You’re ten minutes away from us! I’m Chris@3dr.com
I just ordered the MM system. I’ll let you know how it works. I’m actually sorta hoping to discover how to bypass the Pixhawk/MP system since my robot will be operating in a defined space rather than on the street or other GPS-able area.
PS I just got an email from the Marvelmind customer support with regards to this post…
Yes, I have seen the post. You see, the issue is rather in ArduRover or ArduRover/Marvelmind than in PixHawk. We do have good connection with PixHawk. But there may be some settings in ArduRover different from ArduPilot that causes the difference. Since we don’t actively test with ArduPilot, it is not easy for us to comment. I hope that somebody on the forum may help
I echo that hope
OK… following zlite’s recommendations on the MM forum, I’ve got the MM working with the Pixhawk. In addition I’ve switched over to K3 from K2 and it also seems to work.
The MM system is pretty nice. With battery operated beacons and a nice “dashboard” that I’ve just started to explore, it does the job!
Support is not too slow and they seem to want to continue to make their system better. MM support says that MM beacons with IP67 is within weeks of being available.
So right now Marvelmind is my choice over POZYX for precision localization.
Thanks for the feedback. I don’t have an MM system but I would like to get a wiki page created to help people with the setup… perhaps I’ll make a skeleton page and then others can help fill in the details?
Happy to help. BTW it was @Chris_Anderson*** who introduced the Marvelmind (MM) system to me. The MM people do have some instructions for interfacing with, among others, a Pixhawk copter on https://marvelmind.com/download/. But by their own admission, they do not have much experience with Pixhawk rovers.
***Yesterday we played around with his MM system while at a Hack-a-robot meetup in Oakland. 100 or more folks of all ages with very cool rovers that use vision only for guidance raced each other on a taped-up-track inside the old American Steel building.
Good stuff. I’ll ping here again when the skeleton page is created.
By the way, i personally prefer if we use the software name, “ArduPilot Rover” over “Pixhawk Rover”. ArduPilot runs on tons of different flight controllers including those listed here.
I just found a bug in the latest code, sorry for that
So please follow these instructions:
- Use ArduRover or ArduCopter from master.
- compile it and download the FW to the vehicle.
- set EK2_USE = 0
- set EK3_USE = 1 (use
- set EK3_ALT_SOURCE = 3 (Beacon)
- set EK3_GPS_TYPE = 2 (2D position only)
- set SERIAL3_PROTOCOL = 13 (Beacon instead of GPS)
- set BCN_TYPE = 2 (Marvelmind)
- Use Marvelmind FW >= 5.77
- Set “Raw distances data” parameter to
enabledin the marvelmind GUI dashboard.
A couple of suggestions
set EK3_GPS_TYPE to 2. I don’t know why, but my navigation got a whole lot better than when it was set to 1.
use the MM Submask X&Y shift to get your rover to matchup with its actual position on the MP.
Amilcar, can you let us know when this fix is available pre-compiled in the beta firmware list in MP?
These fixes will be available on ArduCopter 3.6.0
Great. And which version of ArduRover?
ArduRover 3.3.0 … not planned yet
Not 3.2.3? Bummer. All the documentation that says to use EKF3 is now wrong, since it doesn’t work anymore. We can work around with EKF2, but we’re stuck in a undocumented state now.
I’ve just created a skeleton marvelmind wiki page. I don’t have the system so any help people can give fixing it up would be greatly appreciated. I suspect @amilcarlucas will have the most to contribute to this page but there is also a guide-to-updating-the-wiki here in case anyone else wants to get involved.
Thanks, Randy! Great to be working with you again on cars. ROS is overkill for this and ArduRover is very solid – just a few more tweaks like this and it will be perfect.
With DIYRobocars we use OpenCV and 2D LIDAR for the main navigation functions on Rpi, and the interesting question is whether we should use Pixhawk as just another sensor (IMU and GPS) and fuse the data on RPI, or do the opposite (use CV and LIDAR) as sensors and fuse it in ArduRover.
Thanks @rmackay9 that is a very good starting page !!!
Basic question: Is the Ardupilot-Pixhawk-Mission Planner system capable of receiving, controlling and displaying the path of a rover within the same accuracy as the Marvelmind system?
In terms of estimating it’s position, I think AP should be as accurate as Marvelmind because it’s using the Marvelmind sensor data and combining it with the accelerometers. MP should be able to display the position on the Map pretty accurately as well. It’s limited to 1cm of accuracy - I’m not sure if the Marvelmind has better than that …
Re control (which the marvelmind doesn’t do), it’s hard to get 1cm level accuracy in control - i.e. to make a rover be within 1cm of a specified location. I’ve never measured AP’s accuracy and it depends a lot upon the tuning of the vehicle. It’s theoretically possible to get down to 1cm of accuracy but the vehicle would need to be perfectly setup and tuned.
That info is very helpful. I’ve been having issues getting my rover to track to each WP correctly. Now I know its just me.
Well, Rover is not quite bug free yet and tuning is still a little harder than it should be… I hope to release a beta of 3.3 within the next few weeks which will improve the pivot turns.