Which suspension setup is the best for an fsae or student. Design of a suspension system for a formula student. The bell crank ratio has been tuned to provide a slightly rising compression relationship between wheel movement and damper movement. In this video i explain how formula 1 incorporates push rod suspensions into their design. Mostly rear pull rod can interfere with your drive shafts. Design and optimization of formula sae suspension system. Design of suspension system for formula student race car core. The wishbones and the push rod just takes either push or pull forces because they can rotate around the bearings on their ends. The chosen design was a pushrod double wishbone suspension system and followed. The fine adjustment of the comfort characteristics of a passenger car in an early phase of development of the vehicle is dependent on an efficient and meaningful test and simulation technique to analyse the vertical and horizontal dynamics of the system tyrewheel suspension. A variation on the radius arm suspension is the parallel fourlink, shown in the figure above. Design and modeling of pull rod and push rod suspension system. With ferrari having opted for a pullrod suspension for the front end of its f2012, the. It is the push rod which has the there are no tapered plies within the stacking sequence.
Some software includes kinematic capabilities that simulate vehicle dynamics using the designed suspension. In this work, we presented in detail the design procedure of the front double aarm push rod suspension system for a formula student race car. Pushrod and pullrod suspension are similar yet distinct in design, with the main difference being the placement of the rocker arm that. Design and strength analysis of fsae suspension were also proposed. The computeraided design cad files and all associated content posted to this website are created, uploaded, managed and. But a suspension has a lot more to do, so the cog should not be the reason for choosin gthe design. Later on the assembly of all parts and mono spring rocker arm front suspension system were designed. Later, the assembly of all parts and mono spring rocker arm fro. The goal is to use an unequal length double a arm wishbone setup. The dynamic loads are to be considered for the design of wheel assembly. The main advantage of a pull rod lie in the possibility to make the nose lower, assemble most suspension parts lower to the ground and thus lowering the height of the centre of gravity. Suspension design determine loads to properly design the suspension components the. Pushrod ratio calculation help hey guys, playing with my front suspension and need some help. The main criterion of this project is to design a suspension system practically to a.
How to calculate and design pushrod suspension for. The only major difference between the two is that the front suspension also includes the steering system you can check out my other parts to my hybrid rocketpowered rc car project. As known, pull rod helps in reducing the cg, which is not a negligible one but pull rod system poses a lot of packaging difficulties. Ferraris launch of its radical f2012 brought the return of pullrod suspension to the front end of the car, an idea thought impractical with the current high noses. Choice between the two is geometry and cog centre of gravity. Up until the end of 2011, all teams had been using a pushrod suspension at the front and a pullrod suspension at the rear for almost a decade. There are dozens of variations of suspension types used on race and passenger vehicles. Lowe commented that the lotus brake antidive system was not specifically looked at, but was part of a family of solutions. Pull rods were first brought to formula 1 by gordon murray with brabham in the 70s but gradually disappeared at the rear and then also at the front when teams started using. Lower lateral link, upper reversed aarm, twin trailing links rear a variation on the above. The pushrod will be under compression, while the pullrod will be under tension. In push rod suspension, the suspension arm is usually at a 45 degree angle to the bodyworktyre in an f1 car. Regardless of the type of vehicle you are building we have the products and free information that will save you time and money.
Pushrod suspension is something that can be easily shaped to suit the greatest concerns in vehicle design. Users can also create and distribute their own templates. Firstly, according to the whole layout of fsae racing, the suspension mode was selected, both front and rear suspension were unequal push rod type double wishbone independent suspensions. Lotus shark suspension analysis software is used for dynamic analysis of. The pros and cons of ferraris pullrod design f1 autosport plus. Hello and welcome to sva design if you enjoy this content please leave us a like and subscribe to our youtube channel. Find out how the suspension on a formula e car works with our indepth technical guide. Full vehicle version also includes push rod and pull rod springs for double a arm. Aftermarket manufacturers make kits that retrofit an existing radius arm suspension to a parallel fourlink design and use coil springs and a track bar to center the axle.
Car 4 is one of the most well known multibody dynamics simulation software on. Craig scarborough looks at the pros and cons of the design. Design of suspension system for formula student race car. Im now sleeping much better thanks to your program. Pushrod or pullrod, the difference as the name suggests is the whether the rod push up to the rocker or pull down to the rocker. He describes design requirements such as lateral control, roll center height, bump steer, and antisquat for the various types of live axle suspension. This requires a suspension design that is both road friendly but also able to give the handling characteristics needed for track use.
