Is a hydrogen fuel cell car better in terms of emissions better or an electric car

The common thing in operation of electric car and hydrogen fuel cell car is the absence of a internal combustion engine that is used to drive a conventional vehicle. A hydrogen fuel cell car is also a kind of electric car. It runs also on an electric motor, but instead of a battery, a hydrogen fuel cell car has contains a hydrogen fuel cell that takes hydrogen and generates electricity from it while the car is running.

The electric and hydrogen fuel cell cars doesn't pollute the atmosphere as no fossil fuels are burnt in its operation. These are therefore referred as very green form of transportation.The actual fact is that these vehicles don't produce pollution at the tailpipe. But as we all know that electricity and hydrogen is produced
by some process in the power generation industry that also uses fossil fuels. The majority of the power is generated using fossil fuel sources. This will cause the same amount of pollution that is to be avoided by using
an electric car to avoid fossil fuels. The hydrogen for the fuel cell vehicle will most likely be produced in the future by electrolysis, which involves passing electricity through water. And that electricity will come from the same potentially polluting sources as the electricity used to charge the electric car's batteries.

To make electric cars and hydrogen fuel cell cars non-polluting forms of transportation requires to move away from methods of producing electricity that burn fossil fuels. Instead of burning coal to generate electricity, we'll need to concentrate on environmentally clean methods like hydropower, solar power, wind power and nuclear power, which produce little or no polluting emissions. When the day comes that most of our electricity comes from these sources, the electric car and the hydrogen fuel cell car will both be nearly perfect forms of green, non-polluting transportation.

Why is Toyota Recalling millions of car manufactured after 2012 ?

The reason for recalling millions of cars by Toyota is the malfunctioning of the airbags system accidentally due to spider webs due to short circuiting that can cause the drivers to lose control and face a severe accident.
The basic problem is identified in the air conditioning condenser unit housing, which can get warm and is damp. Such an environment is ideal for spider habitat. The sticky webs developed by spiders could cause a blockage,the blockage causes water to drip down into the airbag control module, which short circuits and can lead to a worrying warning light to display on the dashboard, or more seriously, cause the airbag to inflate suddenly as well as cut the power steering of the car.Toyota has also warned that there is even a risk of complete loss of power steering.

Toyota is also sort out a solution of the problem that can be done by the owners of the vehicles and also the dealers. They simply need to apply sealant and install a cover to the air conditioning condenser unit housing seam located above the airbag control module.Toyota has recalled Camrys, Venzas and Avalons that were manufactured after 2012.

What is a pneumatic tire? What are the major components of pneumatic tire?

A tire is a round shape rubber that is used to cover the metallic or alloy rim of the wheel. Its purpose is to protect the rim and to improve the performance of the wheel by providing traction between the vehicle and road. It also acts as a cushion to absorb the bumpy parts of the roads.

In the past the tires were simply bands of metal that were fixed around the wooden wheels to prevent the wear the tear of the wheels. After the development of rubber the tires were made up by them but they were solid tires that cannot be filled with air directly. Rubber tubes were inserted to keep them round. Today the modern tires also known as pneumatic tires are made up from synthetic rubber, natural rubber, fabric, wire and other chemical compounds. There are two main portions of these modern pneumatic tires first is the tread that is used to provide traction to the vehicle while other is the body that is a containment for compressed air. The main components of the pneumatic tire is explained below:

Tread

The tread is the part of the tire that comes in contact with the road surface. The tread is a thick rubber, or rubber/composite compound formulated to provide an appropriate level of traction that does not wear away too quickly. Treads are often designed to meet specific product marketing positions. High performance tires have small void ratios to provide more rubber in contact with the road for higher traction, but may be compounded with softer rubber that provides better traction, but wears quickly.

Tread lug

Tread lugs provide the contact surface necessary to provide traction. As the tread lug enters the road contact area, or footprint, it is compressed. As it rotates through the footprint it is deformed circumferentially. As it exits the footprint, it recovers to its original shape.

Tread void

Tread voids provide space for the lug to flex and deform as it enters and exits the footprint. Voids also provide channels for rainwater, mud, and snow to be channeled away from the footprint. The void ratio is the void area of the tire divided by the entire tread area. Low void areas have high contact area and therefore higher traction on clean, dry pavement.

Rain groove

The rain groove is a design element of the tread pattern specifically arranged to channel water away from the footprint.

Sipe

Tread lugs often feature small narrow voids, or sipes, that improve the flexibility of the lug to deform as it traverses the footprint area. This reduces shear stress in the lug and reduces heat build up.

Wear bar

Wear bars (or wear indicators) are raised features located at the bottom of the tread grooves that indicate the tire has reached its wear limit.

Bead

The bead is that part of the tire that contacts the rim on the wheel. The bead is typically reinforced with steel wire and compounded of high strength, low flexibility rubber. The bead seats tightly against the two rims on the wheel to ensure that a tubeless tire holds air without leakage. The bead fit is tight to ensure the tire does not shift circumferentially as the wheel rotates. The width of the rim in relationship to the tire is a factor in the handling characteristics of an automobile, because the rim supports the tire's profile.

