Introduction
The purpose of this technical report is to communicate the results of the Pneumatic Tyre Characteristics laboratory by investigating the effect of cornering force on slip angle. The technical report is presented to the academic staff of the Engineering Systems Department at the Royal Military College of Science, Shrivenham. It is assumed that the reader is fully familiar with the experiment and with the equipment on which it is preformed.
Experimental Conditions
• For this particular experiment the gain of the output for the strain gauges are set to 1 as 0 to 8 degrees slip angle is been measured. If smaller angles are measured a larger gain may be required.
• The total displacement of the trolley that runs along the track is approximately 2.17 meters. However, this may slightly vary in the results, especially with higher slip angles due to the reaction force acting on the reversible hydraulic motor that drives the track. For consistency the corresponding point for each distance is taken in the results.
• The current details and condition of the tested tyre are given.
- Manufacture: Avon.
- Dimension: 710 / 22.0 – 13.
- Condition: Generally worn all around with patches of the tyre (approximately 60mm in diameter) in worse condition on the inside of the wheel.
• The tyre was tested at 14, 16 and 18 psi pressure. For each test at each angle increment the air valve is pointing downwards purely for consistency as the tyres circumference may vary. The increments for each test are as follows.
- 0 – 5 degrees in 0.25 degree increments.
- 5 – 8 degrees in 0.5 degree increments.
• The experimental equipment is set to output 1000 points of displacement and side force. The computer capture rate is set to 50Hz and a total run time of 20sec
• Final experimental conditions that should be mentioned include:
- Before the conduction of the experiment the camber of the wheel should be checked and adjusted to zero degrees.
- The track is manufactured to have a sand paper surface. This is important to exert a sufficient side force on the tyre and is in good condition.
- For each experiment, initially slip pads are used under the wheel as the mechanical mechanism used to apply the vertical force is applied at a radius and therefore would give an unwanted offset.
- A constant vertical load of 1.5kN is applied to the tyre. This load is kept consistent by a mechanism which includes a beam and counter balance weights.
A connecting rod subjected to an axial load F may buckle with x-axis as neutral axis in the plane of motion of the connecting rod, {or} y-axis is a neutral axis. The connecting rod is considered like both ends hinged for buckling about x axis and both ends fixed for buckling about y-axis. A connecting rod should be equally strong in buckling about either axis [8].
Tire manufacturers sometimes publish a coefficient of rolling friction (CRF) for their tires. You can use this number to calculate how much force it takes to push a tire down the road. The CRF has nothing to do with how much traction the tire has; it is used to calculate the amount of drag or rolling resistance caused by the tires. The CRF is just like any other coefficient of friction: The force required to overcome the friction is equal to the CRF multiplied by the weight on the tire. This table lists typical CRFs for several different types of wheels.
In the future, the experiment can be improved by making sure that changes above, if required, are done before the first trial of the first run starts. Another problem was that the 3-step pulley moved slightly every time a trial was conducted. This could be prevented for the future labs by have a 3-step pulley that more resistible to movement. With these improvements, future laboratory might get more accurate results.
Tires are thrown from tires because the centrifugal force expels snow, rocks, and other foreign objects.
The file labeled “Newton’s 2nd Law” is to be opened. The cart’s mass along with the attachment of the sensor and the accelerometer are to be measured and recorded. Being carefully verified in order, the track is leveled and the Force Sensor is set to 10N and connected to...
Wind tunnels can be divided into three categories according to the range of air speed. In the low air speed section of the wind tunnel where air speeds range from (0.1 – 1.5) m/s, has a test section with large cross-sectional area, is adopted to generate a low-speed environment for calibration of anemometers [3]. Occasionally, the low-speed wind tunnel contains ...
... this experiment, the shape of the wake behind the cylinder was determined and the water tunnel was calibrated. The conclusions are listed below:
My hypothesis is the higher we put the ramp the more forces will act upon the car giving less friction meaning the car will accelerate more traveling to a further distance.
Mechanical Engineering 130.2 (2008): 6 - 7. Academic Search Complete. Web. The Web. The Web.
Possible sources of error in this experiment include the inaccuracy of measurements, as correct measurements are vital for the experiment.
Regardless if one is riding on hard solid pavement or soft dirt, the same basics of cont...
Gilles, J. (2005). Automotive chassis: Brakes, steering & suspension. Santa Barbara, California: Thomson Delmar Learning.
When an attempt is made to push a car from rest on concrete, the coefficient of static friction is so high (almost 1). However, once the car starts to move, it is easier to keep pushing it because the coefficient of kinetic friction is lower (almost 0.8). Similarly, when an attempt is made to push a car from rest on a wet road, the coefficient of static friction is not that high (almost 0.6). However, once the car starts to move, it is easier to keep pushing it because the coefficient of kinetic friction on wet road is lower (almost 0.4). Furthermore, when an attempt is made to push a car from rest on snow, the coefficient of static friction is lower (almost 0.3). However, once the car starts to move, it is easier to keep pushing it because the coefficient of kinetic friction on snow is lower (almost
Theoretical value of I was greater than experimental by 0.0317 kgm^2. The experimental value of I was calculated dividing Torque by angular acceleration thus the Torque should have been larger or angular acceleration smaller.
Then the ITS test is performed on the sample at 77°F (25°C) at a loading rate of 2in/min.