Increase collision tolerance by increasing KE height

[iche033]

addresses #967

The KE height is now increased to a number that allows all wheeled robots to go over the hallway in the urban tile without suffering from collisions.

For testing,

1. comment out this line so you can teleport the robot without the collision detector triggering then rebuild subt.

2. launch sim with finals_practice_02 world:

   ign launch -v 4 competition.ign worldName:=finals_practice_02 circuit:=finals robotName1:=X1 robotConfig1:=CSIRO_DATA61_DTR_SENSOR_CONFIG_1
   

3. Move the robot to a few meters before the hallway:

   IGN_TRANSPORT_TOPIC_STATISTICS=1 ign service -s /world/finals_practice_02/set_pose --reqtype ignition.msgs.Pose --reptype ignition.msgs.Boolean --timeout 300 --req 'name: "X1", position: {x:11.2 y:-47 z: 0.818} orientation: {x:0 y:0 z:-0.7068252 w: 0.7068252 }'
   

4. Send vel cmds:

   rostopic pub  /X1/cmd_vel geometry_msgs/Twist -- '[3.0, 0.0, 0.0]' '[0.0, 0.0, 0.0]'
   

5. Monitor the events.yml log for collisions when the robot moves forward. Note you should see one collision entry due to robot falling to the ground after it was teleported.

   tail -f /tmp/ign/logs/events.yml
   

With the changes in this PR, you should not see any more collisions in the events.yml log file as the robot drives over the hallway threshold.

[acschang]

LGTM. I was not able to trigger the collision over the tile connections with CORO ALLIE, CSIRO DTR, or CORO ROCKY. I also tried Explorer R3 (randomly selected) and there did not seem to be any adverse collisions for this vehicle either.