SUMMARY Work relevant to the state of the art as regards passenger cars towing trailers is referenced and reviewed. Not only included is the very limited amount of work specifically dealing with passenger cars towing trailers, but also reviewed is the much larger body of work having a bearing on car-trailer systems. Topics included are aerodynamic forces, tire forces, the compliance concept, relevant work on vehicles without trailers, vehicles with trailers, and the role of the driver. The types of stability problems exhibited by car-trailer systems are discussed. The state of the art as regards ability to predict vehicle response to specific steering inputs is shown to be fairly advanced. Recent significant advances include the appearance of experimental data useful for validating theoretical models. However, the state of the art as regards definition of what constitute desirable handling characteristics is still at a primitive stage, largely because of a lack of understanding of the roles played by driv...

Handling Characteristics of Car-Trailer Systems; A State-of-the-Art Survey

Near time-optimal control of racing vehicles

A generalized theoretical model of tire cornering properties in steady state condition

Three wheel ground vehicle is not a traditional design primarily due to the stability consideration. However, after some detail analysis, it is shown that with careful design, three wheelers are not necessarily more unstable than four wheelers. Calculations in the current study are based on the Dugoff's tire deformation mechanism. Bicycle model is used. Vehicle motion is constrained on the ground. A critical speed is used as the quantitative index for stability. The current study reveals that for turning stability, with careful design, the 3W (2R) (2 rear wheels and 1 front whell) three wheeler is more stable than traditional four wheelers while 3W (2F) (2 front wheel and 1 rear wheel) possess least stability.

Stability analysis of three and four wheel vehicles

THE FAULT TREE ANALYSIS METHOD IS AN IMPORTANT NEW TECHNIQUE IN SAFETY ENGINEERING FOR COMPLEX SYSTEMS. THE RESULTS OF A MOTOR VEHICLE BRAKE SYSTEM SAFETY ANALYSIS USING THE TECHNIQUE ARE DESCRIBED. THE WORK IS DIRECTED TOWARD THE IDENTIFICATION AND RANKING OF BRAKE SYSTEM FAILURE MODES WHICH MAY BE CRITICAL AS ACCIDENT CAUSATION FACTORS. SAFETY CRITICALITY FOR EACH FAILURE MODE IS DEFINED AS THE PRODUCT OF PROBABILITY OF OCCURENCE AND SEVERITY OF EFFECT ON VEHICLE CONTROL. PROBABILITIES FOR THE BRAKE SYSTEM COMPONENTS ARE ESTIMATED FROM FAILURE DATA OBTAINED FROM MAINTENANCE AND REPAIR RECORDS OF A LARGE AUTOMOBILE LEASING FLEET. AN EFFECT SCALE IS DEVELOPED USING A METHOD FOR POOLING EXPERT JUDGEMENTS TO OBTAIN THE RELATIVE RANKING OF VARIOUS BRAKE FAULTS AS TO ACCIDENT CAUSATION POTENTIAL. THE FAULT TREE STRUCTURE IS EMPLOYED TO COMBINE PROBABILITY AND EFFECT TO OBTAIN THE SAFETY CRITICALITY VALUE OF EACH FAULT. RESULTS ARE INTERPRETED IN RELATION TO FEDERAL SAFETY STANDARDS AND MOTOR VEHICLE INSPECTION REQUIREMENTS. /AUTHOR/

Brake System Safety Analysis

Highway Vehicle Stability in Braking Maneuvers

PROBLEMS OF HIGHWAY VEHICLE DYNAMIC RESPONSE AND CONTROL IN EMERGENCY BRAKING MANEUVERS AND THE APPLICABILITY OF AUTOMATIC BRAKING CONTROL SYSTEMS FOR IMPROVING VEHICLE PERFORMANCE IN THESE MANEUVERS ARE DISCUSSED. IT IS SHOWN THAT AUTOMATIC BRAKING CONTROL SYSTEMS CAN IMPROVE VEHICLE RESPONSE AND HANDLING CHARACTERISTICS IN THE FOLLOWING AREAS: (1) STOPPING DISTANCE, (2) LATERAL STABILITY CHARACTERISTICS IN BRAKING MANEUVERS, AND (3) DIRECTIONAL CONTROL CHARACTERISTICS IN MANEUVERS WITH COMBINED BRAKING AND STEERING. THE METHOD OF APPROACH CONSISTS OF AN ASSESSMENT OF THE STATE-OF-THE-ART IN BREAKING CONTROL SYSTEMS; AN ANALYSIS OF THE EFFECT OF TIRE SLIP ON VEHICLE DYNAMIC RESPONSE; ESTABLISHMENT OF EFFECTIVENESS CRITERIA FOR THE EVALUATION OF THE DYNAMIC RESPONSE OF HIGHWAY VEHICLES IN EMERGENCY BRAKING MANEUVERS; AND HYBRID COMPUTER SIMULATION OF THE RESPONSE OF AN AUTOMOBILE EQUIPPED WITH AUTOMATIC BRAKING CONTROL. CONCLUSIONS AND RECOMMENDATIONS EMPHASIZE THE POTENTIAL BENEFITS TO HIGHWAY SAFETY TO BE GAINED WITH IMPROVEMENTS IN VEHICLE RESPONSE IN ACCIDENT AVOIDANCE MANEUVERS, AND IN PARTICULAR, THE APPLICATIONS OF AUTOMATIC CONTROL SYSTEMS IN THIS AREA. /AUTHOR/

Peter G. Fielding

Papers

Highway Vehicle Stability in Braking Maneuvers

Applicability of Braking Control Systems for Highway Vehicles