G3 RoboCoaster

The golden age of amusement parks

The evolution of safety systems and more efficient networking has worked wonders for what's possible in theme parks.

What's the greatest thrill you can give hordes of expectant ticket-holders without compromising their safety? That has been the question at the heart of theme-park design for over 100 years.

Around a decade ago, press rooms were flooded with calls from theme-park visitors claiming to have experienced traumatic brain injury after riding high-g-force theme-park rides. Although the claims were deemed unfounded by scientists and biomedical engineers, they have put the spotlight on to the possibilities, and responsibilities, of theme-park design.

Today, ride designers are exploring new options to achieve the next big thrill, and the technology behind these thrills has become as widely discussed as the experience itself.

Networking of automated theme park rides has been common since the 1970s, mostly in the form of point-to-point cabling, though recent years have also seen the integration of Ethernet technology. In most cases, more than one car is on the track at a time so a blocking system is used to stop collisions.

Historically, blocking systems would be controlled by two or more individual programmable logic controllers (PLCs) in different sequences, but modern rollercoasters often use just one. If at any time one car comes within a certain range of another, the PLC will trigger an anti-collision system to avoid an accident. The monitoring of each ride can take place centrally or remotely, allowing operators to check the health and status of every machine in the park.

The operation of amusement-ride machinery has many similarities to the operation of large industrial machines, according to Mark Stilwell, electrical engineering manager at Thorpe Park, owned by Merlin, one of the largest theme park operators in Europe. Variable speed drives, PLCs and other hardware such as restraint locking mechanisms are all interconnected and communicate on one network, enabling rapid movement of data.

"Industrial automation overlaps considerably with our industry," says Stilwell. "Both industries are very concerned with machine safety and we approach it in similar ways, so many of our standards and directives are the same. Networking our systems allows us to interrogate remote devices for their status and access their stored data."

But despite the similarities, the design and production of park robotics is markedly different to that of their equivalents in the industrial sector. From a manufacturing point of view, industrial robots are rated by payload and extremity of reach, but for passenger-carrying robotics the safety control measures dominate the task of the machine, and eventually the cost.

"You define a task for an industrial robot and the cost is dictated by payload, reach and the weight with a safety working factor of, say, two," says Gino De Gol, president of Robocoaster, a UK-based core ride system manufacturer. "With a passenger-carrying robot, all design factors are dictated by the payload, in this case a human being, and so it requires a much higher safety working factor, usually around a factor of four."

With these high safety levels in mind, a new theme-park ride is commissioned through a two-step process before the proposed design can even go to review and initial testing. Park directors write the specification before consulting the engineering department for advice on control systems. Structural design is completed in CAD software and a manufacturing partner is then selected to build the ride. A team of civil engineers piece together the steel structures before each section is sent to the park for installation.

Better safe than sorry

To ensure robust safety levels, independent audits are carried out throughout the year, as well as daily tests by onsite engineers. The control systems are checked by testing the tolerance of the lateral bars, the functionality of the blocking systems and the parameters of the magnetic braking systems.

During the winter UK parks close to the public, but this is not an opportunity for theme-park operators to relax. This is the season for rides to be stripped down and inspected part by part. Non-destructive testing is paramount to the safety of all the equipment in the park and HSE legislation dictates that each theme park must perform this annual in-depth procedure.

Disassembled to its bare-minimum components, each ride is put through a rigorous inspection of magnetic testing and X-rays to detect cracking, pitting and fretting that may affect performance and safety. Operational and maintenance legislation determines the lifecycle of some components, but if metal fatigue is detected in a part then it will automatically fail and have to be replaced.

Rides are typically very large devices and a clear view of the entire machine from one position is usually not possible, meaning an accident could easily happen out of clear sight. As safety technology has developed in rides, standardisation efforts have stepped up to manage it. Steve King, industry expert and independent consultant for ASTM (American Society for Testing and Materials), says standards revisions are underway to provide detailed guidance on how to manage risk and hazards analytically.

"These revisions consider a fundamental difference between industrial machines and rides," says King. "In a ride, the [humans] inside the machine must be kept safe. So the implementation of safety systems is more complex than in industrial robotics and has to consider special scenarios for safely operating the equipment that do not exist in machines, such as evacuation."

Thorpe Park: The Swarm

Factoring in safety is an exercise in which Stilwell has had much experience over the last 12 months. Opening in the spring, Thorpe Park has announced its new ride, The Swarm, will be set in a disaster zone: the track arches out over a lake and will plunge riders into the burned-out shell of a Boeing 737, a helicopter and a derelict fire-truck.

Both the ride and Thorpe Park commanded tabloid headlines in January after test dummies were sent back with arms and limbs missing during test runs. The track took dummies too close to a dilapidated church, prompting the building to be reconstructed on a smaller scale. Publicity of the incident was rumoured by some as another in a series of publicity stunts by the park, which have included a request for urine donation to intensify the experience of SAW: The Ride and the sacking of six members of staff after an Ouija board séance took place on the same attraction during Halloween.

But Thorpe Park director Mike Vallis said he wanted the incident to highlight just how fine the line is between thrill or kill, offering a glimpse of how much planning and precision goes into creating the ultimate thrill-seeking experience. "We've pushed the boundaries to the absolute limit because 'extreme' is what our thrill-seeking customers demand. The ride-testing phase is absolutely crucial in ensuring extreme fun doesn't compromise safety, and we work with the very best teams in the world to ensure we reach the gold standard in safety."

"As health and safety is our number one priority this is an important process to the commissioning of any new ride and everything is overseen by an external body to ensure that the ride is fit for guests." Says Vallis, "This is the first time we have ever had any problems during testing and this is because we have tried to push the boundaries with how extreme we can make the near miss elements of this ride. We have now rectified the issues that we encountered by moving the plane wing and remodeling part of the church and ride testing is continuing safely."

