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vcm-le ace measured with the aid ol lour additional bal- conditions, such as atmospheric temperature, atmospheric
dements connected rigidly to the lloating frame with humidity, and air flow around the vehicle body which arc
'me mctmmof measurement is the same as that identical with those encountered during road tests by the
nts oi the resulting aero . nchronized control of the car engine, the dynamometer
dynamic foic.c, that i;, drag, side force, lift, pitching mo- test bench, and the air speed. Rear winds and head winds
... ro • . . deter can also be simulated as required by the control input.
mine La accordance with the 6 deg of freedom from the The control system of the dynamometer test bench has
additional output and input terminals for connection to the
me complete balance can be rotated with infinitely var- computer to enable a iully automatic test program to be
iabl ■. control tarough ± 180 m . g Ch, CT swivelling the base frame carried out.
abom the. vertical axis, ,.o that the test vehicle can be sub MEASUREMENT OF TEMPERATURE AND PRESSURE -I
jceicd to al.\Low from any desired angle to simulate the thermocouples with fixed wiring are provided for measuring tem
influence of a side, wind. peratures on and inside the cars. A row of measuring
Hie measuring rai: • - G oh the balance elements for lift connectors which house sockets for the end plugs of the
a n d d r a ox ' 6 Z" 220 lb) in each case and 300 kp thermocouples --so that the test vehicles needs to be equipped
(ow .o) each lor the side iorce elements. The measuring only with the corresponding thermocouples and connecting
m.-g-.c. oi ea.<m badancc element is in. □ up oi a basic meas- plugs -- are screwed to the floor of the working section.
mmm .mm a e< am m a liiird ol the. total measur-int1 range The connecting leads run to pointer instruments in the con
and two extensions ol th Cr: each one equal to a third trol center through selector switches and the thermoelectric
o. - m . I and which are caused by the automatic intro voltages are fed to the computer, where they are stored,
duction of two sets of weights when the basic measuring converted in accordance with calibration curves, printed,
. oad. Accuracy of ■. . and plotted.
about 10 p (0.35 oz) is not The measuring range of the built-in thermocouples lies
Wfcci of the two sets of w between -40 C (-40 F) and 4-1000C (1832 F). The selected
As in )1 most sliding weig it balai s, the num- mating materials are iron-constantan and nickel-chrome
chanical c< inters, nickel. Additional thermocouples can be installed as re
which cai^bc gaged directly in the appropriate unit of force quired to supplement the 40 thermocouples with fixed wir
(kp or lb) dv the selection a suitable countershaft, is given ing, for example, for measuring temperature distributions
e then gene rated over large areas.
...................I sc fixed concentri Electrical sensors which permit the rapid sampling of
cally on a threaded spindle. The receiver is attached to measured values by means of solenoid step motors arid at
an c.lc.c:rome 1 1 m counter with digital readout. After this, tached pneumatic multiplexers are used for measuring pres
the re.'.ai:, digital vaium; arc led into the computer clcc- sure distributions. A step motor complete with 8 pickups
iroiiicaHv, so that automatic programmed data processing and multiplexers enables 192 different pressures to be. meas
is carried ■ .m m addiiiom'io die recording of measured val* ured pur second. The analogue output vofiagcs arc led io
the computer and processed in the manner described above.
: ■ Y . mmk nmi'/wr JEST BENCH - Apart1 from the six-com PROCESS CONTROL SYSTEM - The complete climatic
pouciit acmdyuamlc balance, tne program-controlled dyna wind tunnel installation can be controlled automatically
mometer- test bciicn(m,.idc by Schenck, GmbH, Darmstadt) is or semi-automatically as required. With semi-automatic
the the most important individual testing unit in the wind
tunnel. With this unit, engine outputs of up to t :■ c PS (118
hp) can be braked and driving outputs can be produced
•with values of up to 85PS (84 hp) to simulate downhill gra-
diems. Tire program control of the dynamometer test bench
malms it possible to simulate vehicle weight, rolling re-
p 1
sisumcc, madient. resistance", air drag, and acceleration re-
si ounce, lac imm' of the executive program can be fed
over • or magnetic tape as required. The difference
between (he inertia oi the vehicle and the test bench can
be automm mm iy compensated so that when conducting test
p.m/mm- me. < e.aiiiious of road nesting can be reproduced
as cxa< .i jh).,:;ibic..
Tim i,.r i s; parameters such as engine specdj engine
torque, th.m:: ...left,-..md road speed arc taken over from
maiccLa—•; magnetic tapes which were recorded under Fig. 5 - View of the control center with process control
actual io.;.. ......ditioir. during road tests. Thus, it has been system IBM 1710/1620
