Update EK3_SRC_OPTIONS description needed

[lida2003]

I have a question about this parameter "FuseAllVelocities"

If EK3_SRC_OPTIONS is enabled, what copter will do?
a) GPS valid, optical flow sensor invalid ==> using GPS only
b) GPS invalid, optical flow sensor invalid ==> ???? any links?
c) GPS invalid, optical flow sensor valid ==> using optical flow only

• Mission Planner, it seems OK
  

• Ardupilot wiki - parameter list // it needs more description about set to "1"
  

• Ardupilot wiki - optical flow sensor // can it set to "1" any further issues, or advanced usage?
  

[rmackay9]

Hi @lida2003,

If the FuseAllVelocities option is set, velocities from all 3 sources will be used regardless of which is active. So for example, if EK3_SRC1_VELXY = GPS, EK3_SRC2_VELXY = OptFlow, EK3_SRC2_VELXY = None, then both optical flow and GPS velocities will be used.

If the option is unset then only the active source's velocities will be used. So if the active source is "1" (e.g. EK3_SRC1_xx) then only the GPS velocities would be used and the optical flow won't be.