tailieunhanh - Dynamic Vision for Perception and Control of Motion - Ernst D. Dickmanns Part 4

Tham khảo tài liệu 'dynamic vision for perception and control of motion - ernst d. dickmanns part 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Behavioral Capabilities for Locomotion 75 Transition Matrices for Single Step Predictions Equation with matrices F and G may be transformed into a difference equation with the cycle time T for grid point spacing by one of the standard methods. Precise numerical integration from 0 to T for v 0 may be the most convenient one for complex right-hand sides. The resulting general form then is X k 1 T A -x kT B u kT v kT or in short-hand notation xk 1 A xk B uk vk where the matrices A B have the same dimensions as F G. In the general case of local linearization all entries of these matrices may depend on the nominal state and control variables XN UN . The procedures for computing the elements of A and B have to be part of the 4-D knowledge base for the application at hand. Software packages for these transformations are standard in control engineering. For deeper understanding of motion processes of subjects observed a knowledge base has to be available linking the actual state and its time history to goal-oriented behaviors and to stereotypical control outputs on the time line. This will be discussed in Section . Once the initial conditions of the state are fixed or given the evolving trajectory will depend both on this state through matrix A the so-called homogeneous part and on the controls applied the non-homogeneous part . Of course this part also has to take the initial conditions into account to achieve the goals set in a close-to-optimal way. The collection of conditions influencing the decision for control output is called the situation to be discussed in Chapters 4 and 13 . Control Variables for Ground Vehicles A wheeled ground vehicle has three control variables usually two for longitudinal control and one for lateral control the steering system. Longitudinal control is achieved by actuating either fuel injection for acceleration or mild decelerations or brakes for decelerations up to -1 g Earth gravity acceleration m s 2 . .