Lotus just released a concept based on the Toyota Venza where the goal was to trim the fat, ultimately reducing CO2 emissions. Officially, the project was meant to showcase a "viable mass reduction strategy" on two representative models: a 2017 near-term version and a 2020 long-term version.
Comparing the Lotus Venza versus the off-the-lot Toyota Venza, overall mass was reduced by as much as 38% on the 2020 (minus power train) at only a 3% increase in component costs. The 2017 model's mass reduction was 21%. All this was done using processes and tech that should be available and affordable by 2020.Power train included, the 2020's mass was still decreased by 33%, which the US Department of Energy says should be good for a 23% increase in fuel economy.
The process of lightening the two models seems fairly straightforward: take them apart, catalog the parts, evaluate how to reduce mass, and upon reassembly maintain all the standard features (vision, sight line, comfort, etc.).
Key components of the body-in-white have been reduced from 400+ to 211. While the original Toyota used 100% steel in its construction, Lotus's 2020 Venza uses aluminum (37%), magnesium (30%), composites (21%) and high strength steel (7%). No idea where the remaining 5% went, but it may just be regular steel.
The bumpers remain the same, albeit using an aluminum brace beam versus the a steel one (magnesium proved too expensive).
Any hinged parts (originally, again, 100% steel) and fenders were replaced with parts made up of magnesium (33%), plastic (21%), steel (18%), and aluminum (6%). The remaining 22% is made of "other materials".
Inside, the instrument panel was removed and both driver and passenger have "modules containing all key functional and safety hardware". Both the shifter and parking brake have migrated to the touch-screen interface, and lightweight foam front seats get a futuristic floating treatment by being mounted to the center tunnel and side sill (cutting the need for brackets).
Also, full-floor carpeting gets the ax in favor of removable carpet squares. Lotus says "this reduces mass and allows cost effective upgrading of the carpet quality."
Underneath, all chassis and suspension components have been upgraded to account for the updated mass, keeping this a good exercise in future product development.
By Phil Alex
