 Issue 2: Fall 2004 : The Automotive IndustryModern Automobile Manufacturing
While the automobile is a commonly used product, it is an extremely complex and technologically sophisticated one. Manufacturing new cars requires state-of-the-art technological methods and processes. In addition, supplier industries of the automotive manufacturing industry, such as steel and other parts as well as electronic instrumentation, are vital in providing the necessary supplies and components for assembling motor vehicles.
To improve product quality and efficiency in production, automakers invest a large amount of time and money into developing and improving the manufacturing process, and rely heavily on research and technological innovation. Over the last 75 years, significant technological development has taken place, changing and reinventing how motor vehicles are produced.
Technology has increasingly altered the manufacturing process for motor vehicles. While cars are produced at faster rates, automakers must continue to balance increased productivity and efficiency with quality and innovation. Modern technologies used in advancing manufacturing for the automotive industry include:
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Over the last 25 years, automation technology has become an essential part of automobile assembly plants. A typical assembly plant uses several hundred robots to build and paint the vehicle frame. 2 While robotic technology continues to grow in assembly plants, the technology does have limitations, especially in performing more delicate tasks. The advent of Intelligent Assist Devices, in particular Cobots (Collaboratiave robots), aided in reducing ergonomic concerns, while also improving safety, quality and productivity. Cobots, developed by Northwestern University and General Motors Corporation, are designed to work in collaboration with human operators to move objects and perform physically demanding tasks on vehicle assembly lines.
Automobile manufacturing firms compete based on a set of established commercial practices which are conveyed in business and industrial engineering literature.3 These practices make up the process of automobile manufacturing, which are depicted in the following list of elements:
Elements of Automobile Manufacturing
In looking at trends in global automobile manufacturing, Japanese automakers have been leaders in stream-lined manufacturing process systems. These methods have been adopted by manufacturing plants worldwide. These efforts were pursued in order to increase productivity and product quality. U.S. and European automakers initially showed considerable gaps in manufacturing plant productivity, however the gap in productivity with Japanese automakers' assembly plants have been narrowed substantially in the last several years.
Research on Modern Automobile ManufacturingAkella, Prasad, and Peshkin, Michael. Cobots for the Automobile Assembly Line. IEEE International Conference on Robotics and Automation 1999.http://othello.mech.northwestern.edu/~peshkin/pubs/1999_CobotsAutomobileAssembly.pdf This paper describes the broad design principles for human-machine interaction in industrial settings. The creation and use of Cobots (Collaborative robots), were designed for assisting assembly line workers. The paper indicates that commercial use of these technologies in industrial settings are currently underway.Fine, Charles H., and St. Claire, Richard. The U.S. Automobile Manufacturing Industry. Meeting the Challenge: U.S. Industry Faces the 21st Century. Washington, D.C.: U.S. Department of Commerce Office of Technology Policy, 1996. http://www.mne.psu.edu/simpson/courses/me546/projects/auto_industry.pdf This report on the U.S. automobile manufacturing industry concentrates on the Big 3 firms (General Motors, Ford, DaimlerChrysler) and discusses the condition of the industry, product and production strategies, the importance of the supply chain, distribution and retailing, conclusions, and possible future directions.Landham, Ralf. The Future of the Automobile Industry: Challenge and Concepts for the 21st Century.Warrendale, PA: Society of Automotive Engineers, 2001. LC Call Number: HD9710.A2 Z8513 LC Catalog Record: 00045810 This updated edition examines issues currently facing the automotive industry. Fifteen contributions from consultants and other automotive industry professionals discuss factors such as emerging markets, globalization, technological innovation, environmental demands, and e-business, as well as offer approaches for meeting these challenges. Synopsis by Book News, Inc.Maxton, Graeme P. Time for a Model Change: Re-engineering the Global Automobile Industry. New York: Cambridge University Press, 2004. LC Call Number: HD9710.A2 M3863 2004 (in process as of November 2004) LC Catalog Record: 2004045634 Table of Contents Publisher Description This work examines the