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A go kart with front wheel brakes has a stub-axle (fixed) that attaches ...
please solve this
A go kart with front wheel brakes has a stub-axle (fixed) that attaches the front wheels and brakes to the go kart via two bearings, as illustrated by the schematic in Figure 2. The race-ready go kart weighs 80kg and the driver weighs 75kg with all necessary driver safety equipment. The front wheels have a rolling diameter of 270mm, where the tyres have a braking friction coefficient of 1.8 and a cornering friction coefficient of 1.6. Notably the centre of the tyre contact patch is 20mm from the nearest bearing (see Figure 2). The bearing spacing is 75mm. The go kart typically drives around tracks with a 2km lap length, where the tracks can be divided into three segments; namely 50% straights, 35% corners and 15% braking zones. Assume there is equal weight distribution across all four wheels and there is no weight transfer during driving. The inner bearing (A) is SKF 61905 and the outer bearing (B) is SKF W 61905 deep groove ball bearings. With a confidence of 99.9%, calculate the number of laps the qo-kart can complete until bearing failure (and specify which bearing fails), where the average speed during straights is 90kmh, corners 50kmh and braking 70kmh. Due to impacts with kerbs and competitor, the application factor during straights, corners and braking is 1.1,1.4 and 1.2 , respectively. Please read the notes at the end of the assignment question sheet. The facts and numbers used in this problem are purely fictional and do not relate to the go kart illustrated in Figure 1.
Notes and Assumptions: I. Please include full working out for all the calculations II. Assume that the wheel friction loads act at the centre of the tyre width III. Assume that the tyre contact patch is directly below the axle IV. Assume there is no weight transfer during cornering or braking V. Assume the cornering loads are resisted by the outside wheel during cornering VI. Carefully note the bearing spacers and how they assist bearing force reactions VII. The axle does not rotate and it is attached to the go-kart at the axle fixing.
We need to calculate the loads on the bearings during braking.The weight on the front wheels can be calculated as:WEIGHT OF FRONT WHEELSTotal weight Weight on front wheels
BREAKING FORCEThe braking force can be calculated as:Braking force
LOAD ON BERAINGSThe load on each bearing can be calculated using the following formula:Load on bearing
WEIGHT OF FRONT WHEELS = 77.5 KG, Braking force = 1328N, Load on bearing = 355N