曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
V3 was reduced, which alone might contribute to an
increased phase margin; however, V4 had a low crossover
frequency, but not an accompanying phase-margin peak.
With the unknown details of the pilot feedbacks, the V3
configuration must be coupling in with the vehicle
dynamics in a manner different from that in the other
configurations.
The overall disturbance-rejection results suggest three
points. First, the speed at which the disturbance is rejected
is affected primarily by the high-pass motion filter’s
natural frequency. Second, motion-filter gain appears to
affect the relative damping of the disturbance-rejection
loop, rather than being driven more by filter natural
frequency as in the target-following loop. Third, both the
lowest crossover frequency and the lowest phase margin of
the disturbance-rejection loop occurred in the no-motion
case.
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
0
1
2
3
4
Configuration
Crossover freq., mean and rms, rad/sec
1.0
0.0
0.9
0.2
1.0
0.5
1.0
0.9
0.7
0.2 0.7
0.5
0.3
0.2
0.3
0.5 0.4
0.9
0.0
0.0
K
w
Figure 58. Disturbance-rejection pilot-vehicle open-loop crossover frequencies.
46
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
0
10
20
30
40
50
Configuration
Phase margins, mean and rms, deg
1.0
0.0 0.9
0.2
1.0
0.5
1.0
0.9
0.7
0.2
0.7
0.5
0.3
0.2
0.3
0.5
0.4
0.9
0.0
0.0
K
w
Figure 59. Disturbance-rejection pilot-vehicle open-loop phase margins.
Total Tracking Error. Vertical tracking errors are
shown in figure 60. This error accrues from both the
target and the disturbance inputs. The four lowest errors
occurred for the lowest phase-error configurations, but the
differences between any two of the motion configurations
were not large. The Newman-Keuls results indicated that
all of the motion configurations, V1–V9, had better
performance than the no-motion V10, while no trackingerror
differences were present among the V1–V9 configurations
at the 5% level. Hence, the biggest effect on error
reduction was simply the presence of motion rather than
its characteristics.
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
0.0
0.5
1.0
1.5
2.0
2.5
Configuration
Tracking error, mean and rms, rad/sec
1.0
0.0 0.9
0.2
1.0
0.5
1.0
0.9
0.7
0.2
0.7
0.5
0.3
0.2
0.3
0.5
0.4
0.9
0.0
0.0
K
w
Figure 60. Vertical tracking errors.
47
Subjective Performance Data
Figure 61 provides the motion-fidelity ratings using the
definitions stated earlier. The ratings are divided into
“high,” “medium,” “low,” and “split,” where split refers to
a pilot assigning inconsistent ratings for repeated runs of
the same configuration. Split ratings only occurred for the
V1 configuration; this was more likely, because
configuration VI had more repeat evaluations than the
other cases. The ratings indicate that no pilot perceived the
K = 0.3 cases to be high fidelity. Configuration V2
received the best overall ratings, and also had the lowest
mean tracking error as shown earlier. Configuration V3
surprisingly received two low ratings; V4 received no low
ratings. Configuration V6, which is essentially a combination
of the natural frequency of V3 and the gain of V5,
was rated worse than either V3 or V5. No configurations
in which the high-pass filter’s high-frequency gain was
less than 0.3 was judged to be high fidelity. All pilots
rated the fixed-base condition to be low fidelity.
Summarizing the results of this section, the presence and
quality of motion influenced both target tracking and
disturbance rejection. Motion-filter natural frequency
affected both target tracking and disturbance rejection,
whereas motion gain affected only disturbance rejection.
Overall, the results from this dual task are consistent with
those presented in section 4.
Low
High
Medium
High, Medium, Low, Split
Fixed base
0,0,6,0 V10
80
60
40
20
0
0.6 0.8 1.0
Gain @ 1 rad/sec
0.0 0.2 0.4
Phase Distortion @ 1 rad/sec (deg)
0,5,1,0
V9
0,2,4,0
V8
1,5,0,0
V6 V3
3,3,0,0
V4
3,1,2,0
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Helicopter Flight Simulation Motion Platform Requirements(32)
