Appeared on episode 7 of the NHK documentary “Beyond the Century,” on October 15th, 2000. A short description of the robot was added to the honda.co.jp/robot website by November 2000 (first capture by Wayback Machine). At the time the robot was referred to as the “P3-improved prototype” (P3改良型試作機) but was added to the Twin Ring Motegi museum as P4 in 2010. The only other footage is from a PBS’s special called “Beyond Human.” On November 20th, 2000, Asimo was shown off for the first time. At Robodex just a month later, both Asimo and a normal P3 made an apperance. I can only assume that P4 was not shown publicly due to there not being a backup robot in case of failure.

In comparison to P3, P4’s weight is reduced from 130 kg to 80 kg. P4 has two degrees of freedom on the waist which allow it to twist and rotate. There is also an additional degree of freedom on each hand. For comparison, the original Asimo model has only 26 degrees of freedom.

Where Are They Today?

It is presumed that only one P4 was built (before the program became more focused on Asimo). One P4 is on permanent display at Twin Ring Motegi in Japan.