Feedback factors in steering and tracking behavior.

Investigated the assumption that, in self-produced behavior, steering and target represent distinctive modes of reponse which are based, respectively, on perception and guidance of body movements in relation to the environment (steering) and on perception and guidance in relation to movement of environmental targets (stimulus tracking). These 2 modes of guided performance were compared using 7 Ss under controlled conditions in relation to the effects of feedback delay. Steering was degraded as much if not more than stimulus tracking by feedback delays between hand motion and the visual display involved in the different tasks. Steering performance, as in control of vehicles, thus may be affected seriously be feedback delays produced by powered steering and tracking devices and by inertia of action of a vehicle in relation to steering action at different speeds. Results theoretically clarify the feedback relations between self-produced and stimulus-response patterns of performance and learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

From vision to action: Experiments and models of steering control during driving.

Experienced drivers performed simple steering maneuvers in the absence of continuous visual input. Experiments conducted in a driving simulator assessed drivers' performance of lane corrections during brief visual occlusion and examined the visual cues that guide steering. The dependence of steering behavior on heading, speed, and lateral position at the start of the maneuver was measured. Drivers adjusted steering amplitude with heading and performed the maneuver more rapidly at higher speeds. These dependencies were unaffected by a 1.5-s visual occlusion at the start of the maneuver. Longer occlusions resulted in severe performance degradation. Two steering control models were developed to account for these findings. In the 1st, steering actions were coupled to perceptual variables such as lateral position and heading. In the 2nd, drivers pursued a virtual target in the scene. Both models yielded behavior that closely matches that of human drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delayed feedback in steering during learning and transfer of learning.

Compares accuracy in steering behavior as a characteristic mode of dynamic self-generation of stimuli by movement, with stimulus tracking in which response guidance is determined primarily by movements of environmental stimuli. Breath-generated variations in a visual target were used to measure steering of 24 female undergraduates. The hypotheses were that learning in tracking the respiration-generated targets would proceed more rapidly than that of tracking an environmental stimulus and that transfer of performance with the self-generated targets also would be superior. Results based on exact calibration of the equality of error control of the 2 modes of tracking confirm these assumptions. It was also found that steering and stimulus tracking were differentially affected in the learning and transfer trial series by manual-visual feedback delays between 0-1.5 sec. Results are explained theoretically by the assumption that steering reactions involved built-in stereotypical spatial and temporal coordinations between eye, hand, and body movements which were not present in the stimulus tracking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of feedback delay on eye-hand synchronism in steering behavior.

Used real-time computer methods of controlling feedback factors in eye tracking to compare accuracy in tracking environmentally-generated and hand-generated visual targets in steering behavior of 5 undergraduates. Feedback delays of .1 and .2 sec. between hand and target movement produced a time lag of eye motion with respect to the hand-produced target action. Results confirm the assumption that steering and stimulus tracking represent different modes of response and are subject to different conditions of delay and displacement of action feedback of body movements. The main effect of feedback delays on eye tracking in steering was to restrict the normal capability of the eye to predict the course of self-generated stimulus movements by reducing the interval of time between hand action and eye response beyond the magnitude of the actual delay interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental systems analysis of simulated vehicle steering and safety training.

Made an experimental feedback analysis of the human factors in steering, driver training, and automobile safety relative to the theory that steering is a distinctive form of self-guided activity distinct from stimulus tracking, and that the automobile is a special kind of wheeled exoskeleton. Results of systems experiments with 9 male undergraduates on delayed simulated driving, eye-hand synchronism in delayed steering, comparison between eye-hand coordination in steering and stimulus tracking, effects of road speed on steering error, and on effects of space displacement of steering visual feedback supported the view that the operator projects steering action relative to the space, time, and force compliances between driving responses, and the actions of the exoskeleton machine in relation to the feedback received from the road display. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feedback analysis of learning and performance in steering and tracking behavior.

Tested the assumption that steering and tracking behavior are interrelated in terms of the extent of self-produced stimulation involved in the 2 tasks. Steering was defined as involving maximal, and stimulus tracking as involving minimal levels of movement-regulated sensory information. 3 tasks steering, as governed by breath-produced target movement, stimulus tracking, and a hand-yoked target control task were compared under conditions in which the difficulty of the steering and stimulus tracking tasks were exactly equated. Results show that steering performance was more accurate and learned more rapidly than stimulus tracking. Oscillograph records of all aspects of performance indicate that the 2 tasks differed psychophysiologically in terms of how the self-timed respiratory activities and the external manual-visual responses were continuously and dynamically interrelated to control visual input. Results suggest that the modes and conditions of feedback control of dynamic sensory input not only determine accuracy of performance and rate of learning, but also define how internally-timed organic functions are integrated to determine learning in motor skills and other activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral dynamics of steering, obstable avoidance, and route selection.

