What is the minimum turning radius of a car?

When the steering wheel turns to the limit position, the track circle diameter of the center of the front and outer steering wheel on the support surface will be given by the general model, and the minimum turning radius of the car is not related to the width of the car, but to the length of the car. However, the width of the turning lane is related to the width of the car. Minimum turning radius of all kinds of vehicles (m) Mini car 4.50 Mini car 6.00 Light car 6.50 ~ 8.00 Medium car 8.00 ~ 12.00 Articulated car 10.50 ~ 12.50 Ordinary fire truck 9.00 Large fire truck 12.00 Climbing fire truck 650 0 Part of special fire-fighting vehicles 16.00 ~ 20.00 The turning radius of urban road intersections is controlled according to the following standards: (according to the road red line) Main roads: 20m ~ 30m secondary roads:15m ~ 20m; Non-primary and secondary roads: 10m ~ 20m. In addition, motor vehicle entrances and exits should be more than 50 meters away from urban road intersections and starting and ending lines of bridges and tunnels. The turning radius of road red line in residential area shall not be less than 6m, and that in industrial area shall not be less than 9m. The minimum turning radius for roads with fire fighting function is 12m. The turning radius of the fire lane is 6m. The minimum turning radius of each car is different, mainly depending on the wheelbase of your car, and then depending on the tires of your car, the degree of exertion, some cars are larger, and it is not good for you to be like that big car. The minimum turning radius of a car largely represents the ability of a car to pass through a narrow bend or bypass an insurmountable obstacle. The smaller the turning radius, the better the maneuverability of the car. The minimum turning radius of all kinds of cars (m) The minimum turning radius of all kinds of cars (m) Mini car 4.50 Small car 6.00 Light car 6.50 ~ 8.00 Medium car 8.00 ~ 12.00 Articulated car 65438+ 00.50 ~ 12.50 Ordinary fire truck 9. 02.00 The directional stability of some special fire-fighting vehicles (16.00 ~ 20.00) is related to the handling stability of the vehicles and directly related to the driving safety of the vehicles, which has become one of the important performance indexes of modern vehicles. When any car turns, it has a turning radius. Let R be the distance from the longitudinal symmetry plane of the car to the instantaneous turning center O. Suppose the wheelbase of the car is L, the distance between the kingpins of the two front wheels is K, and β is the angle of the outer steering wheel, then the turning radius R is about L/sinβ. If the actual steering trajectory circle deviates from r, there will be understeer or oversteer. When it comes to understeer and oversteer, the term sideslip angle will be involved. When the car starts to turn at high speed, the car will instantly resist turning due to the inertia of the car driving forward, and then the tire cornering angle, that is, the included angle between the car driving direction and the wheel direction, will be generated. The cornering angle of the wheel is not only caused by the cornering characteristics of the tire, but also related to the structural factors of the suspension, such as the stiffness and geometric characteristics of the suspension. If the side slip angles of the front and rear wheels are equal, the actual turning radius of the car is equal to the turning radius corresponding to the steering wheel angle, which is called "neutral steering"; If the front wheel sideslip is greater than the rear wheel, the actual turning radius of the car is greater than the turning radius corresponding to the steering wheel angle, which is called "understeer"; If the sideslip of the rear wheel is greater than the sideslip of the front wheel, the actual turning radius of the car is less than the turning radius corresponding to the steering wheel angle, which is called "oversteer". Although neutral steering can make good use of the lateral force (the component perpendicular to the wheel direction) to reach the maximum steering speed, it weakens the driver's subjective feeling of vehicle stability and cannot predict the braking tail flick of the vehicle. However, when the speed reaches a certain limit, the steering radius will decrease sharply, and the car will spin, which will be difficult to control or out of control, and even lead to accidents. Understeering produces a relatively large steering radius, and the lateral force is weakened. This car is stable and easy to operate. As a result, most car manufacturers make their cars slightly understeer. In this case, the occurrence of brake deflection will make the car return to the original straight line. However, according to the specific situation, the car will adopt the design of oversteer to get the shortest turning time. The minimum turning radius refers to the radius of the locus circle where the center of the outer steering wheel rolls on the support plane when the steering wheel turns to the limit position and the car turns at the lowest stable speed. To a great extent, it represents the ability of a car to pass through narrow corners or bypass insurmountable obstacles. The smaller the turning radius, the better the maneuverability of the car. The way to adjust the minimum turning radius is to check and adjust the maximum steering angle of the front wheel first. The maximum steering angle of front wheel can be checked by special instrument or measured by simple method. Before measurement, check and adjust the toe-in of the front wheel, then park the car on the flat ground in a straight line, set up the front axle and make the height of the left and right wheels consistent, put a piece of white paper under the front wheel, stick the board on the outside of the tire, and draw the board marks on the paper. Finally, turn the roller left and right to the limit position, and draw the wooden board marks respectively. Measuring the included angle of wood marks on paper is the maximum steering angle of front wheels. If the maximum steering angle of the front wheel does not meet the requirements, adjust the length of the front wheel steering angle limit screw and adjust the rear locking screw. After the maximum steering angle of the front wheel is adjusted, it is necessary to check the minimum turning radius of the car. During the inspection, the car runs at a low speed on the flat ground. First, turn the steering wheel to the limit position and drive around, then adjust the circumferential diameter of the center of the front outer wheel mark of the automobile and measure the direction of the long axis and the short axis. Take the average value and then calculate the minimum turning radius (m) of various vehicles: mini-car 4.50, small car 6.00, light car 6.50 ~ 8.00, medium-sized car 8.00 ~ 12.00, articulated car 10.50 ~ 12.50 and ordinary fire truck 9.00. Special fire truck 16.00 ~ 20.00 Minimum turning radius for all kinds of vehicles. Minimum turning radius means 8.00~ 12.00m articulated truck 10.50~ 12.50m ordinary fire truck 9.00m large fire truck 12.00m climbing fire truck. 6.00~20.00m turning radius of urban road intersection The turning radius of urban road intersection is controlled according to the following standards: (calculated by road red line) Main road: 20 ~ 30m；; Secondary trunk road:15m ~ 20m; Non-primary and secondary roads: 10m ~ 20m. @20 19