Either as an introductory text or a practical professional overview, this book is an ideal reference. Multibody Systems Approach to Vehicle Dynamics aims to bridge a gap between the subject of classical vehicle dynamics and the general-purpose computer-based discipline known as multibody systems analysis MBS. The book begins by describing the emergence of MBS and providing an overview of its role in vehicle design and development.
This is followed by separate chapters on the modeling, analysis, and post-processing capabilities of a typical simulation software; the modeling and analysis of the suspension system; tire force and moment generating characteristics and subsequent modeling of these in an MBS simulation; and the modeling and assembly of the rest of the vehicle, including the anti-roll bars and steering systems.
The final two chapters deal with the simulation output and interpretation of results, and a review of the use of active systems to modify the dynamics in modern passenger cars.
This book intended for a wide audience including not only undergraduate, postgraduate and research students working in this area, but also practicing engineers in industry who require a reference text dealing with the major relevant areas within the discipline.
Maurice Olley, one of the great automotive design, research and development engineers of the 20th century, had a career that spanned two continents. Olley is perhaps best known for his systematic approach to ride and handling. His work was so comprehensive that many of the underlying concepts, test procedures, analysis, and evaluation techniques are still used in the auto industry today. Thus they remain as useful today as when they were first developed.
For example, they are easily programmed for study or routine use and for checking the results of more complex programs. This new book provides insight into the development of chassis technology and its practical application by a master. Racecar data acquisition used to be limited to well-funded teams in high-profile championships.
Today the cost of electronics has decreased dramatically making them available to everyone. But the cost of any data acquisition system is a waste of money if the recorded data is not interpreted correctly.
This book updated from the best-selling edition contains techniques for analyzing data recorded by any vehicle's data acquisition system. It details how to measure the performance of the vehicle and driver what can be learned from it and how this information can be used to advantage next time the vehicle hits the track.
Such information is invaluable to racing engineers and managers race teams and racing data analysts in all motorsports. Whether measuring the performance of a Formula One racecar or that of a road-legal street car on the local drag strip the dynamics of vehicles and their drivers remain the same.
Identical analysis techniques apply. Some race series have restricted data logging to decrease the teama's running budgets. In these cases it is extremely important that a maximum of information is extracted and interpreted from the hardware at hand. A team that uses data more efficiently will have an edge over the competition.
However the ever-decreasing cost of electronics makes advanced sensors and logging capabilities more accessible for everybody. Very highly recommended.
File Name: racing car vehicle dynamics by william milliken pdf. MRA engages in analytical and testing contracts over the range of vehicle dynamics topics. Experimental Evhicle Association. Research Article Vehicle Unsteady Dynamics developed and further refined based on considering the top Figure 7: 1-stage thermostat. Milliken Milliken, Jr. Guided Reading Leveling Chart. Fiat Vs! Read more. Tutorials by hugo viva la vida.
Simplified Transient Stability and Control This handbookfor airplanes with serial nos. Libraries near you: WorldCat. Edition Notes Includes bibliographical references p. Classifications Dewey Decimal Class M55 The Physical Object Pagination xxviii, p. Community Reviews 0 Feedback? Lists containing this Book Rcvd from Rejectedpiece. Race Car Vehicle Dynamics Workbook.
Author : L. Racing Chassis and Suspension Design. Tune to Win. Automobile racing. Author : Thomas C. Author : Jeffrey P. For cola one of these is literally water, supplied in the United Kingdom by the local Water Authori- ties. Other basic ingredients are the "essence" in plain language, the taste used in tiny amounts and supplied as a concentrate by the parent cola company,5 beets for sugar, corn for caramels to provide the "cola" color and additional taste , fir trees for cardboard to make the carton, and bauxite or recycled cans to create aluminum for the can.
