Table of Contents
How do I calculate my ride frequency?
f = 1/(2π)√(K/M)
- 0.5-1.0Hz Passenger cars, typical OEM.
- 1.0-1.5Hz Typical lowering springs.
- 1.5-2.0Hz Rally Cars.
- 1.5-2.5Hz Non-Aero racecars, moderate downforce Formula cars.
- 2.5-3.5Hz Moderate downforce racecars with up to 50\% total weight in max downforce capability.
What is wheel rate and spring rate?
Wheel Rate is basically the Spring Rate but measured at the wheel instead of the where the spring attaches to the linkage. It is basically the Spring Rate multiplied by the motion ratio squared. The motion ratio is the ratio between how much the spring is compressed compared to how much the wheel is actually moved.
What is the difference between roll rate and roll stiffness?
When cornering, the sprung mass of the car will roll by an amount , the roll angle. This is reacted by the roll stiffness (or roll rate), , of the car. Roll stiffness is defined as the resistance moment generated per unit of roll angle of the sprung mass, and it has SI units of Nm/rad.
What is spring rate?
Spring rate refers to the amount of weight that is needed to compress a spring one inch. If the rate of the spring is linear, its rate is not affected by the load that is put on the spring. For example, say you have a 200 lb. per inch spring – it will compress 1” when a 200 lb. load is placed onto the spring.
What is wheel hop frequency?
Wheel hop frequencies are typically in the 9-15Hz range, which always seems to coincide with powertrain vibration modes and, in turn, exhaust system and perhaps subframe modes. The correct choice of tire is a start, but being able to damp wheel hop effectively is vital, so a well-tuned damper is essential.
How does roll rate affect handling?
Roll rates determine the change in tyre normal force side to side for a given applied torque to the chassis or a given amount of chassis roll. One of the main purposes of suspension is to generate as much grip as possible from the tyres in order to make the car go as fast as possible.
Is higher spring rate better?
You might think the higher spring rate would react faster, but in reality, the lower spring rate will contact the ground first, and thus allows for more grip. With a lower spring rate, the force pressing the tire down remains higher longer relative to the amount of travel it has, so it contacts the ground much sooner.
What is the suspension system of Baja vehicles?
The suspension system of BAJA vehicle is to absorb vibration due to irregularities of road conditions maneuvering.that require greater stiffness and tough/rigid body. Greater stiffness creates fatigue to the driver. So springing action will be the major factor behind designing.
What are the Baja SAE rules for 2014?
The 2014 Baja SAE competition underwent rule changes, regarding the specifications of the frame (Engineers, 2014). Page ten of the rules specifies that the vehicle must accommodate a male up to the 95thpercentile, 186.7cm (6ft 1.5in) tall, 102kg (225 lbs), and an erect sitting height of 97cm (38.25in).
What is the Mini Baja East?
(“History of Mini Baja East,”) The purpose of the MQP was to design and manufacture a Baja SAE vehicle utilizing four wheel drive by the end of the 2014-2015 academic year for the SAE WPI collegiate chapter.
What is the SAE BAJA MQP?
The purpose of the 2014-15 Society of Automotive Engineers (SAE) Baja MQP was to design, develop, and manufacture a vehicle within the specifications of the SAE Baja Competition in order to enter a future competition. The chassis inherited from the 2013-14 SAE Baja MQP was utilized as a framework that the new designs had to integrate within.