I just completed my Pixhawk equipped 4WD Slash chassis complete with dual GPSs and a 3DR 915MHZ telemetry radio.
The GPSs are mounted at each end of the chassis. The 3DR GPS/Compass module is in the front of the chassis and 3DR uBlox LEA-6 v1.1 is in the rear. Both are protected by the chassis bumpers
The rest of the components are mounted on a navigation platform above the battery.
The rover is powered by a Traxxas 3500 brushless motor and VXL-3s ESC and is using a Spektrum Remote Receiver to communicate with a Spektrum DX8 Transmitter.
I have beefed up the body mounts with extruded aluminum "L" rails to help prevent damage during a rollover.
Unlike my 2WD Slash rover, the battery can be removed for charging without taking the navigation platform off of the chassis.
Here are some pictures of the new rover:
TCIII ArduRover2 Developer
EKF explanation: Kalman Filter
The dual GPS will only work on the Pixhawk. The extra compass in the second GPS would not be used as the Pixhawk has its own built-in compass as well as the external one in the primary GPS/Compass module.
As for the LIDAR-Lite, a library is being written to incorporate it in the Arudpilot code. Testing will occur when I receive my LIDAR-Lite and Tridge has incorporated the library into the ArudRover2 firmware.
There are members who are using both the M8 and the Navspark GPSs. I am waiting for my M8 which should be here in another week, though too late for the AVC. There have been some questions concerning the initialization code for the M8, but that is being worked. Today, while I was testing my Pixhawk equipped 4WD Slash rover with the dual uBlox LEA-6 GPSs, I was able to acquire 13 sats and had an HDOP of 1.2 - 1.3. The M8 will probably get the HDOP down to less than 1.0.
TCIII ArduRover2 Developer
Nice work. But, why do you need dual GPS? Shouldn't one module be sufficient?
Will it be possible to install small fpv camera on it and stream live video to the computer or tablet?
I missed your previous post where you commented about the dual GPS, "The present beta firmware will select the GPS that has the most satellites at any given moment."
I might be missing something here since it doesn't make any sense that one GPS detects more satellites than the other. If one module uses the most satellites and the other doesn't, then one is defective. If they randomly alternate detecting the most satellites, then that means that both can also detect the wrong or correct amount of satellites at the same time.
Anyway, I don't think that throwing more redundant hardware is good solution.
Thanks for the kudos, much appreciated.
For redundancy and for protection against potential dropouts (looses lock) where only one GPS momentarily drops out, but not both.
I have reviewed dual GPS performance using my dataflash logs and there have been instances where one GPS momentarily lost lock while the other one did not loose lock and the rover stayed on course.
But suit yourself. If one GPS is good enough for you then stay with one GPS. I base my findings on emperical testing so that I know that the dual GPS configuration performs as expected.
Yes, you can install a small FPV camera on a rover and live stream the video to a whatever you want.
I have run a GoPro camera on this rover without a transmitter which could be easily added for live streaming.