Tham khảo tài liệu 'dynamic vision for perception and control of motion - ernst d. dickmanns part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Planar Roads with Minor Perturbations in Pitch 255 spatial continuity conditions for the road as temporal continuity constraints in the form of difference equations for the estimation process while the vehicle moves along the road. By this choice the task of recursive estimation of road parameters and relative egostate can be transformed into a conventional online estimation task with two cooperating dynamic submodels. A simple set of equations for planar undisturbed motion has been given in Chapter 7. In Chapter 8 the initialization problem has been discussed. The results for all elements needed for starting recursive estimation are collected in Table . Numerical values for the example in Figure extracted from image data have been given in Table . The steering angle X and vehicle speed V are taken from conventional measurements assumed to be correct. The slip angle p cannot be determined from single image interpretation and is initialized with zero. An alternative would be to resort to the very simple dynamic model of third order in Figure and determine the idealized value for infinite tire stiffness as indicated in the lower feed-forward loop of the system p 1 2-V2 2a kf X. The estimation process with all these models is the subject of the next section. Planar Roads with Minor Perturbations in Pitch When the ground is planar and the vehicle hardly pitches up during acceleration or pitches down during braking deceleration there is no need to explicitly consider the pitching motion of the vehicle damped second-order oscillations in the vertical plane since the measurement process is affected only a little. However in the real world there almost always are pitch effects on various timescales involved. Acceleration and decelerations usually do affect the pitch angle time history but also the consumption of fuel leads to very slow pitch angle changes. Loading conditions of course also have an effect on pitch angle as well as uneven surfaces
