4. My tf_monitor gives me the output as below
Node: /amcl 10.0502 Hz, Average Delay: -0.0153442 Max Delay: 0.145252 <==
which is in negative
Node: /eskorta_odom 22.022 Hz, Average Delay: 0.000921226 Max Delay:
0.0214084
Node: /eskorta_state 30.0514 Hz, Average Delay: 0.0180185 Max Delay:
0.0565425
Is it fine to have negative delay? -  i am not able to figure it out since
this is my pre-hardware testing.

I'm not sure why the average delay would be negative. I'll let someone who knows more chime in on this.