The pneumatic tire or air-filled tire is composed of a core filled with airtight sealed pressurized air. Usually, a tread made with reinforced steel belting or other type of materials, seals this inner core and provides the contact part with the road.
As the pressure of the air inside the tire is greater than atmospheric air pressure, the tire remains inflated even with a vehicles' weight resting on it. The pressure of the air inside the tire provides resistance against forces which try to deform the tire. This gives the tire a slight degree of a cushioning effect as the tire hits bumps in the road. If you have ever taken a ride in an old-fashioned carriage which had wooden wheels, you understand how big of a difference a set of pneumatic tires makes.
Pneumatic tires also come with drawbacks. Highly dangerous applications or high-performance situations for instance, these tires can suffer a puncture and this will lead to a total failure. The consequence of a blowout at high speeds could lead to a dangerous car crash. Military planners must consider tires getting blown out by explosion shrapnel or shooting of guns. A vehicle crew's worst nightmare is becoming trapped in a fire zone due to all of their tires becoming flat. Airless tires obviously don't suffer from these issues and thus, in certain applications, might be more suitable.
Pneumatic tires have another problem involving variations in tire performance and air pressure. Lower tire pressure could create improved traction and increased comfort. This is because of the fact that tires flatten slightly and more tread is placed in contact with the road. The pressure of the air in the tire works to maintain the lateral stiffness of the tire as well as maintain the "up and down" stiffness. Hence, reduced air pressure enables the tires' sidewalls to flex. This leads to poor handling unfortunately. Within an airless tire, the stiffness in those two dimensions is independent.
Air pressure factors into other problems also. With regards to to maintaining proper air pressure, consumers are notoriously undependable. Improper air pressure within tires could result in very dangerous situations. It is very vital to note that pneumatic tires are also prone to temperature changes, which could be responsible for changing the internal pressure of the tire. It is important to consider the type of environments you would be requiring your machinery to operate in so that you could frequently inspect the tires and keep the machine as safe as possible.