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Posted by Shikra | Jan 27, 2021 @ 05:59 AM | 31,006 Views
A new approach to bring low cost antenna tracking to standard analogue flight controllers used for iNav and Betaflight without the need for any additional hardware on the aircraft for most flight controllers.
It also supports all other FC’s that use minim hardware with MWOSD 2.0 and also many others with addition of a video telemetry module.

We have been flying with this tracking method for a couple of years as a side project and the design has now evolved to the point of exceeding the performance of other commercial trackers we were using so have decided to release it as a kit for those who are interested and also have access to 3D printing facilities.

Key points:
• Low cost DIY antenna tracker
• No extra hardware required each aircraft
• Does not require bluetooth or wifi modules on RC transmitter
• Simple and reliable tracking
• Ultra-fast position updating – up to 30 hz

Full release GPS enabled flight control systems supported:
• iNav – all max7456 compatible FC running 3.0 onwards
• Ardupilot / PX4 /KISS / MULTIWII and other FC using external minim OSD running MWOSD 2.0
• GPS standalone OSD using MWOSD 2.0 on minim hardware

Other supported systems:
• iNav – earlier versions with modified releases
• Betaflight – versions with modified releases
• All other GPS enabled OSD / FC can be supported with use of micro minim osd acting as a telemetry module

...Continue Reading
Posted by Shikra | Jul 06, 2017 @ 11:23 AM | 19,421 Views
My feedback from testing:

I paid for this plane myself. Took a gamble as one of the early backers.
Have no allegiance or pressure for positive review from FinWing and it is my first plane from them. Consider this unbiased.

  • It’s a great looking and well thought out plane! I am happy with the purchase.
  • The v2 T tail looks awesome and works well.
  • It is VERY quiet.
  • It is a great kit to build. Good access, simple and straightforward. A real bonus is being able to install all gear, motors etc. and carry out testing without tail or wings attached.
  • It folds down.. probably why your reading this - right! Well I found just chunking in the car with the wings detached a huge positive.
  • Nice to launch – good hand width and thoughtfully placed grip areas.
  • Well positioned and thought out mounting for camera options.
  • Gyro stabilisation is well worth adding. It is a small model and this helps.
  • Quite agile – can bank and turn quite well.
  • This will be a regular flier and I would buy from FinWing again.
  • Over 50 minutes total fly time on first battery. Surprising because I wasn’t trying for any duration records.

  • I needed a 4s5200 to achieve balance. Really I would prefer to fly this with 3s 4000 and expected to get balance range from a 3s 3000 upwards. This surprised me – although I have to point out I do not have the weight of a HD camera recording up front which most probably do.

Flying characteristics:
  • Once balanced and set up I found it to
...Continue Reading
Posted by Shikra | Mar 24, 2016 @ 04:12 AM | 32,751 Views
Setting up iNav for Mini Talon V-Tail


Connecting up Naze32 and updating iNAV software

Plug in Naze32

Install Google Chrome

Install Cleanflight configurator from google chrome web store

Launch Cleanflight

Click Firmware Flasher

Download latest recomended version (from

Click Load Firmware (Local) and browse/ select the one downloaded

Click Flash firmware
Posted by Shikra | Feb 05, 2014 @ 08:07 AM | 36,136 Views
Introduction to the MultiWii OSD NG :
  • MultiWii - Supported controller
  • NG - Next generation

MWOSD R1.2 (3 min 35 sec)

Files available here:
Below are some screenshots:
  1. The GUI
  2. Default layout
  3. All options - all items can be turned on / off
  4. Minimal layout from TX switch. Customisable
  5. Radar mode - MAP indicating target home position
  6. MAP mode - MAP indicating position of aircraft related to home. Default view in relation to takeoff direction

Posted by Shikra | Jul 11, 2013 @ 11:33 AM | 29,281 Views

I use this one from 3DR:
The newer OSD's from Hobbyking have different (=better) power circuit than older

Use KV team OSD. Files can be downloaded here:

Not going to re-invent the wheel. Its all here guys!!:
tip: one of most common failures is to forget to power the CAM side of the board when uploading screen fonts. If you get Chinese or weird characters - this is most likely cause.

There are a number of different ways to connect these up. I have attached diagrams for the two most common ways! Especially for 4s guys - but applicable to all other MultiWii boards too.

Option 1 - 12v (most common / typical)
Refer to the "Typical 12v MultiWii installation" diagram
DO NOT bridge any of the solder pads if using this method. Refer to solder pads diagram

Option 2 - 5v
Refer to the "Alternative 5v MultiWii installation" diagram
DO NOT connect 12v to the camera power pin with this connection option
Solder pads as per the "solder pads" diagram

Check the solder pads carefully and that it suits your installation - if you get it wrong there might be nice puff of magic smoke!
Ignore the PAL solder jumper - its not used.

