single port at line rate and with all four ports in use it will log to a single file the latest messages from all four ports at a interval of 1 second. I am working on making this configurable, but I think the minimum would be 1 second. Small is likely possible, but I would need to test it. The slowest part of the system is the writing to the SD Flash card. This write has to complete before the new incoming data overwrites it in memory, which is limited.

Thanks Ray Doerr
 
rdoerr01 said:
Kevin, the hardware uses a Microchip microcontroller and a 4 channel 64 byte FIFO UART. This UART is the key to being able to capture the data as well as the firmware is all written in assembly for the faster possible speed.
Click to expand...
Assembly - Ugh. You're a better man than I. I'll drop the idea of doing my own software for your device.
rdoerr01 said:
In all my testing I have not found a laptop yet that can keep up to logging the data from the Dynon EFIS without dropping 2 - 3 messages a second. The Dynon EFIS sends 53 bytes 64 times a second at 115,200. That equates to about 30% line utilization.
Click to expand...
I haven't had any problems with three different Mac laptops, starting with a 300 mHz G3 iBook. But, I'm feeding the four serial streams into a Keyspan four port USB to serial adapter, and then feeding the USB cable to the laptop. No dropped data lines in ground tests up to 30 minutes duration. I haven't flown it yet.
 
Montoring

Has anybody been able to monitor and record AOA with the Dynon D-10A? Has anyone had experience monitoring flight data with the AFS 3400 or 3500? I will have both in my -8 and will likely choose one unit for monitoring. Thanks for any input. Bill
 
Bill Dicus said:
Has anybody been able to monitor and record AOA with the Dynon D-10A? Has anyone had experience monitoring flight data with the AFS 3400 or 3500? I will have both in my -8 and will likely choose one unit for monitoring. Thanks for any input. Bill
Click to expand...
On the D-10A, all the data is spit out as ASCII text on the serial line. The data format is described in the operator's manual. It is easy to record, as long as your setup can handle 64 records per second at 115,200 baud. Once you have the data, you could import it into Excel and tell it which characters are which pieces of data. Or, you could use one of several programs that are available to decode the data. You can find more info on the free programs that people have made by searching on Dynon's forums.

Vern Little has made a little box that decodes the AOA data and drives a series of LEDs that he has mounted on top of his glare shield. This allows him to monitor the AOA without bringing his eyes into the cockpit.
 
Ray,

Any updates?

--
Michael


rdoerr01 said:
This thread is perfect timing. I have been working on a SD Data Logger for the past couple of months. This is a circuit board about 2" x 4" with a single DB15 connector that provides +12V, Gnd and 4 serial input and 2 serial outputs and microcontrol Rx/Tx. This board is capable of receiving data from 4 rs-232 devices in your plane and create a single file on the SD Flash card at 1 second intervals. This way all the data from all 4 sources are corrilated together in time. While I am still working on the software, it is currently installed in 2 RV's and we are testing it right now. The system is upgradable via flash as well, so new software willl be available as I write more parsing routines for the different equipment. So far I have it parsing the Dynon EFIS, Dynon EMS, Grand Rapid EIS, GPS NMEA format using $GPRMC sentence. I am curring working on the Aviation format of the Garmin 430/530. What is really cool about this data logger is it is small and very easy to remove the SD Card after flight and open the engine data in Excel to graph or open the GPS data using GPS Visualizer for a file for Google Earth. Please let me know how much interest there might be in this device as I am current trying to figure out if I should market it and for how much. I have 3 made already and 6 more on the way. You can contact me offline at [email protected]

Thanks Ray Doerr
N519RV
RV-10 flying 220 hrs.
Click to expand...
 
Just a bit of info for those that may have missed the update. The Dynon EMS series now supports data logging as of the 3.0.0 firmware. It works great!
 
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