Automated driving vehicles are expected to be ready for series production by 2020. An important component of automated driving technologies is controlled path following under longitudinal speed control. In this paper, a robust path following controller design based on lateral deviation and yaw angle error determination of the vehicle is proposed. The constrained least square method is used for obtaining continuity and smoothness of the segment boundaries of the digital trajectory map to be followed. The lateral deviation and yaw angle error are calculated by comparing the generated digital map trajectory and the vehicle position. The parameter space approach is used in the design stage of the controller considering D-stability requirements. The solution regions of the controller are plotted in three dimensional parameter space. The designed controller is tested with simulations on a path chosen from the Ohio State University campus.

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The 2019 annual National Toxicology Program Satellite Symposium, entitled “Pathology Potpourri,” was held in Raleigh, North Carolina, at the Society of Toxicologic Pathology’s 38th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers’ talks along with select images that were used by the audience for voting and discussion. Various lesions and topics covered during the symposium included aging mouse lesions from various strains, as well as the following lesions from various rat strains: rete testis sperm granuloma/fibrosis, ovarian cystadenocarcinoma, retro-orbital schwannoma, periductal cholangiofibrosis of the liver and pancreas, pars distalis hypertrophy, chronic progressive nephropathy, and renal tubule regeneration. Other cases included polyovular follicles in young beagle dogs and a fungal blood smear contaminant. One series of cases challenged the audience to consider how immunohistochemistry may improve the diagnosis of some tumors. Interesting retinal lesions from a rhesus macaque emphasized the difficulty in determining the etiology of any particular retinal lesion due to the retina’s similar response to vascular injury. Finally, a series of lesions from the International Harmonization of Nomenclature and Diagnostic Criteria Non-Rodent Fish Working Group were presented.

This paper presents a multi-objective digital PID controller design method using the parameter space approach of robust control. Absolute stability is treated first by finding the digital PID controller gain parameter space corresponding to closed loop poles being inside the unit circle. Additionally, phase margin, gain margin and a mixed sensitivity bound are treated as frequency domain constraints. Determination of digital PID controller parameter space regions satisfying these constraints is presented. All of these regions are superimposed to obtain a multi-objective digital PID controller gain parameter space solution region. The path following controller design of an automated driving vehicle is used as an example to illustrate the method. This multi-objective parameter space design approach can be extended to other digital controller forms also.

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