There is also info in the WIKI:

This OSD can by default only read info from the main flight controller. This includes voltage / RSSI etc.
You can mod the OSD to read voltages etc directly. Need to be very proficient at soldering. Info is here:

About OSD variations:
MINIM OSD - Not for MultiWii
MINIM OSD EXTRA - Not for MultiWii
RUSDUINO - Supports older MultiWii and only Rushduino hardware. No longer developed.

This is current:
KV Team OSD. Based on original Rushduino - enhanced, updated and supports 2.2 and greater.
Posted by Shikra | Jun 13, 2013 @ 05:02 AM | 28,233 Views
Collection of FAQ that I receive....

#1 This list!
#2 Setting up RC trims
#3 Setting up MinimOSD for MultiWii
#4 Setting up MultiWii for GPS RTH and HOLD
#5 Setting up YAW
Posted by Shikra | Apr 15, 2013 @ 05:13 PM | 26,022 Views
Two axis Brushless Gimbal for Sony Nex5N

The tilt gimbal arm:

...Continue Reading
Posted by Shikra | Apr 15, 2013 @ 05:08 PM | 26,349 Views
Here is my Single axis design for a GoPo brushless gimbal

And the first video taken with it!

TriiKopta SBGC single axis (3 min 28 sec)

Posted by Shikra | Mar 06, 2013 @ 05:13 AM | 27,333 Views
Shikras GWS multirotor prop balancing guide

If you want good vibe free quality - follow this. You will get better over time. I thought I was good at this a year ago. I now realise I wasn't.
It takes time to achieve perfection. Any one of these points will introduce vibes. A chain is only as good as the weakest link. Same principle.

If this is done correctly:
  • You will not need any anti vibe material
  • You will not have any vibes
  • Your copter will fly better (sensor become more accurate)
It's easy, logical but time consuming.....

Starting point:-

Select good props - known good ones in common use.
Select good motors - if can afford the ones with Jap EZO bearings or NMB even better.
Select good prop adapters

Prep work - start with crap end up with crap.

Check props visually - if they look twisted throw them - or use method below to reshape.

Check prop adapters hole is drilled in the center. If it looks off - throw it away....
Check tightening slots in prop adapter are cut evenly. If not - throw it away...
Check prop nuts hole is in the center some are not...
Check holes in prop nut washers are in the center - again, some are not...
Prop adapters can struggle to stay on shafts - especially anodised ones - So to fix that I hold motor upside down, hold fine emery paper against the shaft and turn it a few times to roughen it up a little. Must not let any of the filings / emery bits get into the bearings. Hold upside down.
On anodised prop adapters it may help to roughen / cut...Continue Reading
Posted by Shikra | Jan 21, 2011 @ 08:03 AM | 186,717 Views
PID tuning theory and configuration guide for MultiWii

Now updated for multiwii >1.9

P is the dominant part of PID and gets you in the ballpark for good flight characteristics.

Basic PID Tuning - on the ground

Set PID to the designers default recommended settings
Hold the MulitiRotor securely and safely in the air
Increase throttle to the hover point where it starts to feel light
Try to lean the MultiRotor down onto each motor axis
You should feel a reaction against your pressure for each axis.
Change P until it is difficult to move against the reaction. Without stabilisation you will feel it allow you to move over a period of time. That is OK
Now try rocking the MultiRotor. Increase P until it starts to oscillate and then reduce a touch.
Rrepeat for Yaw Axis.

Your settings should now be suitable for flight tuning.

Advanced Tuning - understanding impact of P, I and D

P - proportional

P provides a proportional amount of corrective force based upon the angle of error from desired position. The larger the deviation, the larger the corrective force.

A higher P value will create a stronger force to return to desired position.
If the P value is too high, on the return to initial position, it will overshoot and then opposite force is needed to compensate. This creates an oscillating effect until stability is eventually reached or in severe cases, the overshoot becomes amplified and the multirotor becomes completely destabilised.

...Continue Reading
Posted by Shikra | Dec 02, 2010 @ 12:22 PM | 154,852 Views
( !!NOTE - this is still a work in progress!! Please let me know if any errors or have suggestions to improve)

At this point you should have your TriWiiCopter assembled and all connected up correctly as per diagrams. Also the Arduino sketch modified for a TriCopter and uploaded successfully.

I strongly recommend removing your props for the setting up. This should be considered mandatory even if you are not an experienced Tri builder.
You can also use the GUI with the ESC / motors's disabled to visualise instead.

************************************************** ****************

Programming the TX for a TriWiiCopter - Starting point

An Aero model on the tx with default settings. Yes that's right - set this up as an plane and not a heli like gyro based Tri.

