About lidar and encoder

I’m a fresh here and build a rover with PIXHAWK(CUAV V5+).there are two questions confues me for a long time.
1.when the ArduPilot can support two lidars work togethere?(one for forward and one for backward,so that I can put some eqpments between lidars。such as car gimbal camera or other missionload)

2.why the sliding rover (usually 4 wheels and 4 motors,one motor for one wheel) just support only two encoders?I think it will be more precise if ArduPilot can support 4 encoders(4 wheels,4 motors,4 encoders,one encoder for one motor and one wheel).Because once the rover meet a concavity ground,the wheel without encoder roll on the concavity ground ,one or two wheel may over slippage beacuse of dangling.Without encoder and this wheel is open-loop controled.When the rover keep moving ,this wheel will keep high speed rolling by inertia. When this wheel will re-touch the groundand。It bring a problerom that is the rover will move a wrong short distance or get a wrong degree.All I mean is if supports 4 encoders the rover move as straight line or a standard circle and all the problems will not happen theoretically.
If theres something wrong with my understanding,please tell me.

Sorry for my english,I’m not a English nativer

Thanks all ArduPilot developers.all of you give us a good and simple platform to build the rover

Really don’t know about number #2, never worked with rovers a lot… but regarding your first question, ardupilot supports up to 8 rangefinders at the sime time if I remember well (or something like this). beyond correctly seting up your hardware, you have to be sure that the _ORIENT (orientation) parameter for each lidar is the correct one.

thank you for your support
i’v set a 360 lidar at the front of the rover(about
scan 225° dgress)for avoiding.the hardwares are behind the lidar.when the rover is moving backward,rover might hit something cause not liader scan backward.
the reason that i don’t like to use rangfinder is rangfinder bring some dead area.So 360 lidar is a better chosie for me
and another problem is rangfinder can not work with lidar together.

So what you are saying is that you already have the Lidar360 setup but you had to ignore that “back” sector because you have some hardware obstructing it right? So that’s why you need to place a rangefinder pointing backwards?

It seems that the dev version of rover has PRX1_ and PRX2_ families of parameters, possibly in a near future this kind of setup will be feasible…

Yes your’e right,that’s I mean.
which version is the dev version of rover?the 4.2?
I wish the stabilization version will come soon.
thank you,Bruno

It is 4.4.0 version, it is still dev version but it should go stable in the next months.

Glad to hear that.Maybe I will be the first one to test this new funcation

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