Talk:Car/Kinentic Vehicles Proposal

When this says "use of power cube" does that mean this will be a hydraulic drive vehicle that gets 100mpg? I remember reading that hydraulic transfer is much less efficient than mechanical, how will the loss in efficiency be made up? - Lex Berezhny 13:47, 14 February 2012 (CET)

• I think the best practical efficiency of high quality hydraulic pump/motors is 85%. The efficiency of a hydraulic-drive vehicle can be increased in the following ways:
  • Use hydraulics for pretty much everything; this saves weight. The drive, steering and suspension can all be hydraulic.
  • Build the hydraulic system so it recaptures energy from the suspension and braking activities. FedEx trucks were able to get 85mpg that way.
  • Integrate the largest, strongest hydraulic component (the accumulator) into the frame of the vehicle as a stressed member.
  • As much as possible, use metal tubes instead of rubber hoses.
  • As much as possible, use the highest quality pumps/motors possible.
  • Three wheels instead of four.
  • Aerodynamic body.
• The efficiency discussion is complicated by the fact that the GVCS is supposed to be a system of systems. To a large extent, it is the efficiency of the overall system that is important. The efficiency of any one machine is much less important. Measuring the efficiency of a vehicle as compared to other vehicles is unfair, since there are dramatic efficiency gains in terms of manufacturing and maintenance that are realized by the use of modular components. Additionally, defining the vehicle in such a way that it has no (or very few) commercial equivalents (a 3-wheel 2-seater with 1000 mile range for example) means that it's difficult (if not impossible) to compare the vehicles efficiency to anything else.
• Besides, the ultimate goal is a biomass-fueled vehicle, which means even if it's 100% efficient it's going to have a 30 gallon "tank" (or something outrageous given the low energy density of pellets) just to reach the 300 mile range that's standard for passenger vehicles.
• What I mean is: don't worry abotu the efficiency. There are far more important factors in the design. - Matt_Maier 14FEB2012