V-Bar Setup Guide.
Disclaimer: This is a work in progress and draws on my experiences using the v-bar unit. I am not an expert and I am in no way affiliated with Mikado. As my experience, understanding and knowledge of the system increases this document will change. Please read in conjunction with the v-bar manual and other v-bar material. If you are unsure of anything please seek advice. A list of useful resources is provided in my Runryder Gallery.
Part I of the v-bar setup article by Fergus Moloney.
As with any work being carried out on RC helicopters please also follow the manufactures safety recommendations. If using a flight pack and BEC to do the setup then please unplug your motor or disengage the pinion from the main gear. Although no throttle adjustments need to be made with this setup it is still best practice.
Firstly here is a list of items which will help enormously with the setup process.
A Digital Pitch Gauge.
A Swashplate levelling tool:
– Depending on your model many of the basic settings can be edited with either the ‘Start Setup’ button or the ‘Expert Setup’ button and its associated tabs shown below.
Basic Setup:
This is a quick run through the basic setup. This can be used to get any of the models which have been catered for by Mikado in the preset model lists up and running. You will likely have to enter the expert setup to tweak the performance of your helicopter once this basic setup is done. In the meantime this should get you flying.
–Wiring of your servos should be completed as per your swashplate type. Refer to the Swash Typeillustrations in the v-bar manual and connect the servos to the v-bar unit as per the illustrations shown. (i.e. servo no 1, 2 and 3 to right, left Aileron and Pitch)
–Connect the v-bar to the receiver output based on your receiver type. Again this is illustrated in the v-bar manual.
–Secure your v-bar sensor using the supplied tape and an appropriate location ensuring it is parallel with the longitudinal axis of the helicopter. The wire can protrude towards the nose or tail of the helicopter.
–Configure your radio for single servo non eCCPM output. Centre your trims and remove any mixing. Set pitch curves from -100 to +100 with 0 at centre.
–Power up your radio transmitter, receiver and connect the v-bar USB in that order. ONLYThen should you start the v-bar software on your computer.
[This means the v-bar settings currently loaded in the v-bar are displayed in the software program. If the V-bar software is opened prior to connecting the v-bar unit then the settings currently displayed in the software will be written to the v-bar unit once it is connected. This is important to note if you have more than one v-bar unit or multiple v-bar equipped helicopters].
Step1 - Click on start setup, then load the preset of your model type if it is supported.
Step 2 – Check the direction of your channel signals on the Tx calibration panal. Reverse as necessary in the Tx. Then check that mid sticks give zero output (adjust the sub-trim of appropriate channel in your Tx to achieve this) Also check sticks at extreme travel (adjust the endpoint of appropriate channel in your Tx as necessary to achieve 100%). Ignore your servo and resultant swashplate movement at this stage. Disconnect ball links to avoid over stressing your servos if necessary.
Another method can be used by entering expert setup which measures actual signal output rather than a % value. I will cover this in a later document. If you want to use Live view for this step then look for values of 1600 at the extreme stick positions.
NOTE: You are now in adjustment mode so Tx stick movement has no effect on your servos. You can use the sliders on the right of the screen to check swashplate and tail movement.
Step3 – Use the drop down menu to select your preferred servo type. Check your tail servo direction and reverse in the v-bar software if necessary. Now adjust your linkages and/or servo arm to achieve values of between 50 and 60 in both directions. Both values for clockwise and anticlockwise should be close if not the same.
NOTE: Values of 64 and sometimes lower on side A have been found to cause some servos to lose power. You can check this by driving your servo to the extreme with the software and checking it holds with your finger.
Step4 – Reverse Aileron, Elevator and Pitch in the v-bar software as necessary to achieve correct swashplate movement. Test it by using Manual Control sliders on the right of the screen.
Note: If you have set step2 correctly the Tx controlled swashplate movement should also now be correct. You can test this when you finish setup below.
Step 5 – Now use the trim tabs in the software (or better still mechanical adjustment) to achieve a level swashplate and zero degrees at mid stick. Also check trim and pitch at high and low stick.
Step6 – Set your mechanical Cyclic travel limit and ensure you have full deflection without any binding. This is setting your mechanical limit but does not affect rotational rate directly as it would in a flybared helicopter so set it as close to the limit as you can get.
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That’s the basic setup covered
Now use the sliders to set how responsive you want your model to fly and also set your collective pitch range. Cyclic and Tail rates of 70are a good starting point for the first flight.
Check for correct gyro response by tilting the helicopter and observing the swashplate movement. For the Mikado Heli’s I have found the default gain settings do not need to be adjusted prior to the initial flight. The v-bar will now be in Classic mode and will behave in a similar way to a flybared helicopter in the hover.
Now is the time to return to your radio programming and add expo around centre. Start with about 20% then later fine tune to your own liking. Also set your pitch curves in the radio to achieve the collective response you prefer.
The next article involves entering the ‘expert Setup’ tabs and in order to try and keep things simple is being provided separately.
Fergus Moloney