The fsrte02 chassis and suspension design had to be feasible, makeable and completely finished. Under acceleration, a low antidive geometry will cause the front end to lift and the suspension to extend which also shifts weight to the rear of the vehicle. As the brakes are applied, weight is transferred to the front and that forces the front to dive. If a point is reached called 100percent antidive, all of the load transfer is resisted by the suspension arms and none is carried through the springs. Tips on choosing scratchbuiltlate model stock car books. In my point of view it had to be a continuation of the work of wouter berkhout.
Design, analysis, and verification of an openwheeled. This seems to have a greater effect on suspension than the inertia induced antidive. What this book is is a very nice tour and look back over a very fine career from a relatively high altitude occasionally dipping lower for limited conceptual interjections pertaining to the art of race car design. Antidive and squat are carefully engineered geometries that prevent the weight transfer of a car from being routed through the springs and dampers of the suspension what this translates to is a level ride height under braking or acceleration. Common design targets seem to often be in the 50 to 100percent range. The main reason for the difference is due to the different design goals between front and rear suspension, whereas suspension is usually symmetrical between the.
Conceptually, anti dive is not really a difficult geometric program to understand. It is important for the suspension to keep the road. From the side view of your front suspension you have pivot points for the. The main reason for the difference is due to the different design goals between front and rear suspension. The suspension system comprises antisquat and antidive element. Its not just a coffee table book with nice pictures i did enjoy and appreciate the shared recollections. This can cause the car to become unpredictable and therefore it is important to minimise this effect. In either circumstance, it is useful for you to have a good knowledge of vehicle dynamics so that the handling of the car can be understood during setup and racing. Having the links or arms parallel and level with the ground gives a 0% antidive in both forms. Antidive and antisquat are expressed in terms of percentage and refer to the front diving under braking and the rear squatting under acceleration. The spring and the suspension arms are sharing the load in some proportion. Antidive geometry will limit the front end dive giving the driver greater confidence. The vehicle model is employed to study the effect of these features upon. Designs which fit into this category include, hub centre steered designs such as difazio, bimota etc.
Adding anti dive to the front suspension also gives some other effects. As antidive is added, a portion of the load transfer is resisted by the suspension arms. Design of three and four link suspensions for off road use. Front suspension technology link basics part 2 offroad. He provides design theory and practical information on tires, wheels, suspension geometry, springs, antiroll bars, brakes, aerodynamics, handling, engine supports, chassis, safety and even racing operations such as testing and pit lane procedures. Do we apply antisquat and antidive characteristics to. This is why the first chapter in each book is about tires, the. Suspension systems must support both road holdinghandling and ride quality, which are at odds with each other. Anti dive is dependant on the vehicles center of gravity, the percentage of braking force developed at the front tires vs the rear, and the design of the front suspension. There are entire books dedicated to the subject, and this paper is intended. Suspension key performance indicators kpis can be used to understand how a suspension system will perform under different driving conditions, e. Whilst discussing independent rear suspension, he states. They can be thought of as the counterparts for braking and acceleration as roll center height is to cornering. Suspension systems with antidive values under 100% will cause the front suspension to compress under breaking, often called nosedive.
Suspension is the system of tires, tire air, springs, shock absorbers and linkages that connects a vehicle to its wheels and allows relative motion between the two. Suspension geometry part 1 camber, toe, caster, kpi. All kinds of forces and movements between the wheels and the ground passes to the body through the suspension. Pdf influence of antidive and antisquat geometry in combined. Anti dive describes the amount the front of the vehicle dives under breaking. Suspension key performance indicators kpi suspension. Design and optimization of formula sae suspension system. With too much anti dive, the axle may want to droop out, rather than allowing the tires to climb an obstacle. Design of a suspension for a formula student race car slideshare. Mainly you need to define the type of system you are going to use in your front and rear suspension. The suspension system is a device connecting the body with wheels. Yes if the fabrication is done exactly as design we could achieve anti dive or anti squat design. The main reason for the difference is due to the different design goals between front and rear suspension, whereas suspension is usually symmetrical between.
Dive is design to suspension based on the angle of the. Stock cars can be built from a prefab chassis or from a scratch design. With too much antidive, the axle may want to droop out, rather than allowing the tires to climb an obstacle. As a vehicle brakes, the front has a tendency to dive. Antidive suspensions are used to reduce body dive by altering the front suspension so that the forces resulting from braking pass through the. The tuning of suspensions involves finding the right compromise. A definition of anti dive as it pertains to motorsports suspensions. It is torque induced instead of inertia induced liked i mentioned above. Honestly, if you dont have a book on suspension design and are planning on designing a car its a good time to get some books.
109 169 662 779 913 1148 689 707 1073 996 960 393 1004 1077 1318 1048 116 1482 993 993 240 1405 1140 919 534 1418 210 755 222 771 496 605