From how I understood it the manual says that the robots must stay inside the bumper area i.e. not cross the bumpers yet in the video and in other places of the manual you can cross the bumpers. Can someone explain this a little better?
Rule <G30> explains the ways in which you can legally cross your bumpers.
<G30> ROBOT Volume – During a MATCH, no part of the ROBOT shall extend outside the vertical projection of the FRAME PERIMETER, except as follows:
a. BALL Interaction Volume – Solely for the purposes of interacting with a BALL, MECHANISMS that are below the BUMPER ZONE may extend up to the BUMPER PERIMETER, for a period not exceeding two seconds. After returning inside the FRAMER PERIMETER, such MECHANISMS are not permitted to re-extend beyond the FRAME PERIMETER for at least two seconds.
b. ROBOT Righting Volume - ROBOTS attempting to right themselves or their ALLIANCE partners may expand up to the FINALE CONFIGURATION maximum volume while, and only while, performing the righting operation. While beyond the NORMAL CONFIGURATION volume and righting, ROBOTS may not actively interact with BALLS or opponent ROBOTS.
c. TOWER Contact ROBOT Volume - During a MATCH, ROBOTS in contact with their ALLIANCE TOWER may extend beyond their NORMAL CONFIGURATION volume but may not exceed the FINALE CONFIGURATION maximum volume.
d. FINALE ROBOT Volume - During the FINALE, ROBOTS may extend up to the limits of the FINALE CONFIGURATION maximum volume.
e. BUMPERS may extend outside the FRAME PERIMETER, within the constraints defined in Rule <R07>.
Violation: PENALTY and YELLOW CARD.
Eek by bumpers i meant the bumps in the field 
Oh, the bumps!
You can’t carry your robot over them (Yellow Card), according to <T15>. Robots are not prohibited from moving over them by anything in Section 7.