So i took his interest and decided to do a thread and also make instill some info on suspension geometry. Software for designing and analyzing suspension systems and geometry. The options for entering your geometry specs include. The old model remains at the back of the drawing, you can use it as a guide when making adjustments to the layout or visually compare how the changes will perform when the suspension is in motion. Spec is software for tuning motorcycle suspension and chassis geometry. Abstract the paper explains design methodology and flow in a suspension is one of the most vital subsystems of an automobile. As such, it appears on your registry and it is accessed via the start menu. Easy and effective virtual prototyping of vehicle suspensions. Rear suspension geometry this is a software package that addressesthreelink suspensions and late model fourlink floaterstyle. Front suspension geometry thread chevy truckcar forum. Suspension geometry an overview sciencedirect topics. Aug 29, 2007 you cant calculate the suspension geometry from this info the loads will determine the area thickness cross section of the suspension arms necessary to carry the loads but suspenion geometry will always be chosen by the designer as the best compromise between tyre movement path of the tyre centre, camber change, bump steer if present. The classic version of the suspension geometry calculator.
Racewise provides the technical understanding of suspension and tire performance that racers must have in order to make no guesswork decisions. Figure 3 independant front suspension on the 2017 ford raptor frontend fued ifs vs. As a base point, in order to calculate the standard suspension geometry accurately, i used chris gibb. Design, analysis and optimization of suspension system for. Like dimensions of upper and lower a arms and knuckles and how can i cycle it on paper or solidworks. Another prime indicator, although it is one that could be misleading, is a low left front tire temperature. Afco rwfront suspension geometry software race wise. Greatercaster,greatercasterlead % when%cornering,% z a p z v v v p p u v z v v p x d z v v p. We are designing the front suspension, and will input data for the lh side. Rear suspension geometry this is a software package that addressesthreelink suspensions.
Allows steer, roll and bump or rebound suspension movements. Bump steer toe change in or out caused by a disparity between the geometry of the front suspension compared to the steering geometry. Jul 23, 2017 smitty describes the principles of suspension design. The front suspension geometry pro software requires the geometry to be specified by the coordinates of all the joints and pivots. This is the fifth in the video series developed for ucis racecar engineering program. Software for auto racing and high performance cars data acquisition systems new and used engineering services and live seminars on performance and racing technology all types of tech info on racecar engines, chassis and suspension setup for road. If it is rear then click it, and change it to front. The full installation zipped folder is a zipped folder, which has to be unzipped and installed. All types of tech info on racecar engines, chassis and suspension setup for road. Independent suspension with long travel and four wheel drive gives you a comfortable ride with the ability to absorb the bumps at speed. There is no doubt in the world of aftermarket tuning and club motorsport, that suspension geometry is one of the most overlooked factors.
The roll center calculator lets you input, view, save, analyze and compare either double a frame or mcpherson strut front suspension geometry. For windows 7, 8 and 10 with opengl see the faq for more. It is important for the suspension to keep the road. For the amateur car designer, there are many tools available today that make designing a car easier. How to find the roll center with this type of front suspension. Because obviously you will very rarely have a perfect parallelogram or any other normal 4sided shape in a suspension s geometry. Front and rear suspension analysis simulation software program. Engineering services and live seminars on performance and racing technology. Antisquat, antidive and antilift geometry which will be referred to as anti geometry when discussing them as a whole is a form of geometry at the front and rear wheels that alters and controls the amount that a car will compress the springs due to acceleration, deceleration or braking conditions. Suspension systems must support both road holdinghandling and ride quality, which are at odds with each other. Finding your center finding your front and rear roll center. Drawing templates, 3d cad, fea, cfd, suspension geometry. Combines photolike graphics with the power of highspeed computer intelligence to give you clear and fast improvements to your front suspension. You can also use this function to compare front and rear suspension although be careful as only the model at the front of the drawing is saved within the url.
Universal suspension geometry software race wise by afco. Susprog3d suspension by design is a complete software package. Free tools and software for race car, sports car and offroad vehicle design. Using chassissim to evaluate suspension geometry youtube. Suspension geometry part 1 camber, toe, caster, kpi. It is based on chapter 7 of the book chassis engineering by herb adams isbn 1557880557. Rear suspension geometry this is a software package that addressesthreelink suspensions and late. Smitty describes the principles of suspension design. Analyzes and helps you to correct camber curve, side scrub, bump steer, caster curve and foreaft suspension. Antipitch is the name given to a suspension geometry, front and rear that prevents pitch under braking. 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.
For windows 7, 8 and 10 with opengl see the faq for more details faq for more. Easily and effectively create vehicle suspension designs, that can be used to help make design decisions at the initial concept stage up to and including det. Front view suspension geometry calculatorsimulator. Stop guessing and start winning learn the facts of front suspension geometry with this informative cdrom computer software. Some software includes kinematic capabilities that simulate vehicle dynamics using the designed suspension. There is a roll center for the front suspension and rear suspension. The 4link calculator lets you input, view, save, analyze and compare your 4link rear suspension geometry. However the front suspension can also be integrated. Auto suspension design made easy lotus engineering suspension analysis lsa, the commercial version of software from lotus engineering in the u. 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. With this calculator you will see how bump and droop can affect camber.
