VTOL vehicle
« on: December 25, 2016, 08:00:11 pm »
I plan to built a VTOL vehicle that can start as a tricopter and than by rotating of the the motors transform to a fixed wing vehicle.
My question is: Can I have two different vehicle setup simultaneously (tricopter and fixed wing) on cc3d board and switch between them as a switch between flight modes.
Or is it any other possibility to have more than one vehicle setup at same time? Can I have two cc3d boards a switch between them?

Re: VTOL vehicle
« Reply #1 on: January 08, 2017, 10:17:52 am »
Sorry.  Just now saw this post.

You can't have a fixed wing and copter in the same FC.  You could have two FC's if you could find a way to switch from one to the other.

Or there are ways to set it up so that you don't have to change the flight mode.  Take off vertically, pitch over and fly horizontally, all in rate mode.  Hover yaw becomes flight roll.

Re: VTOL vehicle
« Reply #2 on: March 30, 2017, 10:08:21 am »
Sorry.  Just now saw this post.

You can't have a fixed wing and copter in the same FC.  You could have two FC's if you could find a way to switch from one to the other.

Or there are ways to set it up so that you don't have to change the flight mode.  Take off vertically, pitch over and fly horizontally, all in rate mode.  Hover yaw becomes flight roll.

so for these vehicle with only less than 3 motors, under what configuration should we set it as? aero or heli? if it is heli, is it tricopter or quad?

karla

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Re: VTOL vehicle
« Reply #3 on: March 31, 2017, 02:44:03 am »
You can't have a fixed wing and copter in the same FC.  You could have two FC's if you could find a way to switch from one to the other.
Or there are ways to set it up so that you don't have to change the flight mode.  Take off vertically, pitch over and fly horizontally, all in rate mode.  Hover yaw becomes flight roll.


so for these vehicle with only less than 3 motors, under what configuration should we set it as? aero or heli? if it is heli, is it tricopter or quad?

I think a VTOL tilt-rotor vehicle configuration for a fixed wing with 2 motors is possible using Librepilot if using Elevons (not ailerons + rudder).
Should start/hovers like a quad/tricopter and can transition in to fixed wing flight flight and back again.
The configuration would need be Custom (not Multirotor, Fixedwing or Heli), I think.
The Yaw is not used on an Elevon Fixedwing so in Hover mode the yaw is free to control the vertical tilt of the motors (moving in opposite directions to create the yaw motion control).

Ch1 and Ch2: 2 motors, one at each wingtip of the fixed wing
Ch3 and Ch4: 2 servos to control the vertical tilt of the motors
Ch5 and Ch6: 2 servors to control the two Elevons
In total 6 output from the flight controller (Revo board etc only have 6 outputs).

Provided you get the center of gravity aligned over center of lift it should be able to hover with two motors.
The assigning and mixing channels for pitch, yaw, roll is done by the FC and not in the radio transmitter, maybe something like this...
The flight mode switch can have 3 modes to put the vertical servos tilting 1. vertical (hover) 2. 45% (half forward) and 3. 90% (full fixed wing mode).

I have not tried this but I think it could work :)
« Last Edit: March 31, 2017, 05:49:32 am by karla »

Re: VTOL vehicle
« Reply #4 on: April 03, 2017, 10:34:48 am »
You can't have a fixed wing and copter in the same FC.  You could have two FC's if you could find a way to switch from one to the other.
Or there are ways to set it up so that you don't have to change the flight mode.  Take off vertically, pitch over and fly horizontally, all in rate mode.  Hover yaw becomes flight roll.


so for these vehicle with only less than 3 motors, under what configuration should we set it as? aero or heli? if it is heli, is it tricopter or quad?

I think a VTOL tilt-rotor vehicle configuration for a fixed wing with 2 motors is possible using Librepilot if using Elevons (not ailerons + rudder).
Should start/hovers like a quad/tricopter and can transition in to fixed wing flight flight and back again.
The configuration would need be Custom (not Multirotor, Fixedwing or Heli), I think.
The Yaw is not used on an Elevon Fixedwing so in Hover mode the yaw is free to control the vertical tilt of the motors (moving in opposite directions to create the yaw motion control).

