A steering wheel (also called a driving wheel or hand wheel) is a type of steering control in vehicles and vessels (ships and boats).
Steering wheels are used in most modern land vehicles, including all mass-production automobiles as well as light and heavy trucks. The steering wheel is the part of the steering system that is manipulated by the driver; the rest of the steering system responds to such driver inputs. This can be through direct mechanical contact as in recirculating ball or rack and pinion steering gears, without or with the assistance of hydraulic power steering, HPS, or as in some modern production cars with the assistance of computer controlled motors, known as Electric Power Steering. With the introduction of federal vehicle regulation in the United States in 1968, FMVSS 114 required the impairment of steering wheel rotation (or transmission locked in "park") to hinder motor vehicle theft; in most vehicles this is accomplished when the ignition key is removed from the ignition lock. See steering lock.
The terms right-hand traffic and left-hand traffic refer to regulations requiring all bidirectional traffic to keep either to the right or the left side of the road, respectively. This is so fundamental to traffic flow that it is sometimes referred to as the rule of the road. This basic rule improves traffic flow and reduces the risk of head-on collisions. Today, about 60% of the world's population live in countries with right-hand traffic and 40% in countries with left-hand traffic. About 70% of the world's total road distance carries traffic on the right and 30% on the left.
In automotive design, the automobile layout describes where on the vehicle the engine and drive wheels are found. Many different combinations of engine location and driven wheels are found in practice, and the location of each is dependent on the application for which the vehicle will be used. Factors influencing the design choice include cost, complexity, reliability, packaging (location and size of the passenger compartment and boot), weight distribution, and the vehicle's intended handling characteristics.
Layouts can roughly be divided into two categories: front- or rear-wheel drive. Four-wheel-drive vehicles may take on the characteristics of either, depending on how power is distributed to the wheels.
Torque steering is the influence of engine torque on the steering, especially in front-wheel drive vehicles with transversely mounted engines. For example, during heavy acceleration the steering may pull to one side, which may be disturbing to the driver. The effect is manifested either as a tugging sensation in the steering wheel, or a veering of the vehicle from the intended path. Torque steer is directly related to differences in the forces in the contact patches of the left and right drive wheels. The effect becomes more evident when high torques are applied to the drive wheels either because of low transmission gearing, high engine torque, or some combination of the two. Torque steering is distinct from steering kickback.
Human–computer interaction (HCI) involves the study, planning, and design of the interaction between people (users) and computers. It is often regarded as the intersection of computer science, behavioral sciences, design and several other fields of study. The term was popularized by Card, Moran, and Newell in their seminal 1983 book, The Psychology of Human-Computer Interaction, although the authors first used the term in 1980, and the first known use was in 1975. The term connotes that, unlike other tools with only limited uses (such as a hammer, useful for driving nails, but not much else), a computer has many affordances for use and this takes place in an open-ended dialog between the user and the computer.
Because human–computer interaction studies a human and a machine in conjunction, it draws from supporting knowledge on both the machine and the human side. On the machine side, techniques in computer graphics, operating systems, programming languages, and development environments are relevant. On the human side, communication theory, graphic and industrial design disciplines, linguistics, social sciences, cognitive psychology, and human factors such as computer user satisfaction are relevant. Engineering and design methods are also relevant. Due to the multidisciplinary nature of HCI, people with different backgrounds contribute to its success. HCI is also sometimes referred to as man–machine interaction (MMI) or computer–human interaction (CHI).