Lqr planner max speed being restrained

I encountered problem that navigation control commander doesn’t want to send maximum allowed speed even if space is huge and distance between robot and goal are pretty far…

I’m using Omniverse sim, but due to it looks more like sdk problem - i started topic here.

So i wanted robot to move at speed 4 meters per second.

In Isaac SDK 2020.1 (isaac-sdk-20200527-0159e2bab) i made changes in navigation.control.lqr and set max_speed to 4. Same changes i applied to max speed in DifferentialWheelBase_REB of Omniverse.

Result was that commanded speed was near 2 at top, but usually it was floating near ~1.5

I tried new SDK 2020.2 (isaac-sdk-20201201-427971df2) it required also tweaking lqr_state_cost LimitRange, but still it was hitting top like 2.5 ( upon start of heading to new goal ) and then it was near 2.

What else constraints planner speed?

There may be a couple of factors that could limit linear speed:

  1. max_speed param in DifferentialBaseLqrPlanner (default is 0.75),
  2. RangeCheckLinearSpeed under trajectory_validation which is set in differential_base_control.subgraph.json as 1.5 with an ApplicabilityCheck threshold of 1.0 (which is where we may be topping out at 2.5 in 2020.2).

@Ben_B, anything else that could clamp commanded speed?