As shown in the value stream map in Figure 2. Although the ore could in principle be mined in small amounts and sent along to the next step within a few minutes of the receipt of an order, the mining machinery is truly massive and the actual process involves scooping out millions of tons of bauxite at a go in accord with a long-term production forecast. T h e mountain of ore is then transferred to massive trucks for shipment to a nearby chemical reduction mill where the bauxite is reduced to powdery alumina.
When enough alumina is accumulated to fill an ultralarge ore carrier over two weeks or so; about , tons or enough for 10 million cans , it is shipped by sea—a four-week trip—to Norway or Sweden, countries with cheap hydroelectric power, for smelting. After about a two-month wait at the smelter, the application of an enor- mous amount of energy twenty times that needed to melt down and recycle old cans reduces two tons of alumina to one ton of aluminum in about two hours.
Again, scale in smelting dictates that large amounts of aluminum be created in each batch, with the molten aluminum poured into dozens of ingots one meter on each side and ten meters long.
After about two weeks of storage at the hot rolling mill, the ingot is heated to five hundred degrees centigrade and run through a set of heavy rollers three times to reduce the thickness from one meter to three millime- ters.
The actual rolling process takes about one minute, but the machinery is extremely complex and difficult to change from one specification of prod- uct to another, so management has found it best to wait until there are orders in hand for a large amount of material of a given specification and then to process these orders all at once. When this is done for the specifica- tion of aluminum needed for cola cans, the aluminum sheet emerging from the rolling mill is wound onto a ten-ton coil and taken to a storage area, where it sits for about four weeks.
When needed for the next step, the coil is taken from storage and shipped by truck to a cold rolling mill, either in Germany or Sweden, where it is stored for about another two weeks.
Cold rolling at feet of aluminum sheet per minute—about 25 miles an hour squeezes the aluminum sheet from 3 millimeters to. Because the cold rolling equipment is also extremely expensive and difficult to change over to the next product, the managers of the cold rolling mills have also found it most economical to accumulate orders for products of a given specification and do them all at once.
The thin sheet emerging from the cold roller is then slit into narrower widths, wound onto ten-ton coils, and stored for about a month on average.
When needed for can making, the aluminum coils are shipped by truck, by sea, and again by truck to the can maker in England, where the coils are unloaded and stored, again for about two weeks. When needed, the coils are taken from storage to the can making machinery and run through a blanking machine which punches circular discs out of the aluminum sheet at the rate of four thousand per minute. The discs are then fed automatically into "wall drawing" machines, which punch the disc three times in succession to create a can without a top, at the rate of three hundred cans per minute per machine.
Thirteen forming machines are downstream from each blanking machine. From the forming machines, the cans travel by conveyor through a washer, a dryer, and a paint booth applying a base coat and then a top coat consisting of the cola color scheme plus consumer information in different languages and varying promotional messages.
The cans then travel through lacquering, necking and flanging to prepare the cans to receive their tops after filling , bottom and inside spraying to prevent discoloration and any aluminum taste from getting into the cola , and on to final inspection.
However, it is also extremely expensive to change over from one type of can to the next and one paint scheme to the next, so management tries to produce large lots of each type.
From the can maker's standpoint this is clearly the most economical approach, and it also meshes with the practice of the smelter, hot roller, and cold roller of processing specific types of aluminum in large batches. After inspection, the cans proceed to an automated palletizing machine which loads the empty cans on pallets, eight thousand to each pallet, and sends them to a massive warehouse for storage until needed, usually four weeks.
In the warehouse, they are stored by type of can because the bottling firm eventually filling the cola cans needs a variety of cans with different labels for beverages besides plain cola for example, diet cola, caffeine-free cola, cherry cola.
And even for plain cola, the bottler must support many different packaging configurations and promotional campaigns. Each pack- age and many marketing campaigns require different information to be painted on the cans. They are then depalletized and loaded into massive can filling machines, where they are washed and filled. It is at this point that the major tributary streams converge in a massive tank adjacent to the filling machine.
