Autopilot - Rotomotion

[muflonwookie]

Hi,
I started to work with aerial photography and autonomous helicopter almost two years ago. My father and I, wanted to build autonomous UAV for a aerial photography. My father is much better RCheli pilot then me so he was the manual control operator and I was doing research on autopilot. We use Hirobo SST Eagle with Zenoah G260RC engine
We bought Rotomotion Automatic flight control system over one year ago - maybe it was not the only option, but then it looked like the best option. Generally it worked OK, the stabilization was good and it hold the position well. But there were always some problems, and after ca.5 crashes we decided to make an upgrade. (Some crashes were caused by our misteakes and some probably by Rotomotion AFCS unit). We thought that it will be better to invest more money and get a new, better unit.
We send the AFCS and got the new unit back - upgaded and with some extra features. After some problems at the beginning, we managed to achieve autonomous flight again - everything looked perfect until the first crash... we are still not sure why it happened - probably one cable got disconnected and the helicopter got out of control.
And then we had another dangerous situation - in so called "manual mode" the helicopter took the control over and flow away, we found it three days later five kilometers away :-) Right now it is funny for me, but belive me - that days it wasn't.
I am writing this post not to say that Rotomotion AFCS is bad. But I have to admit that cooperation with Rotomotion is not the best - sometimes it is really difficult to get any answer. Maybe we made some mistakes, which caused the AFCS to go wrong - I don't know.
I would like to ask anyone who worked with Rotomotion unit if they can share they experience.
Also if any one use any other autopilot please write how they are doing.
Right now we will switch to manual AP, but for some application (for example photogrammetry project) we need Autopilot.

[Lomcevac]

I have used the Rotomotion product and found the stability and flight control to be excellent. I think that the build quality and robustness of the flight controller hardware is a little poor but the performance is good.
Rotomotion are constantly updating their poducts and hopefully they will move towards more robust components. They are probably pretty busy building UAV's for customers who aren't too bothered how long they last which is probably distracting them from answering your questions. :rolleyes:

Is there a chance that your fly-away was due to your Chan 9 signal putting the autopilot into auto mode or do you thing it was defenitely a fault with the autopilot?

[muflonwookie]

Thank you for response, Lomcevac.

This is exactly what we are thinking too. When it works it works perfect. But sometimes, maybe because of not perfect construction of AFCS something goes bad.

It probably was not the RC Ch9 error, because we did not receive any signals from the Atmega board to linux computer. We only received the GPS position. So there was connection with UBlox but there was no connection with Atmega. It looker like ATmega switched somehow in autonomous mode but without control. And we could not reenter to manual control. Helicopter was really stably, it looked like it was being stabilized. What was strange, was that it was turning around (YAW).

It might have been because of the gas engine interferences. Have you ever noticed that the engine interfere the AFCS? Do you use gasoline engine?

[Lomcevac]

Interesting...

We only used electric power and don't use the system anymore I'm afraid.

[}{ell}{unter]

I think that the best autopilot available in Europe is the Swiss WeControl :

The wePilot1000 is a flight control system for small unmanned helicopters. It consists of an embedded computer system, a GPS receiver, accelerometers and rate gyros for all three axes, a barometer, and an externally connectable magnetometer. The combination of the GPS/Inertial navigation and the robust flight controller design provides attitude stabilization, velocity control for cruise, and position control for hover.

The wePilot1000 allows fully automatic take-off and automatic landing. It has four flight modes:

*

In manual mode the flight control system is bypassed
and the RC receiver directly controls the servos. The
pilot has full manual control over the aircraft.
*

In assisted mode the aircraft is controlled with velocity
commands from a joystick or the RC transmitter. The
pitch/roll stick becomes the forward/ lateral speed
command, the collective/tail stick becomes the
vertical speed/turn rate command.
*

Mission mode allows to fly preprogrammed flight
trajectories based on waypoints in a fully automatic
way. Missions can be interrupted and changed during
flight.
*
In home mode the aircraft interrupts its current
mission and flies back to a predefined home waypoint.

Built-in fault detection mechanisms warn the operator of malfunctions,
and emergency procedures like automatic return to homebase provide
additional levels of safety. A general purpose I/O interface allows control
of custom payload equipment like automatic camera shutter triggering.

The wePilot1000 was specifically designed for advanced small helicopter applications where small size, light weight, low power consumption, and high-performance are essential requirements.

[Connexxion]

@HellHunter:

Do you have any experience with this autopilot?

B'cause I've been looking at it,but the price looked like a barcode :eek:

For the price they're asking that thing should be able to fly a brick!

Connexxion

[Jack Crossfire]

Most buy those for business use, before taxes. That's why they can be so expensive.

wePilot1000: 25,000 Euros

[}{ell}{unter]

@ connection :

Yes, we have experience with the WeControl unit. We use it in our heli (Geocopter.nl) and it can even fly a brick i think. It's amazing. The 25000 € (it's even less) means installed, testflight, ground station and software and all the other connections...
The software of the autopilot can be configured to send a signal where the camera needs to be triggered, how much overlap they need to have, etc.
We mostly use it in auto mode : make a flightplan, press the button and the heli does the rest : take off, waypoint flight, photos taken where needed, landing... Very easy.

[Connexxion]

@ Jack Crossfire:

I knew it was between 25.000 and 35.000 euro,hence the term "Barcode" :D

@ HellHunter:

Thanks for the info.

I found the E-Producties and Miramap before by means of Googgle search. ;)

I've been looking for a europe or asia based autopilot manufacturer for a robust autopilot.Hard to find and if you do,they're asking military budget prices.

A US based manufacturer is a no go,since the US Commerce decided to restrict autopilot exports. :confused: