[faizurrehman]

Hi everyone, i am new at this platform and want to start working on autopilot/autonomous flight path for multicopter. I need a guidance for this purpose. Can you please help me from where and how i start? Thank you

[hwh]

That's a pretty general question.  Without a little more information I don't think anyone will know what to tell you.

You say you're new to this platform, have you worked with other multicopter software?  Do you have a multicopter and if so what is it and what controller is on it?  Almost any more specific information would help us answer your question.

[faizurrehman]

Actually i am new to this field. I came to know about flight controllers like CC3D or Revo etc and searched about them a little. I haven`t worked in this field in past.

[hwh]

Welcome to the forum.  I'd recommend you spend at least a month reading and asking questions on both our and other forums before you consider buying anything.  Learn what your options are and what capabilities you want and which capabilities various hardware and software support.

If you're interested in autonomous flight you need avoid the cc3d controller and buy a revo class one.  The cc3d is based on the STM32F103 processor and lacks the ram to run the gps assisted and autonomous flight modes.  The creative descriptions some eBay sellers and others on the web write make it difficult to tell exactly what some of them are selling so I'd recommend that when you do get ready to buy you post a question with a link to the one you're thinking of buying and ask if it actually is one that supports autonomous flight modes.

[faizurrehman]

I understood well. Can you tell me that is there anything present that i can  do configuaration for autonomous flight or autopilot and instead if testing on real copter can i try it on simulator or something like that.

[TheOtherCliff]

Start by building a quad that can use a GPS.  Twist all high current wire pairs together.  Right now it is not good to use a mini quad because mag sensor on controller is so close to wiring and motors.  Next version we will allow use of cheap GPS/mag so it can be mounted on a pole away from wires.  Use a Revo / RevoNano (Sparky2 soon) flight controller.

Get it built and flying in Attitude mode and get used to flying it that way.

Once it flies well in Attitude mode, add "VelocityRoam" flight mode on your switch and change "GCS -> Configuration -> Attitude -> Settings -> attitude estimation algorithm" from Basic to INS13.  Set Home Location.  Take off in Attitude mode and switch to VelocityRoam.

[faizurrehman]

Now i have pretty much clear idea how to start. Thanx for ur help

[TheOtherCliff]

VelocityRoam mode will let you test out GPS flight with the RC transmitter sticks.  When you get that working well you can set up your first waypoint flight if that is what you want to do.

You need at least two and preferably three flight modes in your switch:  Attitude via e.g. Stabilized1 (VelocityRoam is semi-optional) and PathPlanner.

It is really helpful to have telemetry working and a laptop.

It is fairly simple.  First things are to be aware that you can't trust GPS to be closer than maybe 4 meters to where it should be, so your waypoint flight must have 4 meters clearing on all sides.  4 meters is my tightest safety zone.  I would suggest 10 for a first flight.

Set your quad out in the middle of the flight plan path are with power on.  Let it acquire satellites while you are doing other things.  Use a laptop running GCS and connected to the quad via telemetry.  Go to Configuration -> Attitude -> Settings and click Home Location -> Clear.  That will automatically set Home Location where the quad is, if the GPS has a good lock.

Go to to the Flight Data tab.  Zoom the map in on the area you are at.  Easiest is to right click the map, UAV -> Go To UAV Location then just zoom in.  Right click a point on the map and select Add Waypoint or left click and press Ctrl-A.  Do that for several waypoints but keep them within close visual range for this first time.  Right click on map and select Waypoint Editor.  Change Altitude Above Home to at very least 4 for each waypoint and set Velocity to a reasonable value say 3 (meters per second) for each waypoint.  Some of those settings are tricky sometimes and must be done quickly and on to the next setting or they reset to 0.

When you are happy with the waypoint flight plan, upload it by pressing the green up arrow at the top of the WP editor.

Set to Attitude mode, Arm, take off, hover at say 2-3m high.  Switch to VelocityRoam mode and make sure that is OK.  For the next mode, before you switch to it, plan on switching it back instantly so you will be ready if something goes wrong.  Altitude is the most likely thing.  You may have to play with manually setting Home Location with a click on the map, but be aware that it will ask you for altitiude above Geoid and that is altitude plus (a sometimes negative) GeoidSeparation.  Get your sign correct.  Adding a negative is like subtracting a positive.    You can see what that should be by adding Altitude and GeoidSeparation from System -> Data Objects -> GPSPostionSensor.  Switch to PathPlanner mode and watch it fly the waypoints.  It will start over after the last waypoint.  You have to take it back to some other mode to get it back with this simple flight plan.  Of course take off and landing are configurable in the editor.  I honestly haven't used them with waypoints myself, but others have.

[faizurrehman]

OK that was very clear instructions Thank you for them. For now i am now starting search for equipment/components to buy and to assemble quad copter, things like flight controller batteries main frame etc
. So is there anything you would like to guide me like any recommendations. I would really appreciate that.

