Minimum mechanical requirements - Braking

Braking system makes an important mechanical entity to any automobile. An excellent braking system is the most important safety feature of any land vehicle. The main requirement of the vehicle’s braking system is that it must be capable of locking all wheels on a dry surface. Ease of manufacturability, performance and simplicity are a few important criteria that are to be considered for the selection of the braking system. The two main types of braking systems under consideration in this report are Drum and Disc brakes. In case of drum braking there is a high possibility of mud and debris to gather in the space between the shoe and the drum. Same problem is faced in mechanical disc brakes, but not in hydraulic disc brakes. Hydraulic brakes are found to be suitable for all type of terrain. Since, drum brakes are of more cost and they are heavier in weight which greatly increases the weight of solar car we can eliminate it. On the other hand, using hydraulic brakes can be an asset as it is cheap and it is readily available but the drawback was using this system the overall weight of the solar car is increased which makes it harder for the motor (linked to battery to solar panels) to run the car. The discs of brakes are made of paralytic grey cast iron. The material is cheap and has good anti-wear properties. Cast steel discs have also been employed in some cases, which wear even less and provide higher coefficient of friction; yet the big drawback in its case is the less uniform frictional behaviour. Two types of discs have been employed in various makes of disc brakes, i.e. the solid or the ventilated type. Disadvantages of ventilated type discs include usual thickness and heavier than solid discs, In case of severe braking conditions, they are liable to wrap, accumulation of dirt in the vents, which affects cooling, resulting in wheel imbalance, Expensive, Difficult to turn. Turning produces vibrations which reduces the life of the disc. Any of these make no much difference on the solar vehicle mentioned in this report as its overweight cannot go beyond 450kgs to 500kgs. Although in the practical version of the solar vehicle done through this report hydraulic drum brakes are used for the front axle and mechanical disc brakes are used for rear axle for experimentation  it is advisable to opt for hydraulic disc brakes for both the front and back axles as they are economical and reliable.