Last Updated on 06.08.2024 by hrushetskyy
How is a new tire developed?
A brief description is given in this article about how new fabric polyester was commercialized in tires. The introduction to a new fabric into tires is a venture of major proportion. The origin of this venture began with an analysis that led to a selection sequence. An exhaustive study was made to determine the most pressing tire performance needs. A theoretical investigation then pinpointed the required fabric parameters necessary to meet these tire needs. In the meantime an initial evaluation of nine new fabrics (acrylic fiberglass MXDA Nomex polycarbonate polyester polyolefin poly-urea vinai) was undertaken. Then a programmed study was set up including regression analysis of existing data to optimize current properties and determine a “fit” to the required parameters.
Once polyester was chosen the program entered the second stage development and commercialization. A venture analysis program was undertaken to define the required technology to be developed. After exhaustive studies the overriding need was determined to be one of achieving cord-to-rubber adhesion. Next extensive tire testing was organized. As part of the venture analysis program the technical and commercial feasibility of introducing polyester into tires had to be determined. The entire process was studied from polyester raw materials to the finished tire. Economics of producing polyester fabric (versus other fabrics) were studied. Long-range raw material costs were projected. Variations and changes from existing fabric and tire processes were investigated. The degree of technical sophistication required to arrive at a workable process was examined. The nature of the desired market (such as premium tires or original equipment tires) became a factor. Even the reaction of competition had to be considered. Management decision tools were used to maximize feedback and to take into consideration the effects of specific actions.
Polyester lends itself ideally to current tire-producing facilities.
The only new hardware installations needed were those required tor the polyester adhesive system. A program of volume evaluation was an integral part of planned commercialization.
The mileage accumulated in testing tires was more than two million miles on the proving grounds; more than 16 million miles on fleets; and more than one million miles on laboratory wheels.
In the commercialization of polyester the problems of investigating evaluating coordinating and controlling were solved by the use of a decision network. The hexagons represent decision points. The letters represent negative decisions.
TIRE TECHNOLOGICAL FORECASTING
What lies ahead for tires in 1975? 1980? 2000? This article applies technological forecasting to tire R&D.
Technology proceeds as an evolutionary advance in small steps.
Decisions tend to be made in the general direction of existing progress trends. In recent years the belief has arisen that it is no longer sufficient to look “toward” the future. Instead it is essential to look “at” the future. This discipline is called technological forecasting. Technological forecasting permits one to “go” td the future and examine it.
As a scientific discipline technological forecasting dates from about 1960. The discipline has been used widely by the military and “think tanks” to analyze the course of technology into the future. The analyses are made with probabilistic estimates of the rate direction and extent to which a technology will develop in a given time frame.
Technological forecasting is a technique for identifying alternate futures assessing the likelihood of each and directing R&D activities toward products or technology that will be needed. As a result technological forecasting can be used to analyze and shape the future.
Three types of technological forecasting are generally recognized: exploratory normative and intuitive.
Exploratory forecasting starts with current technology and then makes mathematical extrapolations based on historical patterns, normative forecasting starts with future needs or goals then works backward to identify the technology required to fill these needs. Intuitive forecasting is a speculative projection into the future and is not generally based on quantitative inputs. Science fiction falls into this category. The longer the time span being examined the more important intuitive forecasting becomes.
The methodology of technological forecasting has not been formalized although many techniques have been well structured.
Exploratory Forecasting
Exploratory forecasting projects future feasibilities from the present state of the art. Extrapolations can be made for any technological parameter for which a data base exists. The more important techniques for exploratory forecasting are trend extrapolation envelope curves and trend correlation.
Trend Extrapolation: Trend extrapolation is a simple forward projection from past performance. It is a plot of achievement versus time. Trend extrapolation assumes that those forces that created the prior pattern of progress will be more likely to continue than to change and those forces are more likely to extend the previous pattern of progress than to produce a different pattern.
The tire industry has many examples of this type. One example is the billions of miles of passenger travel. Travel has increased steadily since World War II. This plot indicates that passenger travel will approach 1200 billion miles by 1980.
Envelope Curves: Envelope curves are used to project the effect of more than one technology on a parameter.
The conclusion is axiomatic that an S-curve is followed by a technology breakthrough. Thus an S-curve is a warning signal in forecasting. Tire tread-wear is a textbook example.