In this step, water, caramels, sugar, and essence are carefully mixed, and carbon dioxide the fizz is added to create cola. Figure 2. The value streams for these items also require detailed analysis by Tesco, the bottler, and their suppliers, but the method for value stream analysis is best illustrated by sticking to the longest stream. After the cola is poured into the cans at the rate of fifteen hundred cans per minute , the cans are sealed with an aluminum can end containing the familiar "pop top," supplied through a separate but very similar process by the can maker.
The cans are then date stamped and packed into cartons of varying numbers of cans, eight in the present case. Each type of carton has its own paint scheme and promotional information.
The mixing and filling process, which brings all of the tributary value streams together, requires only one minute to proceed from washing to packing, but it is expensive and time-consuming to change over. In addition, putting cola in a few cans and then a clear soda in the next can requires purging the whole fill system, so the bottler has found it most economical to run large lots of each type of beverage through its complex equipment.
A process called "stocking. Once at the Tesco warehouse things move much faster. Incoming pallets are stored for about three days before cases are taken from the pallets and placed in roll cages going overnight to each store. Once at the retail store, the roll cages are taken from the receiving dock to a storage area in the rear or direcdy to the shelves, and the cola is sold in about two days.
When the cola is taken home it is typically stored again, at least for a few days, perhaps in the basement if the shopper has bought a number of cartons to take advantage of a special promotional offer.
Then it's chilled and, finally, consumed. The last stepprobably requires about five minutes, after nearly a sear along the stream. A final important step, also shown in Figure 2. Currendy, only 16 percent of aluminum cans in the U. If the percentage of cans recycled moved toward percent, interesting possibilities would emerge for the whole value stream.
These activities would suddenly convert from type 1 in our typology—muda but unavoidable—to type 2—muda that can be completely eliminated right away. The slow acceptance of recycling is surely due in part to the failure to analyze costs in the whole system rather than just for the recycling step in isolation.
When laid out this way, action by action, so it's possible to see every step for a specific product, the value stream for physical production is highly thought- provoking. First, as shown in Table 2. More than 99 percent of the time the value stream is not flowing at all: the muda of waiting. Second, the can and the aluminum going into it are picked up and put down thirty times.
From the customer's standpoint none of this adds any value: the muda of transport. Similarly, the aluminum and cans are moved through fourteen storage lots and warehouses, many of them vast, and the cans are palletized and unpalletized four times: the muda of inventories and excess processing.
Finally, fully 24 percent of the energy-intensive, expensive aluminum coming out of the smelter never makes it to the customer: the muda of defects causing scrap. TABLE 2. DC 0 0 3 days — 8 24 Tesco store 0. The jump in scrap at the can maker is due to the loss of about 14 percent of the material in the punch.
The loss at the bottler is mainly from damaged cans rejected as they are loaded in the filling machinery. Because the cans are stored empty with no internal pressure, they are easy to damage in handling. The jump in scrap rate at the home of the customer, shown in brackets, is the consequence of recycling only 16 percent of the 76 percent of the original aluminum which reaches the customer.
The boats, warehouses, and processing machines we have been describing are truly massive and we can see that the primary objective of technologists in the beverage industry has been to scale up and speed up this equipment while removing direct labor, in a classic application of the ideas of mass production.
Indeed, this machine may be much more expensive than a smaller, simpler, slower one able to make just what the next firm down the stream needs Tesco in this case and to produce it immedi- ately upon receipt of the order rather than shipping from a large inventory.
For the moment, let's just reemphasize the critical leap in embracing value stream thinking: Stop looking at aggregated activities and isolated machines —the smelter, the rolling mill, the warehouse, and the can filling machine.
Start looking at all the specific actions required to produce specific products to see how they interact with each other. Then start to challenge those actions which singly and in combination don't actually create or optimize value for the customer.
Ordering Cola If it takes days to bring a cola from bauxite to Tesco and a similar amount of time to make most of the other items along Tesco's aisles , there is a clear problem in ordering. Either orders must be completely uniform over time so the producers all along the stream can operate stable schedules with litde inventory, or the upstream producers must maintain large inven- tories at every stage to deal with shifts in demand, or Tesco's customers must learn to live with shortages.