Sidewall

Uneven sidewall wear, down to fabric plies, due to significant under-inflation. The sidewall is that part of the tire that bridges between the tread and bead. The sidewall is largely rubber but reinforced with fabric or steel cords that provide for tensile strength and flexibility. The sidewall contains air pressure and transmits the torque applied by the drive axle to the tread to create traction but supports little of the weight of the vehicle, as is clear from the total collapse of the tire when punctured. 

Shoulder

The shoulder is that part of the tire at the edge of the tread as it makes transition to the sidewall.

Ply

Plies are layers of relatively inextensible cords embedded in the rubber to hold its shape by preventing the rubber from stretching in response to the internal pressure. The orientations of the plies play a large role in the performance of the tire and is one of the main ways that tires are categorized.

What is a Hybrid car ? What advantages it can provide ?

The price hike of gasoline has motivated the car industries to come up with technology to overcome this price hike and add an advantage to their products. This advantage is a guarantee for the companies to raise the sale of their car. Hybrid car is the outcome of such a concept it can give upto 20 to 30 miles per gallon attional to the standard vehicle.In addition to the extra mileage it also helps in controlled emission that also aids in less pollution of the earth's atmosphere. 

 

A hybrid vehicle uses two or more different power sources to drive the vehicle. There are various types of hybrid vehicles but the most common vehicle today is HEVs. HEVs stands for Hybrid Electric Vehicles. In HEVs the internal combustion engine and electric motors are used to drive the vehicle.

A hybrid car is an attempt to gather the advantages of an electric car and a gasoline car. An electric car is pollution free and gives good mileage but the speed of the car is quite less. A hybrid vehicle attempts to significantly increase the mileage and reduce the emissions of a gas-powered car while overcoming the shortcomings of an electric car.A gasoline car meets these requirements but produces a relatively large amount of pollution and generally gets poor gas mileage. An electric car, however, produces almost no pollution, but it can only go 50 to 100 miles (80 to 161 km) between charges. And the problem has been that the electric car is very slow and inconvenient to recharge.

What is function of hand brake or parking brake in car?

Parking brake is also called hand brake, emergency brake or e-brake used to keep the vehicle standing mostly when it is parked. It is frequently used to prevent a vehicle from rolling back when the driver needs both feet to operate the clutch and accelerator.

The parking brake is made up of a series of steel cables that run from the rear brakes to a pedal or lever by the seat of the driver. When the driver initiates the brake, the cables pull rigid, carrying the brake pads into contact with the surface of the brake and stopping the car or preventing it from moving. Because the cables are attached to a ratcheting lever or pedal, when the driver removes the hand or foot used to activate the brake, it will still hold. In order to remove the brake, the driver needs to press a release button on hand brake and lower the lever.

Although, this brake is attached to the regular brakes of the car but it is independent of the hydraulic braking system connected to the brake pedal. In an emergency situation where the hydraulic brakes fail, the driver may still be able to stop the car using the emergency brake. It is recommended that a driver downshift before applying the emergency brake, as this will slow the car significantly, and reduce the grabbing feeling that accompanies high speed use of the emergency brake. In addition to being more comfortable for driver and passengers, this is also a safety measure, as if the car is traveling at a high rate of speed, it can fishtail or spin out when the emergency brake is applied.

When parking a car, it is important to set the parking brake, so that if the car slips into gear, it will not roll. In addition, drivers who are parking on a hill facing downhill should turn their wheels toward the curb or side of the road, so that if the brake slips, the car will roll off the road, rather than into it. When facing uphill with a curb present, the wheels should face into the street, so that the car will roll back slightly and bump into the curb if it rolls. If there is not a curb, the wheels should face towards the side of the road.

What is a self driven car? What level of autonomy is present in these types of cars?

Various automobile manufacturers are working on the concept of self driven car. The development in technology and computers has allowed such a dream to come true. Mercedes Benz has claimed that it will market its self driven car by 2020. Mercedes version of self driven car is said to be able to drive completely in all situations but still the controls can be diverted towards the driver in cases of emergency. It will be equipped with the option that the driver could take control of the vehicle whenever he wants to like for example dealing with traffic signal lights. Mercedes is the pioneer company to demonstrate autonomous driving practically by its car in rural and urban traffic.

Research is also being carried out in Oxford University with Nissan to create autonomous cars that can drive independently sensing the details of the roads like humans do. The cameras and lasers are placed in the chassis of the car to capture the 3D environment of the road for its storage in the computer for future guidance. The stored routes can be used for autonomous driving in future. Therefore the car remembers the routes to reach different places like human mind does. To avoid collision and accidents a laser scanner is used to scan 164ft ahead 13 times per second for obstacles in an 85 degrees field of view. The signal from the laser sensor is passed on to the control system of the car to stop the car if an obstacle is detected. If the driver sees some delay of malfunctioning he can get control of the car by pressing the brake pedal.