[TheOtherCliff]

Well first of all you need to know how to solder.    Without that, you are limited to buying components with matching connectors.

In addition to mags needing twisted wiring, the baro needs to be shielded from all prop blast and wind of motion.  I use an inverted clear plastic parmesan cheese tub.  lid attached to frame with double sided tape.  lid with a hole in the middle for wires to go through.  FC and RC Rx mounted on the lid.  ESC wires up through the hole.  tub put on for flying.  Rx antenna is a small problem.

Understand what failsafe is and be aware that the RC has failsafe and the FC also has failsafe and understand how they are set off.

I always go the cheap route and figure I will get something more expensive if it doesn't work out.  So far I haven't needed to go to the expensive stuff.  When you get it all working, then spend the money on what you want to look good.

Beware of shipping costs when buying and simply consider that as part of the price.  When I quote a price it includes shipping.

These quads are so cheap that I buy several for spare parts.  I have about 3 kits plus one flying, and one made for a friend.  They have a place for a camera and for mounting FPV / telemetry transmitters.  $14 shipped.
http://www.ebay.com/itm/381222779792

Standardize on motor size and KV, prop size, and battery cell count.  They are all interrelated.  I tend to go with lower RPM setups as the sound is not as annoying to neighbors.  Buy a spare while you are buying them.
For motors I use 2212 (size) 900 to 1000 KV (sort by price+shipping, lowest first)
Beware that all these inexpensive motors have short stud prop adapters that barely work with standard 10x4.5 props.
Try to verify (maybe a message to the seller before buying) that they have a knurled prop adapter, some come with no knurling and I use a dremel to cut some simple knurls.
http://www.ebay.com/sch/i.html?_odkw=2212+brushless+%28930%2C+980%29

Many people like these, but they are a bit more expensive at $12.50 each
I recently got some for $9 each
http://www.ebay.com/itm/4pcs-SUNNYSKY-X2212-13-980KV-Outrunner-Brushless-Motor-for-RC-Multi-rotor-Copter-/321882308687

Props that match are 10x4.5 to 4.7 but not 3.8 (all props MUST be balanced before use)
Get two different colors (front/rear)
Buy at very least 2 complete sets
Make sure that the pictures look like the same prop style when you buy different sets, but even different styles of the same size will work reasonably well.
http://www.ebay.com/sch/i.html?_nkw=propeller+cw+ccw+10+%284.5%2C+4.7%29

Lipos are 3 cell (3S) from 2200mah to 4000mah
must be 3S to match the other stuff
don't buy them on ebay unless you buy a name brand
don't buy used lipos
I was lucky enough to find some very nice Venom brand lipos on eBay
Lipos from HobbyKing (e.g. Turnigy) are OK and cheap, just get the cheapest ones (but probably not the B grade).
Beware HobbyKing as they are crooks when it comes to fixing their own mistakes.
There are many good brands of lipos and probably even more bad brands.

ESCs:
Get 20A to 30A ESCs.
Buy them 5 at a time for quads to have a spare.
Know whether you are buying ones with Atmel or SiLabs processors.
You need to research procedure and hardware for flashing ESCs
Get the correct flashing dongle for your processor brand, and big heat shrink tubing to cover them back up.
This is a journey of learning.
I buy ESCs for $4 to $5 from eBay, but I know how to determine the processor and just as important the exact model so I know what firmware to flash.
Use an automotive bulb in series with a flight battery when powering them for the first time after flashing.  If the bulb lights up you did it wrong.  If you don't use this current limited power supply like this, you just smoked an ESC.
If this is too daunting, buy some pre-flashed (SimonK or BLHeli) for about 3x or 4x the price, but that is OK.

[faizurrehman]

yes, i do know soldering and had much experience with digital electronics but as it is my first attempt so i was conscious and you know it never hurts to get advice from someone experienced . Thank you for your recommendations. Now i will do research on these components and buy them for my first quad.   

[faizurrehman]

And as i told you i want to use for autonomous flights so what controller do u recommend?

[TheOtherCliff]

Either Revo or Sparky2.

Sparky2 support will probably come with next release.

There are many clones (Revo and Sparky2) out there.  Some have bad baro data that might be fixable with a simple removal or addition of a capacitor.  Some Revo clones are smaller than stock Revo.  Some small Revo clones don't have telemetry without buying a separate "oplink air".

[faizurrehman]

thank you for your help and precious time. i really appreciate that 

[backyard]

If you are new to quad flying buy one of these "toys" with the extra batteries and charger and spare props and fly/crash it around the yard.  It is surprisingly gentle and easy to fly and very durable.  It has a camera that you can play with as well. 

http://www.banggood.com/Syma-X5C-Explorers-2_4G-4CH-RC-Quadcopter-Mode-2-With-Camera-p-913827.html