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The Nick Axis is very jittering because of the servo. A servo with a higher resolution or a gear (for example 3:1) would be a solution to reduce the “shaking” effect.

But no “wobbling” or “rolling shutter” effect

No filter applied to the material. Check it out (available in 720p on Youtube HD):

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This week Holger wrote a request in the Mikrokopter forum for a tool to calculate the flight time of a Mikrokopter based on basic parameters:

• Thrust curve of a Motor (grams over current)
• Number of Motors
• Mikrokopter Weight without Lipo
• Lipo Weight
• Lipo Capacity
• Payload
• Losses
• LipoFactor (g per mAh – typical 50-100 g/Ah) – Here is also a nice List from Nabazul from the MK-Forum

With this data it is possible to calculate the flight time.

Also I created very interesting plots of flight time over Lipo capacity and flight time over payload. (It would also be possible to creat a 3D plot with both parameters)

I decided to make the calculation with a little Matlab script (M-File) that you can download here.

Here are some plots with the following settings (these settings are not very realistic, sorry – they are only choosen to test the skript):

• Motors = 4
• MKWeightWithoutLipo = 500g
• LipoWeight = 800g
• LipoCapacity = 2500
• Payload = 100;
• Losses = 0.1;

Thrust Characteristic (source: http://www.mikrokopter.de/ucwiki/FlugZeit)

• Roxxy2827-35
• 10” EPP
• 4s Lipo

Polynomial (3rd grade) fit of the measurement points.

Flight Time over payload calculated out of the thrust characteristic curve.

And the most interesting plot is the plot of the flight time over capacity of the lipo battery. Here also the weight of the MK changes with the capacity of the lipo. This is done by the LipoFactor which is calculated by LipoWeight / LipoCapacity * 1000 (about 320 g/Ah in this example)

As you can see there is an optimum at about 3500 mAh for this setup. After that it does not make sense to take a lipo with a higher capacity (assumption: the LipoFactor is constant over capacity).

If you want to play around with your data, you can download the Skript here and have fun and leave a comment if you like it

Speedy

So I mounted the JETI Box on my Transmitter and here are some pictures:

This is the JETI Box Mini:

Now I had to find a nice place where I can mount the Box to the MX16s. I decided to place the Box directly in the middle of the transmitter.

Then I put the signal wires of the JETI Box through the hole

After that I mounted the servo plug to connect the box to the transmitter.

So, the electrical part is done. Now the Box has to be mounted on the transmitter and for that I used sugru – Hacking things better. (Details to that very cool new material can be found here)

And now the final test if everything is function properly.

Next week I will post how the JETI System works together with the Mikrokopter.

Update 17.08.2010: Don’t underestimate sugru – You are able to lift the transmitter only by touching the JETI Box Mini.

Happy Hacking

At the same time I had to think about 2.4 GHz remote control – But I would like to have the choice between the two frequency bands (35 MHz and 2.4 GHz) so I modified the MX16s 35 MHz remote control with the JETI System to have the ability to switch between 2.4 GHz and 35 MHz at any time.

So I can use 35 MHz for FPV flights and 2.4 GHz for “normal” training or fun flying. (Maybe I will buy a 5.8 GHz video set in future, but that is not a requirement in the moment.)

Below you can find step-by-step pictures of the modification of the MX16s remote control.

Good luck with your modification and happy flying

Sender

Als Fernsteuerung ist die MX16s (35MHz Band) von Graupner im Einsatz, welche später auch noch mit dem Jeti System auf 2,4 GHz umgerüstet werden könnte. Zu beachten ist, daß der Senderakku das erste Mal mit 150 mA über einen Zeitraum von 12 Stunden geladen wird. Um den Sender mit dem Mikrokopter verwenden zu können muss noch auf dem Linken Stick die Feder ausgehängt bzw. montiert werden, damit der Stick nicht selbstständig zurück in die “0-Stellung” gelenkt wird. (Es gibt ja kein Negativ Gas/Pitch beim Mikrokopter, also ist der Stick ganz unten auch Gas Null)

Ladegerät

Als Ladegerät ist das ULTRAMAT 14 plus von Graupner in Verwendung welches mit jeglichen Akkutypen zurecht kommt. (Senderakku: NiMH, Flugakku LiPo)

AXI Motoren

Der erste Schritt war die Montage der Motoren. Dazu wurden die LED, Motor und Buzzer Kabel in die jeweiligen Ausleger eingezogen.

Kamerahalterung HiSight II

Zur Erholung nach dem Kabelwirrwarr und hin- und herquetschen der Kabel wurde die Kamerahalterung HiSight II mit Nick- und Rollkompensation zusammengebaut und geklebt.

Montage der Ausleger, FlightCtrl, BlCtrl

Ein weiterer Schritt war die Montage der Ausleger und das sortieren der verschiedensten Anschlusskabel.

Als nächstes wurde die FlightCtrl ME vervollständigt

Montage der BlCtrl an die Verteilerplatine

Montage der Verteilerplatine sowie der FlightCtrl an die Rahmenkonstruktion

Nach dem Anlöten der Motor, LED und Buzzer-Kabel an die Elektronik wurde dann noch die NaviCtrl sowie das GPS montiert.

Anschließend ging es ans lackieren der Abdeckhaube, dremeln der Ausnehmungen der Haube und bohren der Befestigungslöcher – fertig ist der HEXA

Natürlich wurde dieser Mikrokopter auch für die kommerzielle Nutzung für Luftbilder und Videos von HiSystems bzw. Holger und Ingo vom Mikrokopter Shop lizenziert.

Nice Video (+ editing) from Nebukad (location: Lichtwiese).

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Update! – Another really cool flight of Tensor

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Also enjoy the Mikrokopter group on Vimeo.

In January an article on Hacked Gadgets showed a Mikrokopter from Nicoleto.
After visiting his homepage I saw a really nice concept for the HD camera mount.

There are a lot of photos and one video of the construction and the Mikrokopter in action available.

Video (construction, flying, on-board camera)

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So I ordered some evaluation boards (about 100€/pcs) for me and two collegues who are studying with me at the NTB. Our goal is to have fun with wireless applications.

The RN-131 GSX Module is a 802.11 b/g wireless LAN Module with a lot of features – Details see datasheet.

If you already have a GSX Module you can use my LabView source below to show the UDP packets which the module sends in default configuration every 7 seconds.

The packets include

• MAC address of AP
• WiFi-Channel
• RSSI (quality)
• local TCP port
• RTC (real time clock value)
• NTC temperature option (if temperature sensor connected to module – otherwise sensor 7)
• Spare sensor reading
• ASCII time
• Version string with date code and Device ID string

This information can be used to open a TCP connection to the module or to configure it over WiFi. The module has to be in the same subnet as your PC or MAC if you want to receive the packages.

Here are some pictures of the Module in action:

Here is the LabView (8.6) Source as LLB: wifly-monitoring-distribution

I attended the 3rd outdoorflying in Zürich and it was a lot of fun. Of course I had my digital video camera with me and now you can watch the whole day in a short 9 minute clip. Of course there are some scenes with the EPI-OSD hardware with the new C-OSD software from Cascade. A short clip with EPI-S (current measurement) is also included. It was really fun to meet some guys from the forum and to have “real” talks. And of course we had some sausages over the fire (The fire was heated by Mikrokopter(s))

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To improve my Kopter for this event I finally found the time to mount the PET “Haube” onto the Kopter. Pictures will follow in the next days.