18th annual conference on manual control.pdf - Acgsc.org

visual threshold effects, as well as time delay and neuromuscula_ lag
associated with the human pilot. More importantly, the OCMcan __ used
to predict complex pilot compensation likely to be present in tee control
of high-order dynamics, in contrast to being restricted to only _.ead-lag
compensation. Finally, the objective of the pilot in the tracking task
had to be inferred indirectly in the analysis of Neal and Smith, but is
expressed directly in the objective function of the OCM. Specifically, the
objective function found (from previous research) to be representative of
a pilot's in the task may be expressed as
fT
: (16 (ec - 0)2 + (0c " _) + g(Fs)2)dt
J(Fs) _ o
where (oc - O) is the attitude error, and Fs is the stick force input of
the
pilot.
Admittedl-y, the OCMblock diagram varies drastically from the classical,
single loop structure. However, the OCMmay still be applied to estimate
the pilot's equalization in a compensatory tracking task. To substantiate
this fact, we have used the OCMto estimate spectral densities of the
system's signals (e.g. plant and pilot input and outputs) and then compared
tracking errors from both model structures. Integrating the spe=tral density
over the frequency domain gives the variance of the signals in qJestion by
applying the following relation.
Rx(O ) = _ (m) dm : _X
If the compensatory describing function is accurately estimated via
the OCMwe should obtain comparable error and state variances. And indeed
the estimated compensatory tracking describing function produced tracking
errors within 4% of the OCM. 2_ ]