automotive industry, making recommendations for change and improved industry performance.Van Biesebroeck, Johannes. Measuring Productivity Dynamics with Endogenous Choice of Technology and Capacity Utilization: An Application to Automobile Assembly. Center for Economic Studies Working Paper. Washington, D.C.: Center for Economic Studies, U.S. Census Bureau, 2000. http://siepr.stanford.edu/publicationsprofile/619 This study examines North American and Japanese automobile assembly plants comparing production processes by utilizing a model that allows for heterogeneity in technology and productivity.Van Biesebroeck, Johannes. "The Effect of Technology Choice on Automobile Assembly Plant Productivity."The Economic and Social Review, Vol. 33, No. 1, Spring, 2002. This Paper examines the effects of technology on U.S. assembly plants productivity from 1963 to 1996, and evaluates the determinants off aggregate productivity growth. Automobile Technology & Innovation
The product life-cycle for automobiles continues to shorten due to competitive market pressures. Competitive market forces have caused automakers to dramatically redesign car models every four to five years.4
New technological developments have led to unique and innovative designs for future automobiles. Automobile manufacturers use the development of new technologies to enhance performance capability, as well as to create innovative designs. Alternative fuel technologies, such as electric hybrids and fuel cell cars, have received considerable attention, and demonstrate attempts to design vehicles that are more energy efficient and greatly reduce engine propulsion reliance upon fossil fuels.
Electric Powered Vehicles
The movement towards electric powered vehicles began as a result of the 1973 Oil Embargo, in which efforts were made to utilize electric battery technology to power engine propulsion. However, problems and limitations regarding driving range, speed and a very small market, all led to automakers GM, Ford, Honda and Toyota discontinuing their electric vehicle programs during the late 1990's.
Hybrid Powered Vehicles
Hybrid vehicles combine two or more sources of power, which are able to operate using a rechargeable battery and gasoline. Production of gas-electric hybrids signifies the first significant move away from total reliance on the internal-combustion engine in nearly a century.5
Hybrid vehicles are highly fuel efficient and presents the first major step toward fuel cell vehicles, according to industry specialists. Japanese automaker Toyota, is one of the auto industries leaders in hybrid vehicle research and production with its Prius model. General Motors, also involved in producing hybrid vehicles, will be introducing and mass producing its hybrid model by 2007.6 Most major automakers plan to introduce hybrid vehicles to the market within the next five years.
Fuel Cell Vehicles
Another automobile technology that is presently viewed as the latest catalyst in future automobile technology, is fuel cell powered vehicles, in particular hydrogen fuel cell powered engines. Fuel cell systems operate by compressing hydrogen made from natural gas and gasoline, which is then converted to hydrogen by on-board systems. 7
Automakers and suppliers worldwide are investing substantially in the development of fuel cell systems. General Motors (GM), Ford and DaimlerChrysler have invested billions of dollars in a collaborative project to develop hydrogen fuel cell technology. GM is perhaps the most active in investing, as well as researching and developing fuel cell technology. However, many industry specialists indicate that fuel cell technology will not be available on the commercial market until the next 10 to 15 years.
There are, however, problems associated with hydrogen fuel systems which consist of:
Many uncertainties remain regarding the development and use of hydrogen fuel cell technology, as well as addressing the major question on how to create a viable infrastructure that supports the use of fuel cell vehicles.
Advanced Product Design and Vehicle Operating Systems
Modern automobiles are increasingly relying upon more advanced electronics, computer, and wireless communication systems to assist drivers and enhance safety. These technologies replace mechanical systems that power, steer and brake the vehicle. Most vehicles have several computers, with high-end models having a half dozen or more that control functions, which range from shifting gears to operating GPS navigational systems.8
GM has introduced the Autonomy concept model, which uses hydrogen fuel cell technology that powers electric motors in each wheel. The vehicle uses a chassis and replaceable body, allowing greater flexibility and freedom in designing the interior. Internally, the vehicle operates without pedals or dashboard, using sophisticated computer and electronic systems to operate the vehicle.
