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Chassis dynamometer (rolling road)

Saab 96on chassis dynamometer

A chassisdynamometer, sometimes referred to as a rolling road,[4]

measures power delivered to the surface of the "drive roller" by the drive

wheels !he vehicle is often pared on the roller or rollers, which the car

then turns, and the output measured thereby

#odern roller$type chassis dyno systems use the "Salvisberg roller",[%]

which improves traction and repeatability, as compared to the use of

smooth or nurleddrive rollers &hassis dynamometers can be fi'ed or

portable, and can do much more than display ()#, horsepower, and

tor*ue +ith modern electronics and *uic reacting, low inertia dyno

systems, it is now possible to tune to best power and the smoothest runs

in real time

ther types of chassis dynamometers are available that eliminate the

potential for wheel slippage on old style drive rollers, attaching directly

to the vehicle hubs for direct tor*ue measurement from the a'le

#otor vehicle emissionsdevelopment and homologation dynamometer

test systems often integrate emissions sampling, measurement, engine

speed and load control, data ac*uisition, and safety monitoring into a

complete test cell system !hese test systems usually include comple'emissions sampling e*uipment -such as constant volume samplers and

raw e'haust gassample preparation systems. and analy/ers !hese

analy/ers are much more sensitive and much faster than a typical

portable e'haust gas analy/er (esponse times of well under one second

are common, and are re*uired by many transient test cycles 0n retail

https://en.wikipedia.org/wiki/Saab_96https://en.wikipedia.org/wiki/Chassishttps://en.wikipedia.org/wiki/Dynamometer#cite_note-4https://en.wikipedia.org/wiki/Wheelhttps://en.wikipedia.org/wiki/Dynamometer#cite_note-5https://en.wikipedia.org/wiki/Knurlinghttps://en.wikipedia.org/wiki/Motor_vehicle_emissionshttps://en.wikipedia.org/wiki/Exhaust_gashttps://en.wikipedia.org/wiki/Chassishttps://en.wikipedia.org/wiki/Dynamometer#cite_note-4https://en.wikipedia.org/wiki/Wheelhttps://en.wikipedia.org/wiki/Dynamometer#cite_note-5https://en.wikipedia.org/wiki/Knurlinghttps://en.wikipedia.org/wiki/Motor_vehicle_emissionshttps://en.wikipedia.org/wiki/Exhaust_gashttps://en.wikipedia.org/wiki/Saab_96

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settings it is also common to tune the air$fuel ratio using a wideband

o'ygen sensorthat is graphed along with the ()#

0ntegration of the dynamometer control system with automatic

calibration tools for engine system calibration is often found indevelopment test cell systems 0n these systems, the dynamometer load

and engine speed are varied to many engine operating points, while

selected engine management parameters are varied and the results

recorded automatically 1ater analysis of this data may then be used to

generate engine calibration data used by the engine management

software

2ecause of frictional and mechanical losses in the various drivetrain

components, the measured rear wheel brae horsepower is generally 3%$

5 percent less than the brae horsepower measured at the cranshaft or

flywheel on an engine dynamometer[6]

https://en.wikipedia.org/wiki/Oxygen_sensorhttps://en.wikipedia.org/wiki/Dynamometer#cite_note-6https://en.wikipedia.org/wiki/Oxygen_sensorhttps://en.wikipedia.org/wiki/Dynamometer#cite_note-6