Improvements derived from semestral work

Dobrý den,

zkusil jsem posbírat a uklidit skripty, které jsem v semestrálce použil.

JV

data/students/data/README.md

+# Measured data
+
+This dataset contains different types of experiments:
+ * responses to steps in road height,
+ * responses to steps in actuator force,
+ * responses to sine sweep in road height,
+ * responses to sine sweep in actuator force.
+
+The data format is similar to the format used for the original identification
+dataset. The data can be loaded into Matlab workspace using
+
+```matlab
+load road_step_slow.mat
+```
+
+Up to three new data structs will then appear in the workspace:
+
+- `measured_pos_ol_response`
+  - This struct contains the measured road height and the heights of lower and upper masses.
+  - The columns correspond to `[zr zus zs]` -- road height, lower mass height and upper mass height.
+  - This struct is always present.
+- `measured_acc_ol_response`
+  - This struct contains a **low-pass-filetered** signal from the accelerometer mounted on the upper mass.
+  - The columns correspond to `[acc]` -- just the accelerometer signal.
+  - The low-pass filter is a second-order low pass filter with ωₙ = 70 rad/sec and ζ = 1.
+  - This struct is sometimes missing.
+- `control_signal`
+  - This struct contains the signals that were sent into the physical model.
+  - The columns correspond to `[zr_ref actuator_out]` -- road height reference and actuator output signal.
+  - This struct is sometimes missing. However, it is never missing when the
+    file contains a response to a change in actuator force -- this struct
+    contains which exact signal was applied.
+
+This can be demonstrated by plotting the data:
+```matlab
+figure(1) 
+plot(measured_pos_ol_response.time, measured_pos_ol_response.signals.values)
+legend('zr','zus','zs')
+xlabel('Time [s]')
+ylabel('Measured positions [m]')
+grid on
+
+figure(2)
+plot(measured_acc_ol_response.time, measured_acc_ol_response.signals.values)
+legend('d2/dt2 zs')
+xlabel('Time [s]')
+ylabel('Measured acceleration [m/s2]')
+grid on
+
+figure(3)
+plot(control_signal.time, control_signal.signals.values)
+legend('target road height', 'actuator output signal')
+xlabel('Time [s]')
+ylabel('Control signal [-]')
+grid on
+```
+
+## List of experiments:
+
+### Actuator step
+ - `actuator_step.mat` - basically that.
+
+### Actuator sweep
+ - `actuator_sweep.mat` - sweep from "middle" to "high" frequencies.
+ - `actuator_sweep_lf.mat` - sweep covering "low" frequencies.
+ - `actuator_sweep_lf_longer.mat` - sweep trying to cover the resonant peak of the model.
+ - `actuator_sweep_lf_longer_v2.mat` - sweep trying to cover the resonant peak of the model.
+ - `actuator_sweep_reversed.mat` - sweep from going from "high" to "middle" frequencies. The goal of this experiment to reduce the effect of static friction at low frequencies.
+
+### Road step
+ - `road_step_slow.mat` - response of the system when the road platform is subjected to ramped steps in the reference signal.
+ - `road_step_fast.mat` - response of the system when the road platform is subjected to immediate jumps in the reference signal.
+   This goal of this experiment was to excite the system more than in `road_step_slow.mat`.
+
+### Road sweep
+ - `road_sweep_normal.mat` - sweep from "middle" to "semi-high" frequencies.
+ - `road_sweep_normal_2.mat` - sweep from "middle" to "semi-high" frequencies.
+ - `road_sweep_long.mat` - sweep from "middle" to "high" frequencies.
+ - `road_sweep_normal_reversed.mat` - sweep from "high" to "middle" frequencies. The goal was again to reduce the effect of static friction.
+ - `road_sweep_lf.mat` - sweep covering "low" frequencies.