LOLO5 PC software

Before data download

Let’s make definitions before downloading data from logger.

  1. Select “File” and “Options” (CTRL+O)
  2. Options dialog will pop-up. Check correct COM number (corresponding to your virtual USB/COM port).
  3. Define name of downloaded files. Will be numbered from 1 to x.

Downloading data

Now we are ready to download data

  1. Select “Data”, “Read data” (CRTL+R).
  2. Connect LOLO to USB interface and press “Connect” button within 10seconds. Red light (right site of Disconnect button) should become green; LOLO is connected. Logger is during PC communication powered by USB interface, don’t switch on your model (receiver). You can download data when recorder is in model installed (this was reason for long port nr.3 data cable) or when it’s out of model.
  3. Using Voltspy configuration you can define voltage alarms for on board small LEDs or for Jeti Duplex display (JetiBox). My favorite value is 5.0V, will warn me early enough.
  4. You can also check firmware version

  1. When you select “Read Data”, download will start…
  2. After downloading all records in LOLO5 you will see list of new files.
  3. Now you can select “Disconnect” or you can “Erase Memory” (4). Memory can be also erased from JetiBox menu.

Organize data, main toolbar and display zones

After download you can organize (drag&drop) files to folders, delete unwanted records etc. Sometimes these basic file operations are faster to do direct in windows explorer. Now we can start to analyze one flight (see picture bellow).

  1. Double click any file/flight in preview zone and …
  2. …it will jump to active zone. Here you can also select (check box) to preview power supply voltage log, servo log and annotations. Flight information can be also added.
  3. Measurement zone, here you can see results from click&drag in measurement mode.
  4. Graph zone

List of buttons in graph upper area:

  1. Copy graph to clipboard
  2. Save graph as *.BMP
  3. Print graph
  4. Setup graph attributes
  5. Zoom out
  6. Default view (cancelling all zooms), when you move with left mouse button down from right site to left site of graph you will also get default view
  7. Zoom in, when you move with left mouse button down from left site to right site of graph you will also get zoom in
  8. Measurement mode; click&drag to crosses and view result in measurement results window
  9. Place annotation
  10. Add cross hair to mouse pointer
  11. Show zero line for servo log
  12. Show/hide measurement results window
  13. Show/hide legend

On picture bellow you can see how voltage drops during F3B zooming from 5,1V to 4,8V (-0,3V drop). Also you can notice approx. 10mm snap flap movement down at zoom-end. Bellow I will explain how to calculate this. LOLO5 in this case is hooked via Y Cable to left flap on my F3B model.

Flight analysis

Servo log

Theory: We are actually logging length of servo impulse and converting to percentage using AD (Analog to Digital) converter. As standard we can say that 1,5ms is equal to zero servo position i.e. neutral. 2ms is +100% and 1,0ms is -100%. Bear in mind that no function (mixers, expo etc.) has any influence to length of impulse i.e. what we are logging. These mentioned functions of modern transmitters just influence “behavior” of your stick.  I’d like to say e.g. -50% deflection is equal to 1,25ms regardless of your stick position. In others words we don’t record stick position.

Now imagine, we will log elevator servo. In neutral (1,5ms) graph will show 0 (zero), let’s pull to max and graph will show e.g. +120%, now let’s push to max and graph will show -120%. This is valid if my elevator moves symmetrically.

When I pull to maximum it’s equal to 10mm (number +125 in graph) up deflection. When I push to maximum it’s equal to -10mm (number -125 in graph) down deflection. It’s easy to say that when I log this elevator servo (LOLO5 hooked on this servo using Y-cable) everything on graph multiplied by 10/125=0,08 is deflection of servo in millimeters, e.g. -50 is -50*0,08=4mm. Eeeh, not so easy…

Reality: Above I explained how we try to calculate deflection on elevator servo. Everything would work fine if movement of servo arm has linear dependence of moving elevator flap . This is very often not true while not always servo arm and flap arm has same length. Not even talking about RDS (Rotary Drive System). Fortunately these non-linearities are visible in big servo deflection and we are mainly interested in small deflection around zero. In this case servo log works nice and can help you in your model setup.

On log bellow you can see F3B model Dingo elevator servo record. Here is situation a bit complicated while it has V-tail i.e. no dedicated elevator servo (servo is working also as rudder). But let’s keep it simple and we will say it’s ordinary elevator servo. Sure you could select servo where pulling up is increasing in graph numbers although it’s not necessary.

I was logging elevator servo nr.4 (JR/Graupner system) positions on all F3B flying phases.