Voice activation is another technology being developed for use in future vehicles. Voice activation systems are expected to operate internal climate controls, open doors, and respond to navigational request by the driver.
The next step in automobile electronic and communications technology is vehicle sensor technology. Sensor technologies use radar or laser technology to control systems that detect vehicles in front which then automatically slow down the vehicle. Companies are using sensor technology to serve as collision-avoidance systems that operate and control vehicle safety systems and on-board equipment.
Research on Automobile Technology & InnovationAuto Innovation. Auto Alliance Driving Innovation, Alliance of Automobile Manufactures.http://www.autoinnovation.com/ Automobile, Wikipedia Online Encyclopedia http://en.wikipedia.org/wiki/Automobile This website provides an general overview discussing the automobile. The contents includes the History, Innovation; Regulations and Safety; Renewable energy; Major subsystems; Related articles; and automobile images.Borroni-Bird, Christopher E. "Vehicle of Change." Scientific American, October 2002, Vol. 287 Issue 4. Discusses hydrogen fuel cell cars, and advantages of hydrogen fuel cell systems; Implications of hydrogen fuel cells for personal transportation and for the automotive industry business model; and discusses the new GM Autonomy design concept, and explains how the vehicle operates using fuel cell and other advanced technologies.Fairley, Peter. "Hybrids' Rising Sun." Technology Review, April 2004. http://www.technologyreview.com/ This article examines the development and production of hybrid vehicles, primarily looking at Toyota's pioneering efforts in being the leading industry producer hybrid cars with its Prius model. The article also discusses efforts by made by GM and other U.S. automakers to produce hybrid vehicles.Jerome, Marty. "Smart Cars." LookSmart.com-FindArticles, April 2001. http://www.findarticles.com/p/articles/mi_zdzb/is_200104/ai_ziff8458/print This article discusses the latest advances in automobile technologies consisting of the increased use in computer technology in vehicles, digital and wireless communication systems, and advanced digital controlled vehicle operating systems.Landmann, Ralf. The Future of the Automotive Industry: Challenges and Concepts for the 21st Century. Warrensdale, PA: Society of Automotive Engineers, 2001. LC Call Number: HD9710.A2 Z8513 2001 LC Catalog Record: 00045810 This publication examines issues currently facing the automotive industry. Fifteen contributions from consultants and other automotive industry professionals discuss factors such as emerging markets, globalization, technological innovation, environmental demands e-business, and approaches for meeting these challenges. Synopsis by Book News, Inc.Sage, Lee A. Winning the Innovation Race: Lessons from the Automotive Industry's Best Companies. New York: Wiley, 2000. LC Call Number: TL240 .S246 2000. LC Catalog Record: 99048040 Table of Contents Publisher Description Contributor biographical information A comprehensive book that describes the process for innovation that takes place in industrial organizations and how successful companies manage to sustain innovation through effective management. Most of these practices are drawn from the automotive supply industry. Review by Books In Print."Concept Vehicles", 21st Century Science & Technology Directoryhttp://www.21stcentury.co.uk/directory/directory.asp?Id=/Recreation/Auto/Enthusiasts/Concepts_Vehicles/ Science & technology portal, which includes a directory on concept vehicle, as well as other automobile technology links.Weiss, Malcolm A., and Heywood, John B. Comparative Assessment of Fuel Cell Cars. Massachusetts Institute of Technology, Laboratory for Energy and the Environment, 2003-001 RP.http://web.mit.edu/mitei/lfee/programs/archive/publications/2003-01-rp.pdf This study examines advances in fuel cell technology and analyzes the use of competitive fuel cell vehicles with present day vehicles driven by internal combustion engines. References1. Fine, Charles H., Lafrance, John C. and Hillebrand, Don. "Meeting the Challenge: U.S. Industry Faces the 21st Century." The U.S. Manufacturing Industry, December 1996. Washington, D.C.: U.S. Dept. of Commerce Office of Technology Policy, p. 44.2. "Robotics and Machine Perception. Cobots: A New Generation of Assembly Tools for the Line Worker."SPIEWeb OE Reports, May 1997. Internet: http://www.spie.org/app/Publications/magazines/oerarchive/may/may97/robotwg.html 3. Automotive Supply Chain: Global Trends and Asian Perspectives. Manila: Asian Development Bank, January 2002, p. 36. 