The authors investigated the dynamics of steering and obstacle avoidance, with the aim of predicting routes through complex scenes. Participants walked in a virtual environment toward a goal (Experiment 1) and around an obstacle (Experiment 2) whose initial angle and distance varied. Goals and obstacles behave as attractors and repellers of heading, respectively, whose strengths depend on distance. The observed behavior was modeled as a dynamical system in which angular acceleration is a function of goal and obstacle angle and distance. By linearly combining terms for goals and obstacles, one could predict whether participants adopt a route to the left or right of an obstacle to reach a goal (Experiment 3). Route selection may emerge from on-line steering dynamics, making explicit path planning unnecessary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Controlling steering and judging heading: Retinal flow, visual direction, and extraretinal information.

The contribution of retinal flow (RF), extraretinal (ER), and egocentric visual direction (VD) information in locomotor control was explored. First, the recovery of heading from RF was examined when ER information was manipulated; results confirmed that ER signals affect heading judgments. Then the task was translated to steering curved paths, and the availability and veracity of VD were manipulated with either degraded or systematically biased RE. Large steering errors resulted from selective manipulation of RF and VD, providing strong evidence for the combination of RF, ER, and VD. The relative weighting applied to RF and VD was estimated. A point-attractor model is proposed that combines redundant sources of information for robust locomotor control with flexible trajectory planning through active gaze. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

汽车转向垂臂断裂原因分析

通过化学成分分析、硬度测试、金相检验及断口分析等对汽车转向垂臂断裂原因进行了分析,结果表明,转向垂臂退火态组织硬度未达到设计使用要求及臂身表面脱碳严重,导致材料的疲劳强度降低,,造成了转向垂臂的早期断裂。     

The role of visual and nonvisual feedback in a vehicle steering task.

This article investigates vehicle steering control, focusing on the task of lane changing and the role of different sources of sensory feedback. Participants carried out 2 experiments in a fully instrumented, motion-based simulator. Despite the high level of realism afforded by the simulator, participants were unable to complete a lane change in the absence of visual feedback. When asked to produce the steering movements required to change lanes and turn a corner, participants produced remarkably similar behavior in each case, revealing a misconception of how a lane-change maneuver is normally executed. Finally, participants were asked to change lanes in a fixed-based simulator, in the presence of intermittent visual information. Normal steering behavior could be restored using brief but suitably timed exposure to visual information. The data suggest that vehicle steering control can be characterized as a series of unidirectional, open-loop steering movements, each punctuated by a brief visual update. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Techniques for the study of group structure and behavior: I. Analysis of structure.

Recent advances in the development of mathematical techniques growing out of sociometry are described. Applications of these techniques are described. Applications of these techniques in assessing status, group structure, and the assignment of individuals to subgroups are suggested. Further use of these procedures should clarify the requirements for adequate explanatory systems and perhaps provide the variables to be incorporated in more comprehensive theories. 47-item bibliog. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Techniques for the study of learning in animals: Analysis and classification.

Present classifications of techniques for the study of animal learning are inadequate. The proposed classification is developed in terms of the functional significance of differences in technique. Thus 2 techniques differ if they yield results which differ in some fundamental respect but may be considered interchangeable if they produce similar results. The 3 major classifications are: Thorndikian Situations, Pavlovian Situations, and Avoidance Situations. Each major classification is subdivided to account for techniques appropriate to the specific situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Categorical distinctions in the study of personality disorder: Implications for classification.

Discusses the historical underpinnings of psychiatric classification and examines empirical evidence relevant to (1) whether personality disorders are distinct from each other and from normal personality and (2) whether personality disorders should be classified separately from other mental disorders. At the phenotypic level, research evidence strongly supports the use of a dimensional model to delineate personality disorders; evidence about their genotypic representation is less conclusive though still supportive. Neither empirical nor rational arguments indicate strong justification for separating personality disorders from other mental disorders, as has been done in both the Diagnostic and Statistical Manual of Mental Disorders-III (DSM-III) and DSM-IV. Distinctions between abnormal and disordered personality are considered, and suggestions are made for more satisfactory diagnostic classificatory schemes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Case study: Use of covert self-instruction for the elimination of psychotic speech.

Reports the systematic application of a self-instructional treatment program for the elimination of psychotic speech in a hospitalized 47-yr-old single male schizophrenic. Marked improvement of verbal behavior resulted in the patient's being discharged, and at 6-mo follow-up he was employed part-time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于蒙特卡罗法的轨迹再现转向机构稳健性设计

对于转向梯形机构,以转向过程的运动精度为目标函数,以主销中心距、轴距、转向梯形底角和转向梯形臂长度四个参数作为设计变量,以最小传动角及最大角度误差作为约束,建立了基于响应面方法的稳健设计数学模型.应用具有正态分布参数的蒙特卡罗稳健设计方法,对汽车转向机构进行了优化设计.比较了确定性优化方法与蒙特卡罗方法的设计结果.在转向角度误差相差不大的情况下,应用蒙特卡罗方法设计的转向机构最小传动角大,系统的传递性能及运动性能好,并且当设计变量出现微小变化时,能有效保证转向系统的运动轨迹.