(shown above, the fastest ArduRover yet, an electric go-kart built by Autodesk CEO Carl Bass [shown with author Kevin Kelly] and run at the Self Driving Cars track day this weekend)
From the announcement thread:
Hi everyone. The ArduPilot team has created a new Rover beta. You can download the binary directly here
or if your using a GCS like Mission Planner tick the box to see the Beta downloads available.
If you have any comments or questions please post them in this topic and I'll do my best to answer.
Fixed arming for Skid Steering rovers. You should now be able to arm your skid steering rover using the steering stick. NOTE skid steering Rovers - you will not be able to disarm. The reason for this is zero throttle full left turn is a perfectly valid move for a skid steering rover as it can turn on the spot. You don't want to be executing this and have the rover disarm part way through your turn so I have disabled disarming via the steering stick. You can still disarm from the GCS.
Improved Steering Control:
For historical reason's the steering controller was using the raw GPS data without any filtering. If you have every graphed this data you will see on a rover its very spiky and all over the place. This spiky'ness was feeding directly into our steering controller and causing inaccuracies. Now we using the EKF GPS filtered data which is much smoother and accurate and the steering control has greatly improved.
Previously when corning we didn't take into account any "lean or tilt" in the rover - we assumed the turns were always flat. We have changed this to now take into account any lean so turning should be more accurate. Boat users should really benefit from this too.
EKF2 improvements - its continues to get better and better.
There have been other changes but the above ones are the big ticket items for Rover users.