The car uses a lot of parts from an old vw beetle which puts a limit on how good the vehicle dynamics may be in. Adjustable pushrod suspension design andrew bayer 1 abstract the caterham is a type of car used mostly for everyday driving, but also for occasional trips to the racetrack. The center of gravity cog is lower in pull rod suspension while it is harder to. What is the difference between pull rod and push rod. Push rod in push rod suspension, the suspension arm is usually at a 45 degree angle to the bodyworktyre in an f1 car. These parameters can be used to determine the spring travel that has to be achieved. In this section, the author moves to the rear of the car, where live axle rear suspension design is discussed.
Manufacturing and ultimate mechanical performance of. Be sure to check out my video on pushrod suspensions. These bars are what supports the vehicle on the suspension by transferring the weight to the rocker arms, which are splinted to torsion bars. This paper presents the procedure of design and analysis both kinematic and dynamic of the front double aarm push rod suspension system for a formula student race car. Front and rear suspension analysis simulation software program. As mclaren have experience this year, and ferrari last year, pull rods can be difficult to set up, and a good car has to have an easily adjusted and very flexible no pun intended suspension in order to be fast on all tracks. Lister storm lmp designer reveals his trade secrets for suspension design. Suspension experts point out that pull rod suffers similar compression bending when the suspension is in droop wheels falling, but droop is considered less critical in wheel control, than bump. Suspension changes are especially critical to your vehicles handling and should be well understood and well designed. The classis 60s sports and racing car rear suspension. Theres no one answer to which is best, you look at your design requirements and. Suspension design software is invaluable in car or truck design as it does the heavy lifting when it comes to the many iterations of manual calculation that are usually needed to find the ideal geometry.
Its often said there is nothing new in f1 in terms of design. Software for designing and analyzing suspension systems and geometry. Upper lateral link, lower parallel links, twin trailing link rear a variation of the reversed lower aarm style. Also a pull rod will flex in droop wheel going down and push rod will flex with the wheel in bump wheel going up hence f1 push or pull rods are large carbon molding to withstand the flexing from the high wheel loads. Pull rod suspension remains at the rear of the car, while conventional pushrod is on the front end. To modify the chassis, driveline or suspension will require design knowledge in these areas. Differences between pullrod and pushrod suspensions pro. Full vehicle version combines front and several types of rear suspensions together for full roll couple analysis, or analyze front or rear separately for rear roll steer, pinion angle change, antisquat, etc. There is not much change compared to the front and rear suspension systems. There are 10 key factors to be considered when designing a suspension system, whether its for a single seater or sports prototype, and part of the skill of the designer lies in reconciling the conflicts between them. Formula one pullrod suspensions, like those used by ferrari for the 2012 series will be examined in this video. Design of formula sae suspension theory in practice.
When the car goes over a bump the movement is transferred through the tyre and rim to the suspension upright and then into t. How pushrod suspensions work formula 1 explained youtube. A pull rod goes the other way, connecting a rocker located low in the chassis, with the upper side of the wheel, almost where the upper suspension arms meet the upright. However, the change from metal to composite response of this push rod design would be a lower bound. The main advantage of a pull rod lie in the possibility to make the nose lower, assemble most suspension parts lower to the ground and. Solidworks pull rod suspention design speed art sva. This is the source for tech tips, blue prints, drawings and plans for the do it yourself automotive hobbyist. This paper describes the development of a vehicle suspension analysis tool that is fast enough to be used at the suspension concept design stage.
Later on the assembly of all parts and mono spring. Full vehicle version also includes push rod and pull rod springs for double a arm suspension. Instead, theres a revolving cycle, with ideas being dropped and readopted over the years. Susprog3d suspension by design is a complete software package enabling the design. Pdf design and modeling of pull rod and push rod suspension. The design of the spring, damper, rocker arms and push rod was done by. If the goal is to race the car, then additional safety elements roll bar, roll structure may be. Optimumkinematics developed by optimumg engineers is a suspension and design analysis software. The use of the software served as a valuable tool in the selection of the proper metal alloy, and the geometry of each part. Design starts with the estimation of wheel travel, motion ratio and load on the springs from the wheels. In this episode, i summarize the design of the suspension. Generally, in race a car, double wishbone suspension with either pullrod or.