Fig 1.
Chronogical order of road segments.
Participants drove on 15 segments of 4 road types: 4 City segments (Ci), 5 Highway segments (Hi), 3 Country segments (Co), and 3 Mountain segments (Mo).
Fig 2.
For each seat, main geometrical dimensions and values of bearing capacity and density for the seat cushion and backrest.
Fig 3.
Force vs Displacement (FvsD) for the three seats tested.
A test of foam hardness was conducted at CTAG and is illustrated in the pictures. The graph illustrates the FvsD for each seat cushion and each backrest. The force was applied by a rigid dummy. For the same force applied, cushion displacement was highest for S3, followed by S1 and finally S2, thereby defining S3 and S1 as soft seats and S2 as a firm seat.
Fig 4.
Representation of pressure mat areas.
Spatial division of pressure mats to analyze 4 areas for the backrest (Right/Left Upper back and Lower back) and 6 areas for the cushion (Right/Left Buttocks, Thighs and Bolsters).
Fig 5.
Pressure parameter evolution on full cushion mat for each road segment.
A) Evolution of CP. B) Evolution of CS. * represents significant differences between segments for the same road type (*: p<0.05; **: p<0.01; ***: p<0.001). Colored * represents one seat, black * represents three seats. § represents significant differences between two successive segments (§: p<0.05; §§: p<0.01; §§§: p<0.001).
Fig 6.
Evolution of the uniformity or pressure distribution represents with SPD% score. * represents significant differences between segments for the same road type (*: p<0.05; **: p<0.01; ***: p<0.001).
Fig 7.
Distribution of CP by area of backrest and cushion. Each shade of color represents a significant difference (p<0.05).
Fig 8.
Distribution of CS by area of backrest and cushion. Each shade of color represents a significant difference (p<0.05).
Fig 9.
Pressure parameter evolution on full backrest mat for each road segment.
A) Evolution of CP. B) Evolution of CS. Symbol * represents significant differences between segments for the same road type (*: p<0.05; **: p<0.01; ***: p<0.001). Colored * represents one seat, black * represents three seats. § represents significant differences between two successive segments (§: p<0.05; §§: p<0.01; §§§: p<0.001). ¤ represents significant differences between seats (¤: p<0.05; ¤¤: p<0.01; ¤¤¤: p<0.001).
Fig 10.
Frequency of RM for each road segment.
A) Backward RM. B) Forward RM. * represents significant differences between segments for the same road type (*: p<0.05; **: p<0.01; ***: p<0.001). Colored * represents one seat, black * represents three seats. § represents significant differences between two successive segments (§: p<0.05; §§: p<0.01; §§§: p<0.001). ¤ represents significant differences between seats (¤: p<0.05; ¤¤: p<0.01; ¤¤¤: p<0.001).
Fig 11.
A) Mean scores for whole-body discomfort throughout driving session. Significant increases in discomfort compared to score at t1 are represented by ***: p<0.001. B) Visual representation of mean of local discomfort. A color scale shows scores as a percentage of maximum values for each body part.