Once you've got PAS scrub radius is a detail. Caster angle and mechanical trail Caster is defined as the angle between the steering axis and the wheel centerline extending perpendicular from the contact patch, viewed perpendicular to the side view (vertical longitudinal plane). scrub radius, mechanical trail etc. This prototype is set to go on full production and is marketed towards the average weekend racer. So is judging! Setup optimization for the FSAE car MG07.12 Wheel loads estimate of a 125cc racing kart through on-track data acquisitions and numerical analyses Multibody analysis of the Formula SAE car MG0712 You can build a 136kg (300 lb) car with very narrow, high pressure tires, at zero scrub radius, with zero KPI, and zero caster, lots of steering ratio, and the steering input force will be very small indeed, maybe as … IRS have a scrub radius. In order to be deemed acceptable given the car’s restraints and the o Have peak loads been determined and designed for? The choice of these parameters should be based on how the vehicle is expected to perform. The concept of FSAE is that each collegiate chapter assumes the role of a fictitious company who is set on building a prototype formula style race car. ... the brake rotor is on the inside of the upright also helps to minimize the scrub radius on our tire. The larger the distance, the more effort is required to turn the wheel, as the tire has to “scrub” slightly to turn around the kingpin … widen the track, and b.) I used the tire-calculator at Wheel-Size.com to compare the oem set up, (which assumed the oem set up had a zero scrub radius) to the new rims and tires and it calculated the new scrub radius to be positive 21/32″ scrub radius which is approximately 5/8″ or 16.67mm. Scrub radius It is the distance between centre point of contact patch and point where the steering axis cut the ground, the fundamental reason to take scrub radius is to feel the ride on steering wheel, but it has a problem regarding the large scrub radius will tends to increase the wear of tyre, hence FSAE Design Event Scoring (Some Insight into the Process) The first thing to understand is that the design events are scored according to the criteria. This flaw demonstrates the importance of correct suspension parameters in the handling ability of the car. The upright was designed with minimal weight in … By visualizing the attitude of the car in a corner, the Beyond steering feel, I'm suggesting that having the center of the scrub radius inboard of the KP axis (negative-scrub) or near coincident to the KP axis (zero-scrub) will provide the rumored ride height drop while turning the wheels. These are the people that make the Rinehart PM100 motor controller that is well regarded in FSAE. In previous FSAE events from our college, the suspension design lacked in a solid methodology that will require time and resources. DESIGN While designing, the major factor is the type of geometry to be used for the steering system. INTRODUCTION: Formula Student India-International Level Event, also known as FS-IND is a design competition which follows the standards of the prestigious Formula SAE/Formula … Nick Butler, Grayden Elegante, Andre Romero, Spence Tan, Joel Williams. Figure 8 - Diagram illustrating KPI and scrub radius 2 While caster, KPI, scrub radius, and mechanical trail are usually fixed once the suspension is designed, toe can be adjusted to add or remove straight line stabilizing effects. FSAE Design Event Scoring (Some Insight into the Process) The design and developmental process of a FSAE car is a complex process. ... Scrub Radius & kingpin inclination. = The objective of this senior project is to design and optimize the suspension for FSAE and develop a process that future teams can follow. Suspension The first step to designing the suspension is picking out the ideal set up. This paper also gives us information about various load transfers under breaking, acceleration & impacts. The design is weighed ... Scrub radius Toe angle . Scrub radius is the distance from the centerline of the tire/wheel to where the kingpin line intersects with the road surface. Rajendra Mane College SAE Team, … You might say “That is a matter o f course! If I was designing an FSAE car, I'd just get a rack with more travel, and run a higher steering ratio (ie, less handwheel torque). Normal steering operating torque / forces depend on a number of variables. Rajendra Mane College SAE Team, MH08 Racing [2] give formulas for load transfer, breaking force & torque. caster trail, scrub radius and spring motion ratio, basically need to meet the overall vehicle targets. Furthermore, the kinematics of the suspension, such as roll centre height, track gain, camber gain, caster gain, Ackermann change with steering angle, roll steer and bump steer, also need to be verified. Using new research and analysis Scrub Radius. Part 2: https://youtu.be/oh535De4hKgSprings and Anti-roll bar video: https://youtu.be/NFGkZNrNTIE Recently I realized that changing the wheel offsets (or using spacers) to adjust the track width affects the scrub radius (a.k.a. The kingpin axis is the line between the upper and lower ball joints of the hub. Although many metrics and details are reviewed ... king pin inclination scrub radius, bump steer, and other geometry/kinematics? Looks like it'll have the power of the PM150 but it'll be smaller and lighter than the PM100. ... SAI and scrub radius. II. A negative scrub radius is suitable for vehicles with high power engine and a positive scrub radius offset for small power engines. Each graph represents an effect that will be experienced during various driving events, such as roll, heave, or turning. Mark Mark: "Bad Ast" Astro Van. Keywords: KPI, Camber, Caster, Scrub Radius, Roll Centre, Instantaneous Centre. Major Component – Wheel Upright. Upright functions: • Connecting hub for brakes, wheel bearings and A-arms • Allows wheels to move and steer through suspension travel It could be positive, negative or zero. bias the lateral weight distribution. Even solid axles have a scrub radius, it's just not really taken into account because it is moot. Budget Materials Cost = $322 Aluminum, Steel, Chromoly Tubing Parts Cost = $550 Bearings, Rod Ends, Spherical Joints, hardware Miscellaneous Costs = $100 Manufacturing Cost = ~$0.00 All fabricating was done by team in FSAE shop and student shop at no charge Total Cost = $972 Project Management The design of each component in the suspension assembly have been completed and optimized. Formula SAE is a student design competition organized by the SAE International. Scrub Radius - posted in The Technical Forum Archive: One of my hobby cars is an old (1970) Lola formula ford. Figure Ten: Scrub Radius vs. Motion Formula SAE Hybrid Team 10. The only useful thing it does is help the driver to detect pull under braking, which may indicate he's on a split mu. Ive been experimenting with wheel offsets to a.) 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