UAV and Heli's

Archive
1

i’m trying to luck up the courage to move up from my coaxial RC chopper to a 450 size heli. Big learning curve i know but worth a shot.
Im also quite taken by the idea of UAV etc. Anyone got any experience with the Ardrones Ardupilot mega 2.5?? looks pretty nice and the ground station software looks great.

Eventually it would be worth a chuckle to try something like a 10 mile distance attempt with 15min flight hops for re batt all way pointed!!!

2

@ HughB - Pfft Ardupilot smardupiolt… i had a Netduino Mini stabalising my plane a year ago :slight_smile:

3

@ Justin - Coool, i didnt think .Netmf was fast enough to that kind o stuff. Its waaaaaay above my coding skill level to even think of attempting something like that (especially with my not yet purchsed Trex 450) on any uC.

4

I half cheated - using this IMU http://store.diydrones.com/ArduIMU_V2_Flat_p/kt-arduimu-20.htm
Netduino Mini reads the serial data from that and does the rest.
FEZPilot 120 is next :slight_smile:

5

Have you looked at something like this?

Was thinking about a FEZ to control this.

6

@ mhectorgato - nah, you want 3 axis accel,gyro,mag and either GPS or pitot for speed connected to fezpilot g120 :wink:

7

oooo sounds nice. Whats the plan for telemetry?. Ive seen some nice Laird 2.4 GHz modules at farewell that have inbuilt temp sensors etc too.

8

Well this would be just for stabilisation - I’m thinking this is moving the PID off of the FEZ. This would allow it to handle the navigation & sensor monitoring.

My thought was Cerbuino XBee combined with a MakeGPS and a few sensors for obstacle avoidance feeding info into this little beauty.

9

@ HughB - Nice module, i was thinking something similar but will have a look at that one as well cheers.

Couple of picks from April 2011

Now every one bangs on about PID loops and yes they maybe necessary for copters but i did a few tests and the below worked a treat stabilizing a 1.6m wingspan foamy…
Code was running on a 48mhz Netduin Mini


        private static void Stabalize()
        {
            bool pitchUp = _pitch > 0;
            bool rollRight = _roll > 0;
            _elevatorServo.Degree = pitchUp ? 90 + ServoAngle(_pitch, 0) : 90 - ServoAngle(_pitch, 0);
            _aileronServo.Degree = rollRight ? 90 + ServoAngle(_roll, 0) : 90 - ServoAngle(_roll, 0);
        }
        private static Int16 ServoAngle(double currentAngle, double desiredAngle)
        {
            double error = Abs(Abs(desiredAngle) - Abs(currentAngle)); if (error < 1) return 0;
            if (error < 2) return 5;
            if (error < 5) return 10;
            if (error < 10) return 30;
            if (error < 20) return 50;
            if (error < 30) return 70;
            return 90;
        }

If anyone is interested i am creating a G120 based modular FEZPilot - main board using a G120 module doing all the stabilization, navigation, logging etc…
It will have a 30pin expansion bus to allow stacking of carrier modules for io and telemetry etc.
Size will be around 60mm x 40mm

10

When I said PID, I was just referring to the stabilisation (kiwi & aussie compliant :slight_smile: ) logic.

  1. Any video of your foamy in flight? If not in flight, any of your stabilisation tests?

  2. I am interested … what’s your ETA? When you say “stacking of carrier modules” … is that akin to shields?

11
  1. Good man dropping the z’s - the G120 will get the pitch roll and yaw and speed from theIMU/AHRS and do all the PID fluff
  2. Some where i have vid, not sure where… i will hook up the AHRS to a G120HDR and a few servo’s in the next week to show how it works.
  3. Depends on Gus and reference designs…as soon as possible…the stacking design is shamelessly borrowed from here https://pixhawk.ethz.ch/px4/modules/px4fmu
12

I’ve wanted to build a quad for a while now. With that other solution it seems to have removed a lot of complexity. There’s been videos of PIDs go bad and copters oscillate wildly. That board has inputs for aileron, elevator, throttle and rudder and 4 (PWM?) outputs for the ESCs. It has 3 separate gyros for each axis/

So from what I gather from that HobbyKing page I would need:

copter “low level” hardware:

  • Frame
  • HK Multi-Rotor Control Board
  • 4 ESC
  • 4 Brushless
  • 4 props
  • batteries

copter “high level” hardware:

  • G120 or CerbBee
  • XBee device (& XBee carrier if G120)
  • MakeGPS
  • additional heading sensors like Accel/mag
  • forward collision avoidance (ultrasonic or IR)
  • ground proximity (ultrasonic or IR)

“base station” hardware (if I don’t use my laptop):

  • XBee device
  • XBee gadgeteer module
  • Spider or G120
  • Display screeen
  • Battery
  • SD module

The only development I would need to do then, would be the base station and the “high level” work.

I’d be interested in your FEZPilot. How would a build out compare if it were based on the G120 FEZPilot.

13

@ mhectorgato - Copters are alot harder than planes…

If i was building one i would make an arducopter from diydrones.com

http://code.google.com/p/arducopter/wiki/ArduCopter

I am using to use of their imu’s http://store.diydrones.com/ArduIMU_V3_p/kt-arduimu-30.htm connected to the FEZPilot for V1.
I would be fairly certain that it would be able to fly a quad…

Your list of parts looks about right.

14

So if I were going to use a FEZPilot, how would that build list change?

15

@ mhectorgato - i’ll ping you an email

16

@ mhectorgato
I’m really interesed in this topic.
I’m fighting now with Parrot AR Drone 2.0 in .NET porting and getting crazy with P264 video stream … but my idea is to make a new one using gadgeteer boards as controller.
I’m now trying to use a Hydra with wifly board for catching tracking data from Parrot using the T35 display.

17

I’m interested too, but have no experience. Perhaps that will change soon … :smiley: