I guess you never heard about Machine Robo, or more known as Gobots for westerners. It was the the transforming robot toyline from Bandai if i'm not wrong. Transformable robot genre was pretty popular at the 70s-80s in japan, and with the success of Takara with their Diaclone series (which in the end turned into Transformers when marketed on the west), Bandai created a similar toyline named Machine Robo. The similarity in design mostly because majority of the creators was working on both projects I guess. Oh, and I think Gobots became part of Transformers franchise in the 90s when Hasbro bought the western producers of Gobots. For Takahiro Yamada, He was also involved in the mechanical design of Beast Wars if I'm not wrong.
And FYI Takahiro Yamada is also the name of the bassist of Asian Kungfu Generation. xp
Thanks MPE. Google was both helpful and very inconclusive. While I had heard of Gobots, the content of the artbook was all over the place, touching on all sorts of series.
^ Haha, no prob, mate! that was understandable because the contents of this book was more of how to create the robots (in model) rather than explanation about the robots specs and concepts like the usual artbook. To be honest I too am surprised that Yamada also designing some mecha from Gaogaigar. I only know Kunio Okawara as the mechanical designer for Gaogaigar (and the majority from Brave series).