2.3.1. Simulator Research

The simulator tests concerned the analysis of two cases: the "route" type ride, shown in Figure 3a [7], and the "slalom" type ride, shown in Figure 3b [8].

**Figure 3.** (**a**) "Route" type adapted from [7], (**b**) "slalom" type adapted from [8].

The "route" type ride consisted of straight sections connected by a circular curve (Figure 3a). The recording of the experiment began after reaching the speed of 50 km/h. In the second straight section, the driver had to maneuver around the obstacle (typical for the "moose" test). The "slalom" ride required a simultaneous change in speed and direction of driving, as shown in Figure 3b. In the first case, the driver's task was to follow the centerline of the lane; in the second, to follow the reference space-time line, i.e., the driver had to change speed in line with the reference space–time line (this required intensive use of acceleration and braking O-rings). Each of the tested drivers performed four runs: one training run and three runs with a steering wheel of the NOR type (the gear ratio in a typical car: two and a half turns of the steering wheel correspond to a turn of the wheels by approx. ±35 degrees), one with an ECO 180 steering wheel (the ratio of 180 degrees of the steering wheel rotation corresponds to approx. ±35 degrees of the wheels rotation), and the ECO 120 steering wheel (the ratio of 120 degrees of steering wheel rotation–approx. ±35 degrees of the wheels' rotation). The influence of the gear ratio on the "driving accuracy" was analyzed. The simulator screen is shown in Figure 4.

**Figure 4.** Simulator screen image: reference trajectory.

Defining the driving evaluation criteria was essential. Three criteria (measures) were used here: the first: the technical one, the second: the biomedical nature one based on the EMG measurement, and the third: based on the assessment of the experiment participants' survey. The measurements for a maneuver's correctness were:

• Mean square deviations from the lane centerline (in relation to time or distance)

$$\text{RMS1} = \left(\frac{1}{T} \int\_0^T s^2(t)dt\right)^{1/2} \text{ or } \text{RMS2} = \left(\frac{1}{\Lambda} \int\_0^\Lambda s^2(\lambda)d\lambda\right)^{1/2} \tag{2}$$

where *T* is the duration of the experiment, 5000 (s); Λ is route length; *s* is deviation from the lane centerline measured along the normal to the curve.

• Mean square deviations of the speed from the reference speed

$$RMS = \left(\frac{1}{T} \int\_0^T delta \, t dV^2(t) dt\right)^{1/2} \tag{3}$$

where *T* is the duration of the experiment, 5000 (s); *deltaV* is deviation from the set speed. The EMG analysis procedure was based on the signal obtained as a result of the

applied surface electromyography.
