Method For Dynamic Load Simulation By Means of Parallel Kinematics

Method according to any one of the preceding claims, characterized in that the following control algorithm (Fq,ref) is used:

• Fq,ref=JT(z)·[M(z)·z″+C(z, z′)·z′+g(z)+ufl,F],
• wherein ufl,F is a new system input for force control, JT(z) is a transposed Jacobian matrix, M(z) is a mass matrix, z is a position vector, C(z, z′)·z′ is a vector of generalized centrifugal and Coriolis forces and g(z) is a vector of generalized weight forces.

Method according to any one of the preceding claims, characterized in that a new system input (ufl,F) for force control is formed as follows:

• ufl,F=τ+RF(τref−τ)+RF,D(τ′ref−τ′),
• wherein τ, τ′, τref and τ′ref are load vectors that act between the end effector and the test object and RF and RF,D are control parameters formed as matrices.

Method according to the preceding claim, characterized in that the control parameters RF and RF,D are determined such that a control error differential equation converges to zero.

Method according to the preceding claim, characterized in that the e n algorithm (Fq,ref) is carried out according to the following equation:

• Fq,ref=JT(z)·[C(z, z′)·z′+g(z)+(1−S)·(M(z)·ufl,P+τ)+S·(M(z)·z″+ufl,F],
• wherein JT(z) is a transposed Jacobian matrix, C(z, z′)·z′ is a vector of generalized centrifugal and Coriolis forces, z is a position vector, g(z) is a vector of generalized weight forces, S is a selection matrix, M(z) is a mass matrix, τ is a load vector between the end effector and the test object, and ufl,P and ufl,F are the new system inputs for position and force control.

Method according to any one of the preceding claims, characterized in that a compensation controller, a general transmission element, a PID controller, or a PD controller with an additional sliding mode component is used for force and/or position control.

Method according to any one of the preceding claims, characterized in that a phase and/or amplitude drop in a band-limited force control loop is compensated by a phase and amplitude correction.

Method according to any one of the preceding claims, characterized in that the control algorithm (Fq,ref) is selected such that a model-based compensation of the non-linearities takes place according to the following equation:

• Fq,ref=JT(z)·[M(z)·ufl,P+C(z, z′)·z′+g(z)+τ],
• wherein JT(z) is a transposed Jacobian matrix, M(z) is a mass matrix, ufl,P is a new system input for force control, z is a position vector, C(z, z′)·z′ is a vector of generalized centrifugal and Coriolis forces, g(z) is a vector of generalized weight forces and τ is a load vector between the end effector and the test object.

Method according to any one of the preceding claims, characterized in that the control algorithm (Fq,ref) is selected such that the target loads by the actuators are used as the variable (τq,ref) to be iterated:

• Fq,ref=JT(z)·τq,ref,
• wherein τq,ref are the target loads between the end effecter and the test object and JT(z) is a transposed Jacobian matrix.

Method according to any one of the preceding claims, characterized in that the parallel kinematic excitation unit is a hexapod.

Method according to any one of the preceding claims, characterized in that the measuring of loads at the contact point is carried out by a force measuring wheel.

Method according to any one of the preceding claims, characterized in that the test object is a vehicle axle.

Method according to any one of the preceding claims, characterized by defining target signals (100) for loads to be applied to the contact point between the end effector and the test object, wherein this is implemented prior to the step of measuring loads at the contact point (200).

Method according to any one of the preceding claims, characterized by applying the target signals (500) to the end effector by means of a control of the target pressures for the actuators determined by the control algorithm (Fq,ref), wherein this is implemented subsequently to the step of determining the target pressures (400) for individual actuators of the parallel kinematic excitation unit.

System for dynamic load simulation between a parallel kinematic excitation unit and a test object, comprising components suitable for carrying out method steps according to at least one of the preceding claims.