Table 1.

Summary of the features used on the inertial sensors signals to detect initial contact (Ic) and terminal contact (Tc).

Detection zone	Feature			Description
	Signal	Rule	Label
Initial contact (IC)	ωp	MIN	k1	Minimum of the pitch angular velocity
		ZeroX	k2	First zero-crossing of the pitch angular velocity
		MINloc < -100 °/s	k3	First local minimum smaller than 100°/s on the pitch angular velocity
	ω’p	MAX	k4	Maximum of the pitch angular acceleration
		MIN before k4	k5	Minimum of the pitch angular acceleration before k4
	ω”p	ZeroX	k6	Last zero-crossing of the pitch angular jerk before k4
	||ω||	MAX	k7	Maximum on the angular velocity norm
	Avert	MAX	k8	Maximum of the vertical acceleration
	||A||	MAX	k9	Maximum of the acceleration norm
		MIN before k9	k10	Minimum of the acceleration norm before k9
		MINloc	k11	First local minimum of the acceleration norm
	||A||’	ZeroX	k12	Last zero-crossing of the jerk
Terminal contact (TC)	ωp	MIN	t1	Minimum of the pitch angular velocity
	ω’p	ZeroX after t1	t2	First zero-crossing of the pitch angular acceleration after t1
	ωr	ZeroX after t1	t3	First zero-crossing of the roll angular velocity after t1
	||ω||	MAX	t4	Maximum of the angular velocity norm
	Avert	MAXloc after t1	t5	First local maximum of the vertical acceleration after t1
	Along	MIN	t6	Minimum of the longitudinal acceleration
	Acoro	MAXloc after t1	t7	First local maximum of the coronal acceleration after t1
	||A||	MAX	t8	Maximum of the acceleration norm
		MAXloc after t1	t9	First local maximum of the acceleration norm after t1

IC candidates are identified by kj with j ∈{1.. 12} and TC candidates are identified by tj with j ∈{1.. 9}. The features presented in this table were used in the respective detection zone of IC and TC.