Re: Pixhawk - Marvelmind
Posted: Sat Jan 07, 2017 5:44 pm
Hendrik wrote:Hi cagiva851,
With Marvelmind dashboard I mapped NESW directions correctly to my testenvironment.
1 beacon, left down, = 0,0 (ID 56)
1 beacon, right down, E (ID 81)
1 beacon, left top N (ID 27)
1 beacon Right top (ID 51)
Starting set of beacons: 81; 56,51,27
Georeferencing in modem Lat. N0.00000, Lon E0.00000
(So on the map of Mission planner and APM planner the copter is somewhere on the ocean near Africa)
So when the hedgehog is going from ID56 to ID27 it is going 0 degrees North
I returned to original Ardupilot, so lost the BCN_ parameters (which I thought were only usefull with Pozyx. I have Pozyx, I like the UWB approach, but accuracy and missing the NMEA protocol stopped that path)
I have COMPASS_AUTODEC set to 0 and COMPASS_DEC set to a value where the direction to North is conform my testenvironment.
My testenvironment at this moment is a room at home. I have a hexacopter of 1 meter and a octocopter of 1.40 meter, so testing autonomous flight indoor is very tricky.
I ordered an extra set from Marvelmind, hoping that extra beacons will increase accuracy and preventing loss off beacons by having more line-off-sights.
My test involves picking a carton with the copter, so placing the mobile beacon underneath is not possible.
Monday I will start testing.
You have a very heavy stuff for indoor!
Check the advises above. Check through them again. For you, Hendrik, the most important, indeed, would be to set the gain properly. Like you described already, I would do the following:
- Put the copter in the starting position of on the table or somewhere and make the motors working on nearly flying power
- Run the oscilloscope and see the noise versus signal. With very high probability, you would have to reduce the gain manually, if you have manual gain set. If you have automatic gain control (AGC), then you are, probably, at the optimal gain already. However, check it still. AGC is tricky. You shall have the threshold clearly above the noise from motors, but below peaks of your signal
- Play with threshold, gain (manual vs. AGC)
- Check signal/noise to all your stationary beacons
- If you fly too close to stationary beacon, that beacon's measurement may be disturbed. Or not - depends on the settings and the level of disturbance
When you set optimal settings, you shall be just fine.
With more beacons you can create more dense maps. This helps a lot:
- Signal to noise ratio increases
- Update rate increases
Use feature submap to build submaps: viewtopic.php?f=2&t=544&p=783&hilit=submap#p783
Keep us posting. We will be happy to assist and help