Self-Driving Cars Gain Backing of u.S. Regulators
By Jeremy Hsu
1. U.S. federal officials apparently like what they see in self-driving cars: their potential to operate more safely and fuel-efficiently than the vast majority of human drivers. These huge benefits prompted the National Highway Traffic Safety Administration (NHTSA ) to give a cautious green light to the autonomous driving projects of automakers and technology companies. The NHTSA is not alone. Nevada, Florida, California and the District of Columbia have already begun setting ground rules for the operation of self-driving cars.
2. Self-driving cars offer more than added convenience during a driver's work commute. Widespread use of fully autonomous vehicles could slash annual costs related to road accidents by $488 billion and save $158 billion in fuel costs as part of $1.3 trillion in total savings for the U.S., according to a recent Morgan Stanley study. Get enough of them on the road, and you might even reduce traffic jams or end highway congestion.
3. Google's self-driving car tests have sparked the public's interest and excitement about the technology in recent years. But the Internet giant is still moving cautiously in figuring out how to market the technology and deal with related challenges. Ron Medford, director of safety for Google's autonomous car project, told that the auto industry must prepare to deal with fallout from accidents involving autonomous cars.
4. The automakers anticipate a gradual rollout of driver assistance technologies capable of handling stop-and-go traffic, parallel parking or long stretches of highway driving. Car events such as the Frankfurt Motor Show have showcased even more advanced technologies such as Bosch's emergency autonomous braking system and Ford's obstacle avoidance system that automatically steers around obstacles in the road.
5. But self-driving cars won't hit the road anytime soon, except for test drives. Still, major automakers such as Nissan have suggested they could have autonomous cars ready for dealerships by 2020. The time is needed to road-test each technology before unveiling the full autonomous car package.
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Text 4c. Laser Welding in the Automotive Industry Welding of Automotive Components
Read the following text and make its summary.
The applications of laser in the manufacture of components cover engine parts, transmission parts, alternators, solenoids, fuel injectors, fuel filters, air conditioning equipment and air bags. An example of a laser welded solenoid is shown in Fig. 1. and gear component is shown in Fig. 2. The attractions of laser welding for these applications are the ability to weld pre-machined precision components with restricted heat input and minimal distortion. This enables weight savings to be made through the use of thin walled assemblies and optimisation of the compactness of the component.
Fig. 6. CO 2 laser welded solenoid.
Fig. 7. CO 2 laser welding of gear component.
In industrial production, the advantages of the laser welding process have been established compared to alternatives such as electron beam welding. This is due mainly to the high productivity and small amount of down-time compared to vacuum based systems and the subsequent reduced manufacturing costs [3] . However, there is a need to spend a high amount of effort on component preparation and high precision of component handling and beam transmission is required. [4]
Most automotive manufacturers have invested heavily in CO 2 laser technology for these types of applications and most of the issues relating to the production of millions of components have been resolved. Developments have focused on expanding the range of material combinations which can be welded using lasers, including joining of cast irons to steels through the use of wire feed techniques and optimization of the procedures to harden components whilst avoiding problems with cracking due to high carbon levels in the weld zone.
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Exercise 13. Make reports on the following topics( See supplement p. … )
1. The benefits of laser welding in car design.
2. The laser welding of aluminum alloys.
3.An industrial impact of laser welding.
4. Types of welding in car design.
5. Chemical structure of metals and their response to welding.