Technology and services inside High Roller Observation Wheel communications

Technology and services update on engineering the communications for the project includes more diagrams, more application and project details, and a list of Moxa communication equipment used, from the engineering experts involved. See related application update article.

By Oliver Wang August 19, 2014

Setting a new Guinness World Record for observation wheel height, the High Roller provides passengers with a smooth 30-minute ride with unimpeded 360-degree views of the Las Vegas skyline. Video screens show passengers their cabin’s position as it travels around the wheel and are also used for in-cabin entertainment programs. The IP-based communications infrastructure makes every aspect of the control and emergency systems accessible to operators at the central control room, enabling the High Roller to meet the highest standards for operational reliability and passenger safety.

Communications related products and supplier services referenced are from Moxa.

Equipment combined high-quality design and construction and special features for industrial performance and reliability. With years of experience in wide temperature networking equipment and fanless operation, the equipment ensured years of uninterrupted communications, even in the punishing Las Vegas heat. The dual redundant network topology helped ensure an exceptionally reliable wireless connection that suffers no performance loss even when faced with the heavy wireless interference from surrounding casinos and hotels.

Perhaps even more valuable to the project was the technical expertise demonstrated by the supplier team in IP communications and industrial control systems. The communications component supplier understood how to apply networking technology to industrial control systems and became a critical asset in later stages of the project. The high complexity of the network and unique features of the site introduced unanticipated issues that were extremely difficult to resolve, especially with the number of systems and equipment vendors in place. 

Networking complication

"We came to a point where the networking issues were threatening to delay this very high-profile project," according to Randy Printz of Themed Development Management, project manager overseeing design and deployment of the High Roller. "The network was one of the most critical aspects of the system. All of our safety critical data is carried on this network. If the network doesn’t work, we’re not operating."

The communications provider’s field application engineers had extensive expertise with control systems and networking technology to assist with the project.

"We reached out to the team for help, and they came out on very short notice, spent a considerable amount of time working side by side by with us, on more than one occasion," said Printz. "They were incredibly experienced and professional, and were able to work cooperatively with us alongside our equipment vendor, primary suppliers, and contractors to not only resolve these issues, but help us achieve extremely high network reliability."

The communication supplier engineers assessed the entire communications infrastructure, not just the parts involving its hardware. Based on their recommendations, some additional steps were taken that helped address all communication issues and ensure that the control network was extremely reliable. No other component supplier provided this service, which proved essential in the ultimate success of the project.

Specialization in industrial networking was key, said Lance Heywood, integrated control system designer at Heywood Engineering, one of the contractors working on the project. The networking manufacturer staff members are familiar with industrial equipment and know how to connect to things like programmable logic controllers (PLCs). "They understand the difference between reliability in a business setting and reliability when it is a life safety critical system," Heywood said.

Project challenges

System integration was an important part of the project, according to Printz, the High Roller project manager. He said, "We had a number of unusual and unique situations. We were dealing with two prime contractors. Schwager Davis handled the integrated ride control system, and Leitner Poma handled the passenger cabins, and both needed wireless communications systems. With a project like this, you have fixed pieces and you have moving pieces, and they need to communicate wirelessly to each other.

So we were looking for a system that could meet the needs of these two suppliers. We were looking for commercially available products. We wanted to stay with common, known components, not be the guinea pigs for a brand-new unproven technology. We were also looking for engineering expertise. This was a unique application and we knew we were going to need significant contribution in engineering support and after-sales service." Based on these criteria, Printz said, the communications supplier was chosen. "By the end of the project, they had met and exceeded our expectations in nearly every way."

Jon Mauch, project manager at Leitner-Poma, said he had previously worked with the communications supplier on ropeway projects with positive results.

Mauch said, "There was an importance level of having a highly reliable network. The network was an essential part of a life safety application so redundancy was critical. The only way that the cabin communicated with the ground controller, whether it was for control or for emergency communications, was through the network. The industrial control network on this wheel was to be transmitted using various methods: fiber, coax cables, Wi-Fi, and wireless jumps through the rotating components. Ultimately we ended up with 2 jump points per cabin, 56 jump points just for the cabins. This was going to be in an area where we hadn’t been before. It was far more complicated than the type of installation we normally see, especially with the number of jump points involved."

Having a company with networking and control system equipment familiarity "proved to be a critical advantage when we needed it most," Mauch said.

Heywood had experience with the communications supplier with networking equipment for people-mover projects. This was the first network communication that also included a services offering. 


Read more on the first page, including a 3D diagram.

