Improving Usefulness of Automated Driving by Lowering Primary Task Interference through HMI Design

Table 6

ANOVA results: usefulness and visual workload.

Dependent variable	Effect
Usefulness of HUD	HMI condition	1	15	5.15	.038	0.26
	HMI condition sequence	1	15	2.54	.132	0.14
	Driving situation	2	30	0.51	.603	0.03
	Driving situation sequence	2	30	0.97	.390	0.06
	HMI condition driving situation	2	30	1.46	.249	0.09
	HMI condition driving situation sequence	2	30	0.73	.492	0.05
	Sequence	1	15	0.01	.931	0.00
Usefulness of auditory output	HMI condition	1	15	1.81	.199	0.11
	HMI condition sequence	1	15	0.06	.812	0.00
	Driving situation	2	30	1.67	.206	0.10
	Driving situation sequence	2	30	0.69	.511	0.04
	HMI condition driving situation	2	30	3.36	.048	0.18
	HMI condition driving situation sequence	2	30	0.11	.897	0.01
	Sequence	1	15	9.96	.007	0.40
Visual workload	HMI condition	1	15	11.42	.004	0.43
	HMI condition sequence	1	15	3.52	.080	0.19
	Driving situation	2	30	2.23	.125	0.13
	Driving situation sequence	2	30	1.32	.283	0.08
	HMI condition driving situation	2	30	0.34	.717	0.02
	HMI condition driving situation sequence	2	30	1.42	.258	0.09
	Sequence	1	15	1.26	.279	0.08