Accession Number : ADA218948


Title :   Control of Randomly Sampled Robotic Systems


Descriptive Note : Interim technical rept.


Corporate Author : PENNSYLVANIA UNIV PHILADELPHIA SCHOOL OF ENGINEERING AND APPLIED SCIENCE


Personal Author(s) : Kobayashi, Hiroaki ; Yun, Xiaoping ; Paul, Richard P


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a218948.pdf


Report Date : May 1989


Pagination or Media Count : 97


Abstract : This paper studies control problems of sampled data systems which are subject to random sample rate variations and delays. Due to the rapid growth of the use of computers more and more systems are controlled digitally. Complex systems as space telerobotic systems require the integration of a number of sub-systems at different hierarchical levels. While many sub-systems may run on a single processor, some sub-systems require their own processor or processors. The sub-systems are integrated into functioning systems through communications. Communication between processes sharing a single processor are also subject to random delays due to memory management and interrupt latency. Communications between processors involve random delays due to network access and to data collisions. Furthermore, all control processes involve delays due to causal factors in measuring devices and to signal processing. Traditionally, sampling rates are chosen to meet the worst case communication delay. Such a strategy is wasteful as the processors are then idle a great proportion of the time; sample rates are not as high as possible resulting in poor performance or in the over specification of control processors; there is the possibility of missing data no matter how low the sample rate is picked. Keywords: Statistical analysis.


Descriptors :   *INFORMATION SYSTEMS , *ROBOTICS , *STATISTICAL SAMPLES , *SYSTEMS ANALYSIS , ACCESS , COLLISIONS , COMMUNICATION AND RADIO SYSTEMS , COMPUTERS , CONTROL , DELAY , GROWTH(GENERAL) , HIERARCHIES , HIGH RATE , MANAGEMENT , MEASUREMENT , MEMORY DEVICES , NETWORKS , PROCESSING EQUIPMENT , RATES , SAMPLING , SIGNAL PROCESSING , SPECIFICATIONS , STATISTICAL ANALYSIS


Subject Categories : Statistics and Probability
      Computer Hardware
      Cybernetics


Distribution Statement : APPROVED FOR PUBLIC RELEASE