High Roller challenges

Printz said one of the biggest challenges was designing and deploying the network. "According to one of the field engineers," Printz continued, "the network that we were putting in place was the most complex industrial control network they had ever seen. In addition, this was to be installed outdoors in Las Vegas, a very difficult environment; 60 wireless networks needed to function simultaneously and seamlessly up to 18 hours a day without fail, in a fairly difficult environment, in temperatures ranging from 12 to 120 degrees, in high winds, with large quantities of dust, and a lot of radio traffic. The equipment would be 200 to 500 ft in the air, and would be in constant motion and constantly changing orientation. No one had ever done this kind of thing before. That was the technical challenge.

"Working closely with our primary contractors and suppliers, we developed the best engineering solution we could. However, we encountered numerous communications issues on-site that were extremely tough to diagnose and address. For example, it turned out that there was significant wireless interference on the 2.4 Ghz spectrum, so we had to go to 5 Ghz. With all the different types of equipment and vendors involved, it was an enormous challenge simply determining where communication issues were occurring and why.

"We came to a point where the challenges of setting up the networking issues were threatening to delay this very high-profile project. The network was one of the most critical aspects of the system. All of our safety critical data is carried on this network. If the network doesn’t work, we’re not operating. You can understand the pressure we faced."

Printz said the communications provider, when asked, came out on very short notice and "spent a considerable amount of time working side by side by with us, on more than one occasion." Engineers sent were "incredibly experienced and professional, and were able to work cooperatively with us alongside our equipment vendor, primary suppliers, and contractors to not only resolve these issues, but help us achieve extremely high network reliability." 

Added help provided

Mauch said, "This might be one of the most complex systems any of us had ever seen put together. It needs a major level of reliability, and we were under fire when we were unable to successfully start the network. There was a huge amount of Wi-Fi interference from the surrounding hotels and casinos, and we had exhausted all our efforts and technical ability trying to overcome that and establish the industrial control network."

Having highly qualified engineers available in a hurry at a critical juncture of the project "Made the difference-they stepped in when we needed it and helped us get the system going," Mauch said.

Heywood said the sheer size and scope of the High Roller network, and the amount of wireless that was used, made it particularly challenging. The communications supplier was particularly responsive "early on during the factory testing. We needed some functionality that wasn’t available on the off-the-shelf product," Heywood said, and that functionality was delivered within 24 hours, "allowing us to move forward." 

Service reliability

Printz said, "In as complex a system as we’re operating, it’s never exactly clear which components are having issues. In a situation like this, it’s extremely rare for a manufacturer to step up and commit to solving an issue when it’s not even clear that their hardware is at fault." Those involved "put tremendous hours out in the field" and responded to the urgency. "Even when it turned out that their equipment was 100% functional, they helped us assess the network and made the right recommendations that got everything up and running to the high degree of reliability."

Mauch said, "When it comes to networks, and wireless in particular, it can seem like smoke and mirrors at times. You can’t touch it. It’s a mystery." Having everything explained "at a basic level, without overwhelming me with technical terms…. I’ve had conversations with control engineers where I might as well not even be in the room."

Heywood said that field application engineers were huge assets beyond their own products, with knowledge "of networking in general and of the PLCs and other equipment that we were dealing with," including familiarity with "industrial equipment and know how to connect to things like PLCs…. There was a huge life safety critical element involved. When something goes down, it’s not just a loss of data, it’s a halt of all operation in order to safeguard human lives." 

Huge effort

"This was a gigantic effort," Mauch said, "involving a large number of independent groups. Even the control network was being developed and installed by more than one entity."

Heywood added, "Experience in connecting to different types of equipment was key."

High Roller network products

Moxa products used in the High Roller project are:

  • AWK-3121-T IEEE 802.11a/b/g industrial wireless access point/bridge/client
  • AWK-4121-T 802.11a/b/g outdoor wireless access point/bridge/client
  • AWK-4131-T 802.11a/b/g/n outdoor wireless access point/bridge/client
  • EDS-510A-3GT-T industrial managed Gigabit Ethernet switch
  • MXview-1000 network management software
  • PT-7728-R-24-24 28-port managed rackmount switch with ruggedized Gigabit SFP modules
  • TN-5510-2GLSX shock and vibration-rated managed Ethernet switch
  • EDR-G902 Gigabit network security router
  • EDS-728 28-port managed Ethernet switch
  • EDS-828 28-port Layer 3 managed Ethernet switch

– Oliver Wang is marketing communications manager, Moxa. Edited by Mark T. Hoske, content manager, CFE Media, Control Engineering,

ONLINE extra

Also read "World’s tallest observation wheel: industrial communications" for more application details below.

Like super tall structures? See a related article covering engineering challenges in supertall buildings below.

Author Bio: Oliver Wang is the product marketing manager for edge connectivity at Moxa.