An envelope extrapolation indicates that a 100000-mile tire might be possible before the year 2000. This envelope curve illustrates the importance of plotting macro-variables. Macro-variables (in this case bias tires and belted tires) tend to extrapolate more smoothly. The micro-variables affecting tread-wear might include such items as changes in elastomers carbon blacks fabrics tread patterns and tread flatness. Plotting macro-variables is more erratic since considerable interaction occurs. A properly designed computer program can break out the macro-variables where desired.
Fore casters generally “think logarithmically” since technological progress proceeds exponentially.
Particular attention must be paid to constraints. Actually tire tread-wear improved 50 percent over this time range when compared to similar vehicle and service conditions.
What happened during this period was an increase in the severity of driving conditions (greater horsepower adoption of power steering and power brakes completion of many expressways and turnpikes and a significant increase in average speed).
The width of the white sidewall on a tire has been constantly diminishing. The constraint of course is a zero-width sidewall (or black tire).
Technological forecasting clearly predicted that this ultimate limit would be reached and there would be need for an innovation (assuming that a black tire is esthetically undesirable). One innovation was the introduction of a tire with the name of the manufacturer in white letters.
Trend Correlation: Trend correlation is another technique of exploratory forecasting. As its name indicates it is based on relationships between multiple trends. One trend for example may be a precursor and lead another. The top curve shows the aspect ratio (cross section height to cross-section width) of race tires from 1964 to 1970. As indicated race tire aspect ratios have been continually decreasing.
Passenger tires generally have a much higher aspect ratio. This curve also shows passenger tire aspect ratios decreasing but at a much lower rate. However about 1966 the passenger tire curve split with one segment paralleling the race tire curve yet with a six-year lag. A forecast from these curves indicates that some passenger tires could have an aspect ratio as low as 0.4 by 1975.
Normative Forecasting
Normative forecasting starts with needs that are projected to exist at some future time and then works backward to develop the technology to fill these needs. This type of forecasting is less concerned with actual future needs that are determined by intuitive forecasting. It is more concerned with defining the science and technology that will be required to meet these needs and identifying available options. The more important techniques of normative forecasting are morphological analysis relevance trees and input-output models.
Morphological Analysis: Morphological analysis provides a method for systematically exploring all opportunities at the technological level. With this method a technology is broken down to its basic parameters identified indexed and classified. These parameters then are recombined in as many ways as possible to achieve new goals and novel capabilities.
Tire people talk in the narrow view of radial and bias/belted tires. In the “total thinking” of morphological analysis however these are only special cases in an overall spectrum of belt and carcass angles.
The top sweep represents the radial tire; the bottom sweep represents the bias/belted tire. The areas of highest probability of success for future R&D are the enclosed blank space and the external areas immediately adjacent to the existing sweeps.
The probability of technological success is a decreasing function of the morphological distance from current technology. Point Y for example represents a cast tire; Point Z represents a 100 percent fabric tire. A more complex morphological space would include (in addition to the above) such items as cord path composite configuration aspect ratio rim diameter and rim width.
Combined with morphological analysis is a figure of merit for the tire desired. Depending on the need a different balance of tire requirements will be specified. Computer utilization is required for thorough application of morphological analysis.
Figure of Merit
| Tire Requirement | Tire A’ | Tire B+ |
| (%) | (%) | |
| Traction | 35 | 25 |
| Tread-wear | 15 | 10 |
| Ride | 10 | 10 |
| Rolling resistance | 10 | 25 |
| Handling | 10 | 10 |
| Road hazard performance | 10 | 10 |
| Noise | 10 | 10 |
| Total | 100 | 100 |
This list can be expanded as required. +The number of tires can be expanded as required. A tire can be specified for each need.
Relevance Tree: The relevance tree is closely related to morphological analysis since it is an approach to total thinking. A relevance tree is a hierarchy of relationships affecting a technological goal. A fully developed tree displays various technical disciplines and sub-disciplines in a well-structured pattern. Alternative paths can be spotted and new avenues of approach uncovered. An important factor in tires is resistance to tread-wear. Similar trees can be constructed for any technological goal. Relevance tree techniques also require the use of computers.
Input-Output Models: From the previous techniques elaborate input-output models of normative forecasting can be constructed. Most of the published information on modeling has come from the military corporate modeling or dynamic programming involves proprietary information.
Intuitive Forecasting
Intuitive forecasting is a method for anticipating the future and its needs. Interest in intuitive forecasting was generated by science fiction flash of genius and brainstorming. Being “unstructured” these methods are limited. The two sophisticated methods in use today are scenario and Delphi probe.