  • Double left click to activate flight008 (1). You can note that Altitude check box (1-st one) is not active, it’s better for this example not to overlay more graphs inside.
  • This servo level (2) is zero position on my elevator-flying phase Zero. Maybe you will find that it doesn’t correspond to 0 (zero) on Y axis. It’s normal. For example when you will log flap servo on wing I have offset around 110%. But back to elevator log. I want to have servo level in zero position to be zero on Y axis (Rx(x)).
  • Select servo zero level icon on toolbar (3) for better orientation in graph. You can also zoom-in area around zero level flying phase (2).
  • Now using slider (6) you can set zero flying phase to be really zero. You can also input direct offset value (5) in Rx channel field. You have also option to right-click on zero flying phase level and from context menu select Adjust Rx to (x,0).
  • Now zero flying phase is really in zero. You can place zero line in the middle of Y axis-check box Rx center (4)
  • I measured that in zero flying phase (12) deflection of elevator is +- 6mm. I see on graph it corresponds to +-29. Constant will be 6/29=0,206 cca 0,21. Maybe you can ask why I didn’t measured movement of elevator in Duration flying phase. Well, I could, result will be nearly the same. On big deflections I expect non-linearities (and there are as I found on my bended Dingo’s elevator arms…)
  • After flying phase Zero (2) there are Launch (7), Launch2 (8), Speed (9), Distance (10), Duration (11) and again back Zero (12)
  • Now we can zoom in…

  • After making servo zero line visible and zooming we can see detailed servo log. We are talking about V-tail servo nr.4 (JR/Graupner layout)
  • Zero flying phase (2) should be really zero ; BTW I use it for correct setup of all flying phases before each flight especially to compensate temperature servo offsets.
  • Flying phase launch (7) is -1,1% i.e. -1,1*0,21=-0,2mm (sure, I guess maximum tenth of mm has some sense…)
  • Flying phase launch2 (8) is +0,9% i.e. +0,9*0,21=+0,2mm
  • Flying phase speed (9) is -2,5%*0,21=-0,5mm
  • Flying phase distance (10) is -1,8%*0,21=-0,4mm
  • Flying phase duration (11) is +3,4*,21=+0,7mm
  • And again flying phase Zero (12)
  • On log you can also see full servo nr. 4 movement; full down, full up
  • On flying phase Duration (11) you can see servo after full down deflection not coming back to exact same level (13). Hmm, its’s difference about 0,08mm. Let’s think why…
  • …and now you know my Dingo elevator setup for all flying phases, I use also sub-phases but for now let’s keep it simple

Hints for real flying and servo logging:

  • Standalone (not V-tail) elevator servo is valuable record.
  • V-tail is a bit more messy while there is also mixed rudder movement to watched servo.
  • I would say flap servo log is very interesting, but you should be aware when there are elevator-flaps (snap flap) mix or aileron-flap mix, record will be a bit messy. I use for tuning purpose switch which switch-off all mixes to watched servo e.g. when searching the lowest sinking I use very sensitive LOLO vario and then reading what was flap deflection.
  • Sure you can use virtual servo/switch to mark any event during flyight and you don’t have to be limited only to status ON/OFF. You can define for yourself many levels.

Real flight analysis

Now let’s analyze real flight. It was duration F3B task “A” from 150m(300m) line, no wind or about -1m/s i.e. back-wind on launch. Quite nice weather 21-st November 2009, temperature about 10-11°C,  I was logging flap servo nr. 6 on my Dingo.

Let’s look at launch part of light

  • In this case was coefficient to calculate real flap movement in millimeters about 0,48 . As I already said, we had nearly back-wind, this was reason why I stayed at Launch1 (12mm) so long.
  • Launch2 (4mm) before zooming i.e. Speed…
  • …followed by pull (11mm), then I see some unnecessary pulls(?)
  • Switching to Duration

Now we can analyze just flight itself. Using measurement mode cursor (1) we can see that sinking was about -0,28m/s. Flap deflection was about 5-6mm, maybe even less.

Looking at second part of flight we can measure that sinking was about -0,46m/s. You can also note that flap deflection was bigger than in first flight part; about 7-8mm. OK now there is space for discussion. Higher sinking was due air change or flap deflection was already too big (bigger drag)? I remember that weather conditions at mentioned day were very smooth and constant. I have also other records from that day and behavior of Dingo was very similar; I would say 7-8mm on duration is perhaps too much…

BTW that day I was recording more than 12 flights. Duration flight profile was very similar to each other and I found sinking of F3B Dingo about -0,37m/s using wing trailing edge deflection about 5-6mm.

I just showed you one example how LOLO5 can help you to fine tune your airplane.

4 comments to LOLO5 PC software

Leave a Reply

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>