4. Industry and Trade Summary: Motor Vehicles. U.S. ITC Publication 3545, September 2002. Washington, D.C.: U.S. International Trade Commission, p. 37. 1.2. Internet: ftp://ftp.usitc.gov/pub/reports/studies/PUB3545.PDF 5. Farley, Peter. "Hybrids' Rising Sun." Technology Review, April 2004, p. 36. 6. Ibid, p. 36. 7. Weiss, Malcom A., and Heywood, John B. Comparative Assessment of Fuel Cell Cars, February 2003. Cambridge, MA: Massachusetts Institute of Technology Laboratory for Energy and the Environment, p. 1. Internet: http://web.mit.edu/mitei/lfee/programs/archive/publications/2003-01-rp.pdf 8. Jerome, Marty. "Smart Cars." LookSmart, website. Internet: http://www.findarticles.com/p/articles/mi_zdzsb/is_200104/ai_ziff8458 | |||||||||||||
Friday, 24 February 2012
articles
Automated Vehicle Guidance (AVCS) - The Real Aut
Abstract
The potential benefits of automating the guidance of automobiles are extensive especially with regard to better utilization of highway space and safety. Proposals for automobile automation have been made for at least fifty years but a practical system has not been possible because of technology limitations. Now, new advances in technology have brought a practical system within reach. This article discusses the potential benefits of automation, the associated technology requirements, and cost/benefit trades.
Advanced Vehicle Control Systems (AVCS / AVEC)
To many people the subject of self-guided "automatic" automobiles has a "science fiction" flavor typical of projects that are either far beyond the state of the art or impractical from a cost/benefit standpoint. Actually, recent advances in computers, sensors and other related technology have made such a system feasible in the relatively near term and enormous benefits can justify major development and deployment costs.
Advanced Vehicle Control Systems (AVCS or AVEC) is part of the "Smart Highway" initiative (also known as Intelligent Vehicle Highway Systems (IVHS) or Intelligent Transportation Systems (ITS) now receiving considerable study worldwide.
If being able to take a snooze on the way to Schenectady were the only advantage of an automated car guidance system it would be unlikely that the very substantial development and deployment costs for such a system would be justified in the relatively near future. An automated system can have major advantages over the current system in the areas of highway space utilization and safety as described below.
AVCS Space Utilization Advantage
Human drivers are extremely inefficient in their use of highway space. A typical automobile, when parked in a garage, occupies about 100 square feet of space. Adding "overhead" in the form of areas to open the doors and walk around the car brings the total to perhaps 175 square feet. Yet this same automobile, when operated on the highway at 70 miles per hour requires over 5000 square feet of space. Each commuter, from the time he gets on the highway until he gets off requires an average highway space exceeding one-eighth of an acre that "dynamically" moves with him as he travels in order to operate at 70 mph. This is a large amount of space compared to the space most people occupy to live and work. Depending on the length of "rush-hour" and the length of the average commute only a few other people can reuse the space during peak traffic periods. At 70 mph, each car requires an average of about 250 feet of longitudinal space in a highway lane 12 feet wide in addition to a pro rata share of median strips, clover leafs, and breakdown lanes. Few communities can afford the real estate and construction costs associated with providing this much highway space so, as the density of vehicles increases, traffic tends to slow down until eventually bumper-to-bumper conditions are reached.
Traffic engineers consider that one lane of an optimum highway can carry a maximum of about 2000 cars per hour. Capacity varies with speed from about 750 cars per hour at 5 mph (bumper to bumper) to about 1000 cars per hour at 70 mph. The maximum capacity occurs at 25 – 35 mph. The cost and other social impact of increasing highway space in or around American cities is easy to imagine.