Ch1 and Ch2: 2 motors, one at each wingtip of the fixed wing
Ch3 and Ch4: 2 servos to control the vertical tilt of the motors
Ch5 and Ch6: 2 servors to control the two Elevons
In total 6 output from the flight controller (Revo board etc only have 6 outputs).

Provided you get the center of gravity aligned over center of lift it should be able to hover with two motors.
The assigning and mixing channels for pitch, yaw, roll is done by the FC and not in the radio transmitter, maybe something like this...
The flight mode switch can have 3 modes to put the vertical servos tilting 1. vertical (hover) 2. 45% (half forward) and 3. 90% (full fixed wing mode).

I have not tried this but I think it could work :)

how can i calibrate the 2 servos during the transmitter setup for custom configuration and I don't seems to see it during the transmitter setup?

karla

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Re: VTOL vehicle
« Reply #5 on: April 03, 2017, 12:54:24 pm »
... well you actually have 4 servos to set up, not just two.
The transmitter could look something like this ...

Re: VTOL vehicle
« Reply #6 on: April 04, 2017, 03:23:42 am »
... well you actually have 4 servos to set up, not just two.
The transmitter could look something like this ...

4 servos? does it mean that I have to configure a bicopter as a quad with 4 servos?

karla

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Re: VTOL vehicle
« Reply #7 on: April 04, 2017, 04:55:06 am »
Yes 4 servos and 2 motors.

Ch1 and Ch2: 2 motors, one at each wingtip of the fixed wing
Ch3 and Ch4: 2 servos to control the vertical tilt of the motors
Ch5 and Ch6: 2 servors to control the two Elevons
In total 6 output from the flight controller (Revo board etc only have 6 outputs).

This will be a fusion between a fixed wing (with elevons) and a bi copter.
The output configuration can look something like the picture attached.
Try to start to set up the Vehicle Custom window as showed in earlier post.

Re: VTOL vehicle
« Reply #8 on: April 12, 2017, 06:13:03 am »
You can't have a fixed wing and copter in the same FC.  You could have two FC's if you could find a way to switch from one to the other.
Or there are ways to set it up so that you don't have to change the flight mode.  Take off vertically, pitch over and fly horizontally, all in rate mode.  Hover yaw becomes flight roll.


so for these vehicle with only less than 3 motors, under what configuration should we set it as? aero or heli? if it is heli, is it tricopter or quad?

I think a VTOL tilt-rotor vehicle configuration for a fixed wing with 2 motors is possible using Librepilot if using Elevons (not ailerons + rudder).
Should start/hovers like a quad/tricopter and can transition in to fixed wing flight flight and back again.
The configuration would need be Custom (not Multirotor, Fixedwing or Heli), I think.
The Yaw is not used on an Elevon Fixedwing so in Hover mode the yaw is free to control the vertical tilt of the motors (moving in opposite directions to create the yaw motion control).

Ch1 and Ch2: 2 motors, one at each wingtip of the fixed wing
Ch3 and Ch4: 2 servos to control the vertical tilt of the motors
Ch5 and Ch6: 2 servors to control the two Elevons
In total 6 output from the flight controller (Revo board etc only have 6 outputs).

Provided you get the center of gravity aligned over center of lift it should be able to hover with two motors.
The assigning and mixing channels for pitch, yaw, roll is done by the FC and not in the radio transmitter, maybe something like this...
The flight mode switch can have 3 modes to put the vertical servos tilting 1. vertical (hover) 2. 45% (half forward) and 3. 90% (full fixed wing mode).

I have not tried this but I think it could work :)

i tried your configuration to the letter but my bicopter does not seem to take off. i can feel the lift when holding it in my hand but it is definitely not lifting, even at full power.
btw can i use only 2 servos instead just for channel 2 and channel 4?

karla

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Re: VTOL vehicle
« Reply #9 on: April 12, 2017, 07:00:00 am »
Wow, Terrrance, thats really cool you are trying it.

If it does not have enough lift for the weight that will be a problem but maybe its something else. Props mounted up side down, motors spinning correctly clockwise respectively counter clockwise? You have a picture to share of your build?

Can you explain a bit more what you mean about using only 2 servos?

Btw I consider to build and test myself, but I am have little time over after other obligations.