Scenario: In scenario intuitive forecasting arbitrary future environments are anticipated and the effect on technology is projected. In the tire industry for example a scenario might be constructed that assumes wide use of mass transportation. Various types of mass transportation can be envisioned: buses (reserved lanes dial-a-ride); trains (high-speed train’s rubber tire trains); personal rapid transit (surface guide ways monorails); tubes (subways high-speed tube vehicles); and continuous capacity (beltways network cabs). The forecast then treats each system and its effect on tire technology. Actually rubber tires appear to be quite adaptable to mass transit systems.
Another scenario might assume a continuing desirability for use of personal vehicles. The automobile provides door to door transportation on instant demand. In addition studies have shown that the automobile fills a need for escape a sense of freedom in a mass society. In this scenario many alternatives can be envisioned: coast-to-coast freeways at 200 mph with electronic guidance systems multi-model cross-country trains carrying personal vehicles for end use (pallet system) and cross country freeways for air-cushion vehicles that can be converted to urban use. Each situation will project a different tire technology. Conceivably a basketball tire could be used in conjunction with an air-cushion vehicle for greater utility.
A unified transportation system scenario might be envisioned as follows: center city travel (mini-autos continuous capacity); suburban travel (autos buses trains personal rapid transit tubes); statewide travel (autos on freeways); nationwide travel (autos on interstates aircraft); and international travel (aircraft). The effect of this unified system on tire technology then can be projected.
Delphi Probe: The Delphi probe is often called a consensus of experts since it is a systematic solicitation of expert opinion. The Delphi probe was developed by Helmer Dalkey and Gordon of the Rand Corporation. The Delphi probe is a technique to utilize the collective wisdom of experts by anonymity (eliminate interpersonal influences) iteration (provide feedback of reasoning) and convergence (develop utmost wisdom). Thus the Delphi method is a carefully designed program of sequential individual interrogations refined through feedback.
In a Delphi probe a group of experts is requested by mail to list the most important developments they anticipate in a given time frame (for example now and the year 2000). A compilation then is sent to the same experts asking them to supply a date when the forecasted events have a better than 50/50 probability of realization. The dates are refined by further questionnaires (iterations). The responses must be anonymous and without collaboration.
Summary
A comprehensive technological forecast generally adopts the following sequence of techniques. Primary prerequisite is a data base. Extrapolation is used first to project a surprise-free trend. Intuitive forecasting then anticipates the future and its needs.
Normative forecasting defines the technology to meet these needs. An iterative process between exploratory and normative forecasting enhances their utility. Finally the technological forecasts are used in planning R&D and resource allocation.
Thus technological forecasting defines the policy options available to a company and provides a basis for selecting among alternative technology programs.
CONCLUSION
Tires are the means to support propel and guide vehicles. The first tires were made of cotton and natural rubber. They frequently lasted less than 1000 miles. It was common to carry six spares. Today’s modern tires often deliver more than 40000 miles.
Chronology of Tire Technology
| Year | Innovation | Year | Innovation |
| 1839 | Rubber vulcanization | 1939 | RFL adhesives |
| 1845 | Air tube device patent | 1942 | First synthetic tire cord |
| 1888 | First tire | (nylon in military tires) | |
| 1896 | First tire on automobile | 1943 | Styrene/butadiene synthetic rubber tire |
| 1903 | First tire on airplane | ||
| 1904 | Flat tread | 1947 | Nylon tire cord (commercial tires) |
| 1905 | Nonskid tread pattern | ||
| 1906 | Rubber accelerators | 1948 | Radial tire |
| 1912 | Carbon black | 1949 | Bladder cure (B-O-M) |
| 1924 | Rubber antioxidants | 1950 | Tubeless tire |
| 1925 | Cord ply fabric replaces | 1954 | Synthetic natural rubber |
| square-woven | 1962 | Polyester tire cord | |
| 1929 | White sidewalls | 1967 | Fiberglass tire cord |
| 1931 | First synthetic rubber | 1967 | Bias/belted tire |
| (Neoprene) | 1968 | Foam-filled tire | |
| 1935 | Modern tire dimensions | 1968 | Federal tire standards |
| 1937 | Wire tire cord | 1970 | 600-mph land speed record |
| 1938 | Rayon tire cord | 1971 | Moon tire |
Tire technology is a complex combination of art science and engineering that brings together a variety of disciplines. Tire development involves knowledge in the areas of tire geometry dynamic tire behavior the chemistry and technology of component materials and composite structures.
Extensive tire testing in the laboratory and on the proving grounds is utilized to evaluate end-use performance parameters. Finally tires to meet a variety of service conditions must be manufactured in quantity. The result is a product that has made possible today’s sophisticated system of transportation.