Why is such a large amount of space required? One major factor is driver reaction time. If one were to write an equation for determining headway (the space between cars on the highway), reaction time would be a major term. Average reaction time for human drivers is probably on the order of two seconds. An automated system could have dramatically reduced reaction time and headway. Another factor is the precision of human drivers. Notice that while cars are about 6 feet wide, highway lanes are 12 feet wide. An automated system could be more precise and therefore require less lateral space.
Although the dynamics of traffic flow, and the characteristics of tires, engines, and steering equipment do require space to operate, by far the largest requirements for highway space are caused by the characteristics of the human vehicle drivers. An automated system could have much faster reaction time and also other characteristics which would dramatically reduce space requirements. The author has estimated that an initial automated system could have space utilization 2.5 times better than the existing system or that two lanes could carry the same traffic as five lanes carry today. This estimate assumes existing vehicles and highways modified by addition of automation. Eventually about 5 times better utilization could be achieved using vehicles and highways specifically designed for automation.
In addition to the space advantage it is reasonable to believe that automated guidance systems could safely operate at top speeds substantially higher than the 70 mph typical in the U.S. today.
AVCS Safety Advantage
The existing automobile/highway system is extremely mature technology having been under continuous development for 100 years. As such we would expect safety advances to be governed by the limitations of "diminishing return".
If we plot accidents, injuries, or deaths per vehicle mile as a function of time (data are available since 1935) we would expect to see incidence decreasing exponentially and approaching a fixed value as the automobiles and highways approach "perfect" and we approach a condition where all accidents are caused by drivers and not other system faults. The data from Virginia is a reasonable approximation of this model. The consequences of simply extending this curve indefinitely to the right forty involve a staggering toll of deaths and injuries. Automobile accidents are now the leading cause of death in certain segments of the population. Currently, approximately 45,000 people die and 1,000,000 are injured in the US. annually. These rates have historically been approximately constant as improvements in the system are offset by increasing traffic. Future medical advances in the cure of diseases can be expected increase the relative future impact of accidents on public health.
To the extent that we could replace safety related driver functions with technology, an automated system could eventually be very substantially safer than the existing system in that we could bring technology to bear directly on a problem that is now virtually completely driver controlled. Vehicle automation could therefore easily be the greatest public health advance of the twenty-first century.
AVCS Feasibility Considerations
A vehicle guidance system capable of delivering on the promises outlined above would necessarily have to be highly sophisticated and presumably involve substantial electronics, computers, and software. But, vehicle guidance is a very safety critical function. We certainly aren’t going to deploy a new system that we couldn’t prove is safer than the existing system. At the same time, cost is going to be a major factor. Is our technology up to this task?
To explore this issue, lets examine some other transportation systems.
The elevator was first automated in approximately 1940. Because elevators are mechanically guided except for one degree of freedom and other simplifying circumstances, automation could be accomplished without electronics, much less computers. Train automation is somewhat more difficult but also involves mechanical guidance. Mechanically guided automobile systems have actually been proposed but would be much too limited.
Guidance of the Wright brother’s flyer (1917) was by means of cables connecting the pilots hands and feet to the control surfaces. Modern aircraft such as the Boeing 747 are guided in the same manner using cables and pulleys with the addition of mechanical/hydraulic force amplification to allow the pilot to control the much larger control surfaces. However, in the 1980s, aircraft such as the Boeing 767 were introduced where guidance is provided by a digital computer system. In effect the computer and associated software controls the plane and the pilots provide advice and direction to the computer via their controls. The computer systems significantly improve safety by detecting and overriding some types of pilot error. These computer systems (which have substantial redundancy) are considered sufficiently reliable to be used as the only means of guiding an aircraft carrying several hundred people and had enough advantages to justify their development and safety certification cost. Fighter aircraft and the Space Shuttle have similar control systems.