None of these is desirable because all create muda. It has dramatically reduced "stock-outs" a situation of not having a product the customer wants while also slashing its own in-store and warehouse inventories by more than half. Because Tesco was already one of the most efficient grocers in the world when it started this process, it appears that its current inventories are only half the U. However, Tesco has recently realized that to move even further in reduc- ing inventories, stock-outs, and costs on a total system basis where more than 85 percent of the costs of a typical product like cola are outside Tesco's corporate control , it -will need to improve responsiveness and ordering accuracy all the way up its value stream, running across seven firms in this particular case.
Tesco installed a Point-of-Sale POS bar-code scanningjsvstem in the checkout lanes of all of its stores in the mids. This permitted each store to maintain a "perpetual inventory" of exactly how much of every item it had on hand and to make more accurate orders to suppliers.
This was possible because every time a customer in the aisle took a carton of cola past the checkout, the system noted this fact along with the recent rate of sales and the number of cartons remaining. Replenishment orders could be auto- matically generated. A few years later, Tesco transferred decision making on what each store would purchase and when from the store manager, who had been ordering direct from each supplier, to a centralized system where Tesco placed orders combined from all stores to suppliers.
At the same time, it opened a dozen Regional Distribution Centers RDCs in England so that suppliers for more than 95 percent of all sales volume the exceptions being milk, sugar, and bread would ship to the RDC rather than the store.
Instead of sending a small truck, partially loaded, to each store, each supplier could send a large truck to each RDC and Tesco could send another large truck to the retail store each night.
In , Tesco took a revolutionary step for the grocery industry by moving toward daily orders rather than weekly or even monthly for all fresh products and for many long-shelf-life items. Today, when each store takes inventory at the end of each day, the Tesco ordering system calculates the quantity needed to restore normal stocks plus any special demand likely to be caused by the day of the week, the time of year, the weather, or a sales promotion. After a quick review by the store manger, to check for glitches in the assumptions, this information is dispatched to Tesco's central computer.
There, the requirements from all stores in each region are accumulated and orders are dispatched electronically to each supplier during the night. Thus, orders made by each Tesco store on Monday night result in replenishment goods from suppliers reaching each store before it opens on Wednesday morning,14 effectively creating a twenty-four-hour continuous replenishment system. The system is shown in Figure 2. At the same time, the stocks on hand of the average good in the retail stores plus the RDCs fell from 21 to For "fast movers" like cola, accounting for more than half of Tesco's total sales, inventories at the RDC and the retail store combined are now only 3 to 5 days.
However, as Tesco did this, they learned the limits of what can be accom- plished by one firm alone. Their production methods—with high-speed machines, long changeover times, and large batches—have given them no real choice.
Because the bottler cannot get rapid response from its upstream suppliers to changing levels of demand, it con- tinues to order batches of goods at weekly, monthly, or even quarterly intervals in the case of some raw materials. If Tesco wants to shrink costs and improve the reliability of the 85 percent of the value stream it does not directly control, it's obvious that the upstream firms must collectively rethink their operating methods, and this is how lesco and the Lean Enterprise Research Centre joined forces.
While it is still in the early stages, the process of jointly conducting the analysis just described should gradually change Tesco, the bottler, the can maker, the cold roller, the hot roller, the smelter, and the bauxite miner from seven isolated adversaries into a team of collaborators, indeed into a lean enterprise.
Creating Cola The final element in the cola story is the value stream for product develop- ment. Historically, in the grocery business, first-tier suppliers like the bottler or the branded purveyor of goods have been responsible for the great bulk of product innovations and introductions. Yet only a brief effort to list the activities in the value stream culminating in the launch of a new product raises many questions.
Typically, a firm like the bottler is continually looking for new products to defend its current market share, to expand its scope of offerings and justify more shelf space at Tesco , and to substitute products with higher margins for old standbys like cola. In the industry, the typical product development cycle is about one year and consists of a number of product clinics followed by larger product trials culminating in the decision for a full-scale launch.