1 Set theTx endpoints on yaw/throttle/pitch/roll to +/-125% as a starting point. Others can remain on 100%
- This will almost certainly be needed for the Arduino to recognise correct low throttle / yaw from the tx and hence to enable the throttle control and allow the motors to spin up.
- I would recommend setting expo of +30% on the pitch and roll to start with.

2 Throttle configuration.
- Throttle curve not needed initially
- For much smoother controllability, check out the detail in the Advance Settings for much smoother / more controllable flyiing

************************************************** ****************

Setting up and calibrating the TriWiiiCopter controls

1 Set...Continue Reading
Posted by Shikra | Aug 05, 2010 @ 04:37 AM | 25,874 Views
Component layout in my funjet.
You can see the rx, vtx and GPS embedded in the foam on the underside.
The EZOSD and current sensor are accessible via the hatch on top and are located to the rear of the spar. The ESC is further back next to the motor.

I use a dremel to carve out the foam and make nice smoothcompartment on underside without cutting through and spoiling look above. rx,tx and gps are either velcro'd or foam mounted with some fibre tape for extra smoothing.

Vid tx is slightly proud to allow cooling.

Layout design given to me by Stealthworkx. He perfected the layout.

Battery is nicely placed. A light 2200 3s is about 1/2 inch from the front of the compartment.
Posted by Shikra | Jul 26, 2010 @ 08:19 AM | 36,177 Views
So this question comes up frequently - to use a Head Tracker or not. Jury is out, but a recent survey indicated that most people don't.
I can only say - do what suits you - but give both methods a proper try....

Which type:
There are various methods used - magnetic or gyro based being the most common. Each has its advantages and disadvantages.
I have used both types and I prefer the zero drift of the magnetic ones over the gyro based units - and happy to accept the downside of having to face in one direction.
You might have to try both types to see which suits you.

How it works:
Headtracker connects into the trainer port of a tx that supports advanced features such as setting which channels on the trainer port are passed through to the plane, and which ones are ignored. When the trainer switch is in one position, the headtrackers signals are disabled and the controls on the tx control the pan/tilt on the plane . In the other position, the headtracker controls the 2 channels programmed into the tx

Hardware modification for TX:
I have modified the trainer switch on a Futaba 9c so that it is not spring loaded. To do this, I replaced the existing trainer switch with a replacement "Futaba 2 position long tx switch" available from many sources such as ebay. DO NOT get the sprung loaded version!
This enables you to toggle the headtracker on/off at any time.
Alternatively you can use the cheaper rubber band method if not concerned about turning the...Continue Reading
Posted by Shikra | Jul 16, 2010 @ 05:38 AM | 34,332 Views

Links etc. are being updated. ETA March 1st 2021

A new approach to bring low cost antenna tracking to standard flight controllers used for iNav and Betaflight without the need for any additional hardware on the aircraft.
It also supports all other FC’s that use minim hardware with MWOSD 2.0.

We have been flying with this tracking method for a couple of years as a side project and the design has now evolved to the point of exceeding the performance of other commercial trackers we were using so have decided to release it as a kit for those who are interested and also have access to 3D printing facilities.

Attachment 14571373

Key points:
• Low cost DIY antenna tracker
• No extra hardware required each aircraft
• No extra hardware or modules required for TX
• Simple and reliable tracking
• Ultra-fast position updating – up to 30 hz

Supported GPS enabled flight control systems:
• iNav – all max7456 compatible FC
• Betaflight – all max7456 compatible FC
• Ardupilot / PX4 /KISS / MULTIWII and other FC using external minim OSD running MWOSD
• GPS standalone OSD using MWOSD on minim hardware

• Works with standard FC boards running 7456 OSD IC and running iNav or Betaflight
o FC only requires updated firmware to support tracking
o No additional hardware required
• Does not require Bluetooth / Wifi modules or adapters.
o Not impacted by 2.
...Continue Reading
Posted by Shikra | Jun 17, 2010 @ 04:15 AM | 32,716 Views
Flytron Ultralight Sensor for DragonOSD+


1 - If using a servo lead, note how the white signal and red power leads are reversed to match the DOSD+ board connections.
2 - The original flytron tech sheetl had the Vout / Vin labeled the wrong way round, so make sure download the latest form here:
Posted by Shikra | May 06, 2010 @ 04:47 AM | 36,704 Views
This was the SignGuy thread I read and got the plans from:

Main HobbyKing bits..... (some of these might not be right , but seems to work)