Computer capability per dollar has historically improved extremely rapidly. It is therefore not unreasonable to believe that computer systems and associated components with adequate reliability for vehicle guidance will be achievable for "reasonable" cost in the relatively near term.
Keep in mind that the potential benefits of AVCS are extremely large. The savings in highway construction cost, real estate required for highways, pollution, travel time, and reduced injury and death will justify rather large development and deployment costs. Would you rather have a manual Mercedes or an automated Chevrolet that would get you to work in half the time with half the hassle?
AVCS Architecture Considerations
One possible approach to vehicle guidance automation would be to simply replace the driver with a "robot" system that would perform some of the same functions, only better, using existing highways. Daimler-Benz has conducted studies of a system which uses computer analysis of TV highway imagery for vehicle guidance. However, a "hybrid" system in which some functions are performed by automation equipment in the highway and other functions are performed by equipment in the vehicle has major advantages and is virtually certain to be chosen for any deployed system. It is assumed that the highway and vehicle systems would communicate and cooperate in the execution of the guidance task. Here are some scenarios illustrating potential features of a hybrid system:
Highways automation systems could have "machine readable" signs, marks, or electronic signals to aid in guidance and supplement any imagery analysis system. The author believes that a second, independent, "backup" method of determining relative vehicle position will be necessary in addition to imagery analysis in order to achieve adequate safety.
Highways could centrally control traffic. Since the highway computer network would have access to sensor data from each vehicle as well as its own sensors it would "know" about conditions everywhere on the highway. It could therefore direct traffic to most efficiently use highway space on a regional basis as well as a lane-by-lane basis. For example, visualize two lanes of traffic where one lane is blocked by construction. In the existing system, each pair of drivers approaching the choke point have to essentially negotiate which is going to go first – we all know what that looks like in practice. In a centrally controlled system cars would be directed to interleave well before the choke point. Sight distance would not be an issue. Lateral space could be assigned by the central system based on the size and dynamics of the vehicle as opposed to fixed lanes.
Liability Issues
There is some concern that to the extent responsibility for vehicle guidance is transferred to vehicle or highway systems liability exposure will increase for vehicle manufacturers or highway providers. This situation does not appear to be substantively different from the aircraft guidance systems and air traffic control system case and should not be a show stopper.
Federal Government Role
It is obvious that the successful development and deployment of a hybrid automated vehicle system will require a major commitment on the part of the U.S. federal government to develop and approve the necessary standards for vehicle and highway equipment systems, vehicle and highway certification procedures, vehicle to highway interfaces, etc. As a minimum the government’s role would be similar to its existing role in regulation of aircraft systems, interfaces between aircraft and ground systems, etc.
Economic Considerations
An automated vehicle control system would involve extensive technology in areas where the U.S. has a lead such as computers, networks, software, and aircraft-type systems. If the U.S. took a lead role in developing vehicle automation technology and associated standards, procedures, techniques, and regulations it could be expected to lead the world in vehicle automation in a manner similar to the experience with aviation.
Privacy Issues
A hybrid automated automobile system as described here would involve system "knowledge" of vehicle movement details and therefore could have privacy issues. However, the same issues apply to credit cards, cell phones, and other modern technology and have not apparently inhibited deployment or use of these systems.
Incremental Deployment
It is unlikely that any near term automated vehicle system will be a "hands-off", "take a nap on the way" system. Passenger aircraft still have pilots. Subways still have drivers. Near term guidance systems will aid and support drivers in a manner similar to the existing aircraft systems. Indeed, one of the most interesting and complex questions to be answered is how to design the interfaces between the automation systems and the drivers for best human engineering.
Early automation systems will probably only accomplish part of the guidance solution. For example, one proposed system would control only the longitudinal "headway" distance to the next vehicle, an advanced type of "cruise control". Such a relatively simple system could achieve increased vehicle density and highway capacity while relieving drivers of considerable traffic stress. Another incremental system possibility would measure a candidate parking place, and then, if it was big enough, automatically park the car, eliminating one of the more unpleasant (but relatively simple to automate) driving cho
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