98-186: Roller Coasters Week 4: Basics of Coaster Design Thing of the Week! The Simplest Coaster Ideas ● A roller coaster is all about gaining energy and losing energy ● There are tons of ways to accomplish either goal ● Where does the coaster below have the greatest potential energy? Gaining Energy Lifts ● Lifts propel a train to the top of a hill using one of several methods ● Most of these methods are relatively slow ● Focused on increasing height Lifts - Chain Lifts ● Chain lifts use a chain (shocking) with hooked pieces to convey the train up an incline Lifts - Cable Lifts ● Use a heavy cable with a catch car to rapidly propel the coaster up an incline Lifts - Elevator Lifts ● Train stops on a section of track that then raises up to a higher point; very uncommon Lifts - Spiral Lifts ● Motor on train is powered by a third rail in an upwards spiral Launches ● Typically uses a cable with a catch car that disengages when the train is at top speed ● Exceptions are LIM/LSM launches ● Focuses on increasing speed Flywheel Launches ● Uses a massive wheel to provide the inertia to launch a train ● Used on some Schwarzkopf and Zamperla Motocoasters Weight-Drop Launches ● Dropping a weight to pull the launch cable ● Found exclusively on early Schwarzkopf shuttle loops Hydraulic Launches ● Compresses liquid to high pressures, releases it to a turbine attached to a drum, which winches the launch cable in rapidly ● Used exclusively by Intamin Compressed Air Launches ● Works the same as hydraulic launches, but with air ● Leads to higher rates of acceleration Tire Drive Launches ● Many wheels spin rapidly, pushing the train up to max speed ● One of my home park coasters uses it: The Incredible Hulk Coaster :) ● Intamin’s smaller coasters have begun using these Linear Induction Motors ● Electromagnets on the track switch polarity rapidly ● Magnetic fins on the train are pulled forward then pushed forward, as the polarities switch Linear Synchronous Motors ● A more modern implementation of LIM ● First used by Premier Rides in 1996 ● Disney first had the idea for their PeopleMover transport system in the 1970’s ● Used by many manufacturers nowadays Losing Energy Minor Sources of Energy Loss ● Connections between trains ● Friction of wheels depending on material ● Track material ● Etc. Brakes A. Skid: ceramic plates rub against the bottom of the train; unreliable in rain B B. Clamp/fin: two pieces of metal clamp onto a fin attached to the train C. Magnetic: Metal fin on train passes through magnets that create an eddy current that slows it down; smoother change in speed D. Tire brakes: Tires on the C D side of the track stop cart Roller Coaster Safety Fail Safes ● Brakes require power to open rather than close ● Thus, during a power failure, all brakes are closed ● Anti-rollback devices on chained/cable lifts Restraints ● Coasters usually have some sort of guest restraint ● There are many variations, all designed with a general purpose ● The classic design is the lap bar (shown right) ○ Can be one continuous bar ○ Also individual restraints Restraints - OTSR’s ● Over-the-shoulder restraints ● Still restrain riders’ laps ● Also contain their upper body ● Usually on more intense coasters ● Coaster enthusiasts hate them :( ● Most coasters have trouble accommodating larger patrons Inspections ● What kinds of things should an inspector be looking for? The Block System ● One of the greatest safety inventions of coaster history ● Track is separated into sections called blocks ● Only one train is allowed in a block at a time The Block System - How it Works ● At the end of each block is some sort of brake that won’t allow a train to pass unless the block ahead is empty ● Coasters should be designed such that a train can complete the track even if it stops at a block Accidents ● Most accidents are due to riders being negligent and not listening to instructions ● Others are due to operator error ● Coasters rarely fail due to design, but when they do it usually in a safe way Accidents ● Ninja at Six Flags Magic Mountain ● Daytona Beach Boardwalk (Derailment) (Tree fell in the path of the track) The Design Process The Beginning ● Park executives decide they want a roller coaster ● In chains like Six Flags or Cedar Point, chain executives have more power in where the coaster goes Rough Planning ● Park goes through general ideas, like locations and kind of coaster they want ● They approach manufacturers for bids, or vice versa ○ Smaller parks may not be approached by big companies ● Usually a rough layout is produced by the manufacturer CAD/Safety Considerations ● Manufacturer or their contracted designer begin more detailed calculations of layout ● Terrain, buildings, existing attractions are taken into account ● Safety analysis ○ Restraint analysis ○ Patron containment analysis Wooden Coaster Finalization ● Not a lot of manufacturing ● Usually assembled entirely on-site ● Lumber shipped in; concrete footers poured Wooden Coaster Finalization ● 7-9 layers of flat wood are stacked ● The last 3 layers extend out horizontally so the upstop wheel can go under them ● The wood is laminated together then bolted down ● A piece of flat steel that acts as the main contact point of the track goes on top Wooden Coaster Costs ● Woodies have a lower initial investment ○ A large coaster is usually around $10 million ● Daily inspections are more intensive ● Track sections need to be replaced annually ● A team of carpenters is usually employed to perform these repairs ● Thus, their long-term costs are usually higher Wooden Coaster Costs ● El Toro at Six Flags Great ● Voyage at Holiday World Adventure ($12 million) ($8.5 million) Steel Coaster Finalization ● Track pieces are prefabricated off-site ● Shipped into park ● Concrete footers have been poured usually ● Pieces are bolted together Steel Coaster Finalization ● Straight tubes of steel are bent to pre-specified shapes ● These are welded to the track ties and spine Steel Coaster Costs ● Higher initial investment ○ ~$25 million for a larger coaster ○ Lots more engineering and design ● Typically have more friction than wooden coasters due to polyurethane wheels ○ Shorter and slower than similarly sized steel coasters Steel Coaster Costs ● Kingda Ka at Six Flags Great ● Intimidator 305 at King’s Dominion Adventure ($25 million) ($25 million) Operating Considerations Capacity ● A coaster’s throughput of riders, usually in riders per hour ● “Good” capacity is around 1400-1800 riders per hour ● “Bad” is around 800 riders per hour ● In the industry, the rough number is Theoretical Hourly Ride Capacity, or THRC Capacity Factors ● Obviously duration of the ride ● With roller coasters, usually number of train cars and number of trains operating simultaneously ● Down time is usually not factored in Next Week Design Challenge 1!.