This research shows that an existing rear-wheel drive vehicle may be easily retrofitted with a continuously variable-transmission for the purposes of reducing the overall fuel consumption of the automobile. The retrofit-ability of this transmission is the primary advantage that it exhibits over other continuously variable-transmissions. By retrofitting this vehicle with the transmission components that are shown in this paper, the existing vehicle transmission continues to be used with the exception of the driveshaft which is replaced by the hydraulic continuously variable-transmission itself. Using a standard model for the vehicle dynamics, this paper presents a detailed analysis for the speed ratios of all gears, and shows how to specify the size of the hydraulic pump and motor to insure a safe pressure level of operation. To illustrate the usefulness of this method, an actual transmission is designed for the 1997 Ford Ranger, and the range of adjustability for the transmission is evaluated by seeking to hold the engine speed constant for a ramped speed output of the vehicle. In conclusion, this research shows that the design methodology is valid and that only minor errors in engine speed are observed during low ground velocities for the vehicle.

References

References
1.
Singh
,
T.
,
1992
, “
An Investigation into Power Train Enhancements to Improve Automotive Fuel Economy
,” M.S. thesis, Wayne State University, Detroit, MI.
2.
“EPA Hydraulic Hybrid Research
,” retrieved date Jan. 7, 2013, http://www.epa.gov/otaq/technology/research/research-hhvs.htm
3.
Pfiffner
,
R.
,
Guzzdlla
,
L.
, and
Onder
,
C. H.
,
2003
, “
Fuel-Optimal Control of CVT Posertrains
,”
Control Eng. Pract.
,
11
(
3
), pp.
329
336
.10.1016/S0967-0661(02)00219-8
4.
Mapelli
,
F. L.
,
Tarsitano
,
D.
, and
Mauri
,
M.
,
2010
, “
Plug-in Hybrid Electric Vehicle: Modeling, Prototype, Realization, and Inverter Losses Reduction Analysis
,”
IEEE Trans. Ind. Electron.
,
57
(
2
), pp.
598
607
.10.1109/TIE.2009.2029520
5.
Kessels
,
J. T. B. A.
,
Foster
,
D. L.
, and
van den Bosch
,
P. P. J.
,
2009
, “
Integrated Powertrain Control for Hybrid Electric Vehicles With Electric Variable Transmission
,”
IEEE Vehicle Power and Propulsion Conference
,
Dearborn, MI,
pp.
376
381
.
6.
Ehsani
,
M.
,
Gao
,
Y.
,
Gay
,
S. E.
, and
Emadi
,
A.
,
2005
,
Modern Electric, Hybrid Electric, and Fuel Cell Vehicles
,
CRC Press LLC
,
Boca Raton, FL
.
7.
Kumar
,
R.
, and
Ivantysynova
,
M.
,
2011
, “
An Instantaneous Optimization Based Power Management Strategy to Reduce Fuel Consumption in Hydraulic Hybrids
,”
Int. J. Fluid Power
,
12
, pp.
15
25
.
8.
Dirck
,
M. E.
,
2003
, “
The Evaluation and Analysis of a Power Split Hydraulic Hybrid Drivetrain
,” M.S. thesis, University of Missouri, Columbia, MO.
9.
Vermillion
,
S. D.
,
2011
, “
Modeling a Hydraulic Hybrid Drivetrain: Efficiency Considerations
,” M.S. thesis, University of Missouri, Columbia, MO.
10.
Al-Ghrairi
,
T. S.
,
2012
, “
Designing and Modeling a Split Torque Hydrostatic Transmission in Series With a Manual Transmission for an Automotive Application
,” M.S. thesis, University of Missouri, Columbia, MO.
11.
Manring
,
N. D.
,
2005
,
Hydraulic Control Systems
,
John Wiley & Sons
,
New York
.
You do not currently have access to this content.