A method implemented by computer, for controlling a mechanical compatibility between a passenger and a vehicle by determining, by reanalysis, a vibratory environment of a coupled system comprising the vehicle and the passenger, the vehicle being subjected to external forces Fext and being coupled to a passenger comprising x =1,..., N load(s), said vibratory environment being characterized by interfacial accelerations at vehicle/passenger interfaces lx, the method being characterized in that it comprises a step DET1) of determining, on the basis of the reference interfacial acceleration(s) γ x_ref of a reference passenger, interfacial acceleration(s) γ x ′ relating to a new passenger by means of the following relationship γ x ′ ω = I + M REF TOT − 1 ω ΔM x P ω − 1. γ x _ ref ω with - γ xref ( ω): vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the reference passenger; - γ x ′ ω: vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the new passenger; ΔM x P ω = M x P ω − M ref P ω; - M x P ω: the dynamic mass operator of the new passenger interface; - M ref ω P: the dynamic mass operator of reference passenger interface; - M REF TOT ω: the dynamic mass operator of the vehicle coupled to the reference passenger interface; the operators M x P ω, M ref ω P and M REF TOT ω being obtained by a direct approach in the following manner: M ω = 1 − ω 2 − ω 2 M jj + j ωC jj + K jj + jH jj + − ω 2 M ji + j ωC ji + K ji + jH ji − ω 2 M ii + j ωC ii + K ii + jH ii − 1 ω 2 M ij + j ωC ij + K ij + jH ij - M mass matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - K stiffness matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - C viscous damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - H the hysteretic damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - I: the identity matrix. the method being characterized in that it comprises a step DET1) of determining, on the basis of the reference interfacial acceleration(s) γ x_ref of a reference passenger, interfacial acceleration(s) γ x ′ relating to a new passenger by means of the following relationship γ x ′ ω = I + M REF TOT − 1 ω ΔM x P ω − 1. γ x _ ref ω with - γ xref ( ω): vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the reference passenger; - γ x ′ ω: vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the new passenger; ΔM x P ω = M x P ω − M ref P ω; - M x P ω: the dynamic mass operator of the new passenger interface; - M ref ω P: the dynamic mass operator of reference passenger interface; - M REF TOT ω: the dynamic mass operator of the vehicle coupled to the reference passenger interface; - γ xref ( ω): vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the reference passenger; - γ x ′ ω: vector of accelerations on all degrees of freedom of the vehicle/passenger interface for the new passenger; ΔM x P ω = M x P ω − M ref P ω; - M x P ω: the dynamic mass operator of the new passenger interface; - M ref ω P: the dynamic mass operator of reference passenger interface; - M REF TOT ω: the dynamic mass operator of the vehicle coupled to the reference passenger interface; the operators M x P ω, M ref ω P and M REF TOT ω being obtained by a direct approach in the following manner: M ω = 1 − ω 2 − ω 2 M jj + j ωC jj + K jj + jH jj + − ω 2 M ji + j ωC ji + K ji + jH ji − ω 2 M ii + j ωC ii + K ii + jH ii − 1 ω 2 M ij + j ωC ij + K ij + jH ij - M mass matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - K stiffness matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - C viscous damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - H the hysteretic damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - I: the identity matrix. - M mass matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - K stiffness matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - C viscous damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - H the hysteretic damping matrix of the reference passenger, the new passenger or the vehicle coupled to the reference passenger; - I: the identity matrix.