The primary indicator of a left front not working is when we see that tire off the ground through the middle of the turns. The suspension calculator aims to help people who are building race cars perform suspension related calculations. Srt front suspension modeling in adams car duration. This 5minute video by mike higley provides an insight into the settings for front suspension and geometry for your racecar. The more antilift there is, the less the front will lift during acceleration, at a cost to traction and comfort. All chassis dimensions and specifications are editable. What is the best free cad software for racecar engineering. This approach is cumbersome for performing whatif calculations, because all the joint and pivot locations are interrelated by the relationships above. Autoware autoware inc front suspension geometry software. You enter heights above the ground and distance ahead of the front axle for up to 6 holes for all 4 brackets for your car, or any number of cars. No one can predict the perfect set up, even for a spec formula where much of the suspension is fixed by the rules.
Aftermarket components like yokes and linkages can be measured and input by the user. Design of three and four link suspensions for off road use. Take a look at performance trends calculators here. Now you can get all the racewise chassis school material in an easytouse software program for your home computer. The tuning of suspensions involves finding the right compromise. Any input would be appreciated and feel free to let me know anything youd like to share about designing a front suspension system, i am burning to learn about it. Design of the geometry of double wishbone suspension system along with design of spring plays a very important role in maintaining the stability of the vehicle. Please note that geometry control is not a system to improve manoeuvreabi1ity steering. Rear suspension geometry is your car loose and cross weight nor springs will fix the problem. Computesreports all critical front suspension factors like moment arm length and shockspring travel. The front end takes more hits and has less travel, it is more likely to suffer damage and wears faster than the rear when you are pushing hard. Performance trends offers a few different options, including a free trial.
In this tutorial danny nowlan the director of chassissim technologies outlines how you can use the analysis and simulation aspects of. Depending on the type of suspension, the roll center can be an actual pivot point or a virtual point in space and they dont necessarily lie along the center line of the vehicle. One of them is the pursuit of better handling, and that makes the front suspension an important focus. As you drag the mouse or the scroll bar, the car moves up and down in response. Or, maybe you are looking for a little more forward bite.
The two opel systems optimize the suspension geometry with. Car design tools for chassis, suspension, aerodynamics. Vehicle travel is simulated by dragging the image with the mouse or with a scroll bar. Racewise rwfront front suspension geometry software. At some point you will want to enter your own suspension geometry data or even just just view the current model in more detail. Susprog3d is the premier kinematic suspension design and analysis tool. First up is the proper design of a control arm suspension. Design, analysis and optimization of suspension system for an off road car. Vsusp no longer supports any version of internet explorer. From creating an accurate model of the car and every nut and bolt in it in 3d, to the design and simulation of critical aspects such as the chassis and suspension, software programs have become commonplace to amateur car design. The calculations vary from motion ratios, to spring stiffness, to wheel loads. It provides a way to isolate the chassis and driver from the shocking jolts that the tires experience going over anything but a glasssmooth surface. Suspension geometry part 1 camber, toe, caster, kpi, scrub radius sk8215. Pressing the edit button immediately switches to edit mode listing more details about the dimensions of the model and allowing you to alter the model by dragging any of the tether points.
In this episode, i summarize the design of the suspension. It provides a stable platform from which to control the vehicle. Front suspension geometry pro incredible, amazing and astonishing, you have to see it to believe it. A tire not in contact with the racing surface does no work. Zach messaged me about making a thread on the front suspension kits available for the nbs trucks to talk about pros and cons to each kit. It includes graphs and suggestions for changes to your geometry. My drawings are mostly all done, so im testing the front suspension layout as insurance.
I input genuine dims from an s2 seven, an elan, europa not so surprisngly they are not significantly different in geometry from each other or a lotus 7. Feb 20, 2017 front end geometry missouri state university engineering. The suspension on a vehicle serves multiple purposes. The upper arm is usually shorter to induce negative. Double wishbone suspension system it is popular as front suspension mostly used in rear wheel drive vehicles. Oct 14, 2015 suspension geometry software for purchase. Both versions of the software provide the same features. Because internet explorers maximum url length is shorter than other browsers, your project cannot be saved properly in this browser. Motospec has been designed for racing use, with a simple interface and clear outputs, to assist motorcycle tuners and race teams make quick and knowledgeable decisions. The front roll center is rarely at the same height as the rear roll center. This involves placing the force application points g and h on the centre of gravity. Hey how do you figuare out ifs geometry if i wanna fabricate a long travel front suspension. Cowlmounted steering boxes, however, should also be mentioned since the geometry can cause horrendous bumpsteer if there is a lot of suspension travel, though of course most rods have a.
This chapter will cover some basics and performance aspects of front suspension alignment, as well as separate components and complete front suspension. Camber matters optimizing track performance for strut. Basic suspension geometry this is a basic get you going tutorial, using the registered susprog3d software. Under acceleration, a low antidive geometry will cause the front end to lift and the suspension to extend which. Suspension systems with antidive values under 100% will cause the front suspension to compress under breaking, often called nosedive. There are a number of anti geometry features, with the main three known as. Antilift refers to the amount of builtin antilift built into the front suspension of frontallwheeldrive cars relies on drive torque. Here are a few terms youll need to be familiar with to understand the finer points of tuning a car with strut suspension. It is simplicity itself and a great place to start learning about suspension geometry. If you are on the market for a more indepth, customizable 4 link suspension calculator, you will likely need to purchase software.