3x #HK-SS30A-HW/6458 Hobbyking SS Series 25-30A ESC (card programmable) variations = $36.92
1x #TR_PC/2169 TURNIGY BESC Programming Card variations = $6.95 (optional)
3x #TP2410-09/5111 TowerPro Brushless Outrunner 2410-09 13A / 104W variations = $25.56
4x #HK401B/10113 Hobby King 401B AVCS Digital Head Lock Gyro  variations = $55.96
1x #HKing-3S/7223 Hobby King Battery Monitor 3S variations = $3.99
1x #GWS-RD-1047/10055 GWS EP Propeller (RD-1047 254x119mm) (6pcs/set) variations = $13.74
1x #TR-UBEC TURNIGY 3A UBEC w/ Noise Reduction = $7.21

I recommend also getting these extras as spares because of HK shipping times. Motor shafts and props get damaged very easily when learning. Seriously!!
1x #HK-SS30A-HW/6458 Hobbyking SS Series 25-30A ESC (card programmable) variations
1x #TP2410-09/5111 TowerPro Brushless Outrunner 2410-09 13A / 104W variations
1x #HK401B/10113 Hobby King 401B AVCS Digital Head Lock Gyro  variations
3x #GWS-RD-1047/10055 GWS EP Propeller (RD-1047 254x119mm) (6pcs/set) variations
1x #TPSHAFT2410/5274 TowerPro Motor Shaft w/ Nut for 2410 Motors (3pack) variations = $4.84

1 * servo - I'm using a 19gr mini
1 * rx - I'm using a corona RP8D1
Deans. 2male, 1 female ( you use others, still get 1 of each for ESC power...Continue Reading
Posted by Shikra | May 05, 2010 @ 05:02 AM | 33,488 Views
What performance changes will I see?

Before mod:
Acquisition time to 5 or more sats - usually several minutes. Sometimes forever!
Max number of sats typically 6
Sometimes drop sats during flight below min count (less than 5).Occasionally drop down to 1 or 2

After mod:
Acquisition time to 5 or more sats - usually less than a minute. Occasionally 2
Never see low sat warning - even in valley or short time inverted flight....
Max sats typically 8 or 9

Caveat!If you are under warranty, this will probably invalidate it.
If you are not confident with fine soldering, get someone else to do it... seriously.
If it goes wrong don't blame me!!

What do I do?
If there is a small strip of foil stuck along the edge of the metal can remove it and clean up residue with a suitable solvent.

Red = warning!
- Be very carefully not to bridge any of the pins when soldering. It is easy to do. Use a desolder pump or wick to remove if you accidentally solder across pins.
- Be very careful if carrying out the amber coloured soldering. Do NOT solder to the thin pcb track running along the outside edge of the GPS module as indicated.

Amber = more difficult soldering. Will see an improvement even without this. - For the soldering on the two outside long edges of the board, this is a little more tricky. you are actually soldering to a very small square PCB sandwiched between the metal can and the main board. Look and understand this first.
- Gently scrape along the...Continue Reading
Posted by Shikra | Apr 13, 2010 @ 05:34 AM | 59,927 Views
Modding the Corona RP8D1 and RP6D1 for the PPM & RSSI output / Long range

WARNING!! - read this first....

This method is based about getting the outputs out onto a plug that a servo extension cable can be made up to suit your particular plane layout. i've also used direct wires - and added and extra set of servo pins too, but have found this method quite neat too.

Ground wire
Depending upon your setup, you may need a ground wire conenction from the rx.
referring to attached photo, solder up as you can see

PPM output - Mikrocopter / DOSD+
Referring to the picture, locate the gold test point that the red wire connects too.
Now quickly "tin" the test point with an iron and some solder.
Now take a servo lead as per the photo and "tin" the end of the red wire ready to solder to the rx.
Place the red wire onto the PPM test point you "tinned" earlier.
Place the Iron onto the joint until it melts. As soon as it solders onto the test point, remove the iron quickly.
Now put some hot glue around the joint.

NOTE: Some instances may require additional resistors and / or capacitors to connect up to the OSD. Depends upon the model. Usuallya 10k in line resistor is a good start.
NOTE: There are apparently now 2 versions of this rx, but even ones I purchased in last few weeks are still the same. PPM output may be in a different location.
NOTE: Test range before...Continue Reading
Posted by Shikra | Mar 26, 2010 @ 03:02 PM | 36,544 Views
OK I built this to try to simulate a hand launch, but hopefully better due to consistency.
10m length 5mm Bungee.
Cariage total length = 2m. Approx 1.5m used for launch
Trigger operate via TX controlling a rx on the launcher
- I have it on ch3 so whan throttle reaches 60% it releases
First test run with full tension of 10lbs. At release this drops to 7lbs.
Tension will go considerably higher. Next Launch might try 15lbs
Safety pin to prevent accidental launch!

The plane holder is removable for different types of planes. Build to the best attach point. For the funjet I used a pusher style - check out the pictures.

Funjet best launch angle is 60 degrees for me.

Making your own? Best tips...
Keep the carriage as light as possible
Build to launch with power on at lower tension

First RC test video:

First FPV launch: