  Robotic avatar systems promise to bridge distances and reduce the need for
travel. We present the updated NimbRo avatar system, winner of the $5M grand
prize at the international ANA Avatar XPRIZE competition, which required
participants to build intuitive and immersive robotic telepresence systems that
could be operated by briefly trained operators. We describe key improvements
for the finals, compared to the system used in the semifinals: To operate
without a power- and communications tether, we integrated a battery and a
robust redundant wireless communication system. Video and audio data are
compressed using low-latency HEVC and Opus codecs. We propose a new locomotion
control device with tunable resistance force. To increase flexibility, the
robot's upper-body height can be adjusted by the operator. We describe
essential monitoring and robustness tools which enabled the success at the
competition. Finally, we analyze our performance at the competition finals and
discuss lessons learned.