The ride uses Rockwell Automation's safety and RS Logix 5000 software, primarily because of the safety requirements it fulfills. Rockwell Automation's GuardLogix PLC is also used to test the performance levels of The Swarm's anti-collision system.

"We've used an integrated safety system by Rockwell Automation before in 'SAW – The Ride', which was launched in 2009, but this is the first time we've used it with their POINT guard I/O," says Stilwell. "The use of this new technology allows the park to communicate safely via an Ethernet connection to devices in remote locations, for example on individual coaster braking sections."

The Swarm features a 'winged' car split into two parts straddling the central track like a pair of bat wings. Built by theme park giants Bolliger & Mabillard, it is one of only two rollercoasters like it in the world.

Stilwell explains that a winged coaster produces a different physical sensation, due to the car's position on the track. "Your body is in direct profile with the track. When the coaster does what's called a barrel roll, it induces higher g-force as you spin around. It's a completely different feeling from a normal coaster where the forces move you mainly back and forth or side to side."

As well as producing a new experience for the rider, a winged ride also has specific automation requirements, running on a special ASI network. Normally each lateral bar would be individually wired back to and monitored by the central system, but here each car is monitored as an individual network, with each lateral bar communicating internally with the car.

Integrating Ethernet has saved the park a considerable number of man-hours in cable-laying and cable maintenance, and it is in this technology that Stilwell believes the future of theme parks lies. Modern rides arrive from the manufacturer in pre-wired sections but, whilst in the past wiring couldn't begin until each section had been individually constructed, each module can now be wired to the next before plugging the whole system directly into an Ethernet connection. Built on reclaimed land surrounding Thorpe Park, infrastructure issues were avoided by digging the foundations of the ride into new soil, free of waterlines or underground power cables.

Robotic wizardry

As European core ride manufacturers continue to experiment with track-to-car ratios, across the pond even more innovative technologies are being pioneered under almost limitless budgets. American theme parks are perceived to be the jewel of the amusement park industry crown, with only the likes of affluent Asia and the Middle East rallying to challenge them. In 2010, all eyes were on Universal Studios, Orlando, when they announced the opening of their Harry Potter Wizarding World, complete with one of the industry's most controversial rides: Harry Potter and the Forbidden Journey.

Behind the ride is Robocoaster, an organisation composed of steel fabricators, university researchers, and automotive and industrial robot manufacturers. It was through the visionary direction and industrial automation knowledge of De Gol, president of the company, that the first industrial robotic arm was certified for use on a theme park ride in 2001.

De Gol was first inspired to integrate industrial robotics with entertainment back in 1999 when he noticed the European arm of the industrial sector seemed to have better insight into the requirements of the amusement rides than the amusement industry itself. During the early 1990s, the industrial sector was pioneering an abundance of innovative new safety systems, while the stagnant amusement industry seemed reluctant to trial new technologies.

"My premise was, why couldn't you use robots?" says De Gol, "Instead of having special-effect workshops building imitation robotics, why couldn't we use real robots?"

De Gol consequently quit his automotive engineering career with KUKA, previously Rolls-Royce, to pioneer the integration of robotics and amusements. Keen to disprove his doubters, De Gol produced the first generation of his robotic arm in 2001 with partner KUKA robotics. Dubbed the G1, the comparatively diminutive attraction was essentially a KUKA industrial robotic arm bolted to the floor and with passengers on one end.

When designing the first version of Robocoaster, De Gol used standard manufacturing robots as inspiration, factoring in higher safety levels. The end result, however, was far from economic. The proposed robot would have weighed as much as a tank, with extremely poor performance levels. Early versions were stopped mid-manufacture so the tools and aspects of the design could be altered, eventually producing a final model in 2001.

Universal's interest in their technology, at the time deployed on a small scale in shopping centres, was a real game-changer for Robocoaster. The previous G1 system allowed ride operators to integrate show systems such as media and AV into the motion envelope, provided no collisions occurred within the range of the arm. But Universal requested a robotic arm with four degrees of movement, mounted on a moving track, with a control system that would allow the robot to navigate passengers safely around obstructions and other motion-control systems.

This was a new challenge for Robocoaster as amusement rides are generally synchronised with show systems such as AV and CGI, meaning their processes are managed in linear-time measurements such as frames per second. Industrial machines, by contrast, are motion-based on linear, circle or point-to-point motion patterns. This meant the automation for the ride had to be adapted so that the ride was not only time-based, but also motion-based.

A robot future

De Gol is currently working on the G3, a high-speed version of the G2 robotic system in use on the Harry Potter and the Forbidden Journey ride in Orlando. The new version, ready by 2014, will be a thrill ride running at 30km/h, improving on the G2's 7.2km/h.

De Gol believes that the future of theme park rides lies in a new generation of robotics. Riding in automatically-guided vehicles (AGV) would provide each passenger with a unique entertainment experience, as the robots would be reactive. Instead of having one frontal wheel, or two wheels steering, four traction wheels would be integrated at the corner of each vehicle and kinematically mapped together. This would allow the AGVs to navigate safely at high speeds, simulating a variety of effects such as slides and skids.

"Vehicles could work together in platoons, with a combination of ground vehicles and drones interacting and acting out role plays with the passengers inside," says De Gol. "The whole system is also completely trackless, giving a wider creative scope. I think that AGVs will eventually have more of an impact on the amusement industry than robotics already has."

Future advancements will also be driven by the film industry and special effects. Ultra-high-definition, CGI and 360° immersive experiences have already become staple in the industry says Mark Woodbury, president of Universal Creative. "What people see on film has become the standard for what they expect in all their experiences, whatever their entertainment forum." *

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles