This footage was recorded on Nov 29, 2007 at a Hybrid event held by Toyota Sunnyvale in Sunnyvale, CA, USA.

It uses a planetary gear to divert power. Power can come from the internal combustion engine (ICE = blue handle) or the Motor Generator 1 (MG1 = yellow disc) and Motor Generator 2 (orangle handle). MG2 drives the wheels directly (represented by cranking the orange handle before the reduction gears) or the momentum of the car pushes the wheel to spin MG2 to recapture energy during braking (represented by cranking the black handle after the reduction gears). MG1 (yellow disc) can spin the planetary gear (green) while the wheels (black) and MG2 (orange) are stationary, which in turn spin the ICE (blue) before gasoline is injected to the ICE. That pre-spinning of the ICE to operating RPM allows the ICE to be started and shut off at will with reduced air pollution concern (represented by cranking the blue handle, it should only turn in one direction, the model is flawed). MG1 (yellow) can spin backward or forward to redirect power to the wheels (this model does not have a crank handle for the yellow disc, a model flaw again because MG1 must be spun actively to control the output of the HSD).

Visit http://www.wind.sannet.ne.jp/m_matsu/prius/ThsSimu/index_i18n.html to play with a simulator.

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