Seems in Japan that Doc Brown used to have his own robot:
Robot #1:
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20050402151335/http://www23.tok2.com/home/usj/ninjya/5-5/doc.htm&usg=ALkJrhgRsxyUS4CQzGrvyXSUn48_BHCGjw
Robot #2:
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20050824120310/http://www23.tok2.com/home/usj/ninjya/etc/doc/doc1.htm&usg=ALkJrhgPeJhIqb6OPhPzwz1-tNM5FK9kiw
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20051104115134/http://www23.tok2.com/home/usj/ninjya/etc/doc2/doc2.htm&usg=ALkJrhjQGl_WFP_eCd2HddQLsjJIOiZ9lQ
Robot #1:
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20050402151335/http://www23.tok2.com/home/usj/ninjya/5-5/doc.htm&usg=ALkJrhgRsxyUS4CQzGrvyXSUn48_BHCGjw
Robot #2:
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20050824120310/http://www23.tok2.com/home/usj/ninjya/etc/doc/doc1.htm&usg=ALkJrhgPeJhIqb6OPhPzwz1-tNM5FK9kiw
https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=ja&tl=en&u=https://web.archive.org/web/20051104115134/http://www23.tok2.com/home/usj/ninjya/etc/doc2/doc2.htm&usg=ALkJrhjQGl_WFP_eCd2HddQLsjJIOiZ9lQ