Although the actual steps involved are very simple and typically involve very little true "research and development," they are conducted sequentially so that if one looks down on a product concept from a bird's-eye view it is quickly apparent that during most of the development period the concept is sitting still, awaiting feedback from the group which conducts the clinics on all of the firm's products or awaiting its place on the schedule of the depart- ment which conducts small-scale market trials for all products.
Simply reducing development time and expense, while highly desirable, will not be enough to have much effect on this value stream, so Tesco has started to rethink the product development process on a more fundamental level in terms of value.
Perhaps, just as the individual steps in the value stream are incomprehensible in isolation, customers do not really want to shop for isolated items. Would it perhaps be better for Tesco and its bottler to joindy undertake the development of the full complement of beverages necessary to keep Tesco customers happy, and for Tesco to develop longer- term relations with its customers so they would not be strangers?
Toward this end Tesco has just launched a frequent-shopper program that will gather purchase pattern data on every regular customer and should permit a more coherent value stream in product development. Putting Value Stream Analysis to W o r k Having looked at the specific steps involved in the value stream for oiie specific product, we are ready to put our findings to work more broadly. Instead, we see a large num- ber of steps in the second category.
They clearly add no value—they're muda—and they therefore become targets for elimination by application of lean techniques. Note that in performing this analysis we are not "benchmarking" by comparing Tesco's cola value stream with those of its competitors. They tend to get distracted by easy-to-measure or impossible-to- emulate differences in factor costs, scale, or "culture," when the really im- portant differences lie in the harder-to-see ways value-creating activities are organized.
Our earnest advice to lean firms today is simple: To hell with your com- petitors; compete against perfection by identifying all activities that are muda and eliminating them. This is an absolute rather than a relative standard which can provide the essential North Star for any organization. In its most spectacular application, it has kept the Toyota organization in the lead for forty years. However, to put this admonition to work you must master the key techniques for eliminating muda.
It all begins with flow. Usually, you make an appoint- ment some days ahead, then arrive at the appointed time and sit in a waiting room. When the doctor sees you—usually behind schedule—she or he makes a judgment about what your problem is likely to be. You are then routed to the appropriate specialist, quite possibly on another day, certainly after sitting in another waiting room.
Your specialist will need to order tests using large, dedicated laboratory equipment, requiring another wait and then another visit to review the results. Then, if the nature of the problem is clear, it's time for the appropriate treatment, perhaps involving a trip to the pharmacy and another line , perhaps a trip back to the specialist for a complex procedure complete with wait.
If you are unlucky and require hospital treatment, you enter a whole new world of specialized functions, disconnected processes, and waiting. If you take a moment to reflect on your experience, you discover that the amount of time actually spent on your treatment was a tiny fraction of the time you spent going through the "process. You put up with this because you've been told that all this stopping and starting and being handed off to strangers is the price of "efficiency" in receiving the highest-quality care.
We've already looked briefly at another service, a trip involving an airline. And most of the time the experience is even worse than the Joneses' family trip to Crete because rather than taking a direct flight you must go through a hub for sortation. In the end, the time you spend actually moving along the most direct route is likely to be litde more than half the total time required to get from door to door.
Yet most travelers put up with this system without dreaming of anything better. Health care and travel are usually called "personal services," in contrast with "products" like VCRs, washing machines, Wiremold's wire guides, and Tesco's beverages. Actually, the major difference is that in the case of health care and travel, you the customer are being acted upon—you are necessarily part of the production process.
With goods, by contrast, you wait at the end of the process, seemingly beyond harm's reach. However, there is no escap- ing the consequences of the way the job gets done even if you are not directly involved. Let's take just one example for a common good, the single-family home. Henry Ford dreamed about mass-producing homes using standard but mod- ularized designs with the modules built in factories to slash design and production costs while still providing variety.
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