Re: VTOL vehicle
« Reply #10 on: April 12, 2017, 10:00:37 am »
Wow, Terrrance, thats really cool you are trying it.

If it does not have enough lift for the weight that will be a problem but maybe its something else. Props mounted up side down, motors spinning correctly clockwise respectively counter clockwise? You have a picture to share of your build?

Can you explain a bit more what you mean about using only 2 servos?

Btw I consider to build and test myself, but I am have little time over after other obligations.

Hi Karla,

i have tried mounting the pros both way still not lift. currently the downwash are from below (actually I am not sure the direction of the downwash, is it suppose to be below or above the propellers?)
the pros are spinning inwards (based on pics from internet)
weight wise should be around 100g to 200g

right now without any servo, if it can successfully lift will only be flying up and down vertically + tilting sideways. i cannot move forward (no elevator) and cannot move left and right (no rudder/yaw)

saw on the internet that some are using 2 servos to control these two movements, so was hoping to mount something similar as well.


karla

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Re: VTOL vehicle
« Reply #11 on: April 12, 2017, 10:44:34 am »
Cool build Terrrance!

Just looking at the motors and the mass of 200g, I think they are definitely enough to create enough lift :)

Before getting in to details, I think you have two ways to go.
If you want to make 'just' a bi-copter you can do very cool things using the gyroscopic forces described here (f5soh tips)
http://wiki.openpilot.cc/bicopter-hardware-setup.html
I think this set up is extremely elegant and simple.

What I was describing is not that. I can't see how I can combine that with my goal of having a transition in to a fixed wing flight mode (using wonderful LibrePilot). Maybe someone else can.

. Downwash should be felt under, beneath the props in your picture.
. Usually the text engraved on the propellers should be facing front/upwards towards the sky.
. The motors should be spinning in the opposite direction (if left one is CW then the right one must be CCW).
. After deciding the rotation direction of the motors you need to put on the correct prop: they are CW or CCW.

Try some of that?

Re: VTOL vehicle
« Reply #12 on: April 12, 2017, 11:10:06 am »
Cool build Terrrance!

Just looking at the motors and the mass of 200g, I think they are definitely enough to create enough lift :)

Before getting in to details, I think you have two ways to go.
If you want to make 'just' a bi-copter you can do very cool things using the gyroscopic forces described here (f5soh tips)
http://wiki.openpilot.cc/bicopter-hardware-setup.html
I think this set up is extremely elegant and simple.

What I was describing is not that. I can't see how I can combine that with my goal of having a transition in to a fixed wing flight mode (using wonderful LibrePilot). Maybe someone else can.

. Downwash should be felt under, beneath the props in your picture.
. Usually the text engraved on the propellers should be facing front/upwards towards the sky.
. The motors should be spinning in the opposite direction (if left one is CW then the right one must be CCW).
. After deciding the rotation direction of the motors you need to put on the correct prop: they are CW or CCW.

Try some of that?

Tks Karla,

I have the downwash under the pros that for sure. the motor on the left is cw and the right is ccw. the smoother side of my pros are upwards if that is what you mean. the text/specs for the pros are upwards for my case and one of it is label 5x4R which is mounted on the right motor.
what I am not sure is the distance between the pros diameter. based on internet research, the ideal distance should be 3/4 to 1 pros diameter. maybe mine is a bit too short and is causing the downwash to be interfered. some internet pics show a far bigger distance between the pros.

karla

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Re: VTOL vehicle
« Reply #13 on: April 12, 2017, 01:53:13 pm »
I would not worry so much about the distance between motors as if you really have the min and max settings for the ESC calibrated correctly. I suspect your motors might not work at their capacity.
Did you run any setup wizard with LibrePilot on the motors?
You should.
It will save the min and max values directly to the ESC and make them work properly.
Try that...

Re: VTOL vehicle
« Reply #14 on: April 12, 2017, 05:35:48 pm »
I would not worry so much about the distance between motors as if you really have the min and max settings for the ESC calibrated correctly. I suspect your motors might not work at their capacity.
Did you run any setup wizard with LibrePilot on the motors?
You should.
It will save the min and max values directly to the ESC and make them work properly.
Try that...

run the setup a couple of times but still not taking off, moreover now it is turning clockwise now. might have to work on it somemore.