15th Symposium on Lift and Escalator Technologies

Industry leaders come together to share their expertise. 

On September 18 and 19, the movers and shakers of the lift industry came together at the Kettering Park Hotel & Spa in Northamptonshire, U.K. for the 15th annual meeting of the Symposium on Lift and Escalator Technologies to put forward and present their academic papers on ideas and solutions to help the vertical-transportation (VT) industry on its constant evolution of new technology.

The symposium drew speakers and delegates from all over the world including the U.S., Canada, Japan, India and Jordan who were all there to share their expertise and listen to the experts in their fields, respectively.

It was a great two-day event with lots of great presentations, and although there was a seriousness to the air and every paper was listened to intently, there was also laughter, banter and camaraderie among the delegates, speakers and organizers. Every presentation drew questions at the end which were expertly and thoroughly answered by presenters.

The doors opened at 8:30 a.m. for registration, and tea, coffee and refreshments were served to the incoming delegates. There were smiles all around as familiar faces met each other for the first time in a long time, joking about who was looking the eldest and talking shop about the latest technology on the market over a coffee. 

The proceedings started at 9:15 a.m. sharp. Attendees were greeted with a big smile and a warm welcome by the delightful and graceful Elizabeth Evans of Peters Research to this industry-leading event. 

First up to the lectern was Dave Cooper, MBE, from LECS UK/UAE to welcome everyone to this year’s event and introduce another iconic figure within the industry: California native Dr. Rory Smith for his presentation on escalator safety.

Smith — “New Technologies That Improve Escalator Passenger Safety” 

Smith has more than 50 years’ experience within the VT industry, starting off as a sales engineer trainee at Westinghouse Elevators in Los Angeles in 1969 and holding numerous titles throughout his distinguished career, latterly being senior leadership roles for Thyssen Krupp Elevator around the world. Smith is a consultant to Peters Research and also a visiting professor to Northampton University.

Smith started off the morning session with “Innovative Technologies That Improve Escalator Passenger Safety.” Smith talked about how most accidents on escalators occur with the elderly, mostly those over 65 years old, and with commuters taking luggage onto the escalators instead of using the lift.

The Guangzhou Metro System was spoken about briefly regarding the survey it had completed on escalator safety. This was a survey conducted using the Haddon matrix procedure that analyzed 967 escalator accidents, taking into account all mitigating factors, from human error, machine error, age, gender, environment and, importantly, time of day. It was also noted that most accidents happened in the off-peak period and were mostly due to age of the riders. The survey can be found online.

The factors that can help with the reduction of accidents could be variable speed drives or VFD. This is due to the dynamic velocity control with dynamic braking or, in other words, the braking resistors on the drive that collect the dissipated energy from the motor as it provides braking torque to stop the motor. This then means that any wear on the brake pads would be non-existent.

Reduced speed when exiting the congested escalator can lessen the risk of people falling or tripping. The Step/Skirt Performance Index (ELEVATOR WORLD, December 2019) test is a test to measure the gap between the skirt/step for the potential of an entrapment. This can be measured using a Physical Measurement Technologies’ (PMT) device, which can be used to find problems with steps, the track and the skirts. 

Skirt obstruction devices are used to detect debris or entrapments between the skirt and step and then shut the escalator down when it approaches the comb plate area. A step switch is required for each escalator step in the U.S., Canada and Hong Kong.

The step upthrust device is a device that is electrically connected into the safety circuit and sits just under the comb plates. Should the step decide to dislodge, the switch will activate and stop all movement; this prevents any possible step pile up. A possible bigger transition period on the escalator and also a bigger demarcation zone would create a safer egress and regress zone.

Matthew Davies — “From a Bell on a Rope to VoIP: The Evolution of the Lift Alarm in the U.K.”

Davies started off talking about the history and evolution of the U.K. telephone system from the early days of the Government-owned General Post Office (GPO) and exchanges alongside the separately controlled Kingston upon Hull Telephone system, which kept its own license to trade and resisted a buy out from the GPO.

In 1969, GPO ceased to be a Government department controlled by the public purse of the treasury and made the switch to become a public corporation to control its own autonomy, and then changed again 12 years later when it became British Telecom.

By the late 1970s, phones in elevators started to be mandated and new European codes were brought in. It was typically a normal phone with a set of instructions within a cabinet built into the inside of the lift car. All lift installers had to agree to comply with the new rules.

By the mid to late 1990s codes were changing again — in 1997 and 1998 with the latter date declaring that all elevator alarm systems had to have a two-way voice communication system. As time went on, most elevator companies started using Autodiallers integrated into the lift car with dual-tone multi-frequency (DTMF) signaling.

The new system meant you only had to press one button, and there were less instructions. This was due to the use of the DTFM system, which doesn’t just use a voice call. It also sends data to the lift company server, which then brings up all the details about the elevator the people are stuck in, the building and address, etc.

Autodiallers have evolved and can now also send three-day test calls and remote phone call configuration.

The end of the Public Switched Telephone Network (PSTN) copper lines was spoken about with the new date for them to be switched off as January 2027, which means the transition to VoIP (Voice over Internet Protocol) or a Global System for Mobile Communications (GSM) signal.

More innovation was also spoken about with regards to GSM signals or lack of due to specific things like buildings blocking the signal from reaching the telephone mast, network congestion in large, gathered areas like football stadiums or security services commandeering the mobile network services.

Daan Smans — “Modelling Failure Detection of Lift Doors Through Sensor Fusion”

Smans talked about everything Internet of Things (IoT) connected to lift doors, explaining that at the core of the building are the elevators and that the value of the building is reliant upon these elevators working, as it is not viable to have extra elevators just to compensate for downtime.

The multiplicity of robust elevator doors throughout installation is one of the biggest safety aspects of the installation along with modern-day codes and the initiation of door lock monitoring into them.

The most common downtime that occurs from an elevator is through a problem with the lift doors, and that is why there is now a shift towards IoT, which combines different data sources to detect what has gone wrong, ”i.e., optical sensors, accelerometers, gyroscopes, temperature, humidity and barometric pressure sensors.” These sensors can indicate to the service engineers where to focus when attending a call out or a pre-planned maintenance. They can give real time and historical data and indicate to all the health of the doors on a floor-by-floor basis.

Thomas Ehrl — “How To Transfer Complex Knowledge in Distance”

Ehrl is a well-experienced professional who worked for Thyssen Krupp, now TK Elevator, at the Rottweil test tower in Germany. His job whilst there was to improve the ride quality of the Transrapid maglev (derived from magnetic levitation) lift. He now works for the chemical company Evonik. He presented a paper about the transfer of knowledge that was a seven-year research project. It consists of 241 pages and includes a model for knowledge transfer that came about through many interviews and included 420 participants. 

What is important for successful transfer knowledge, he asked? The learning preference is important as people learn differently: Some prefer theories, some prefer verbal and some prefer visual, but what is needed is a clear instruction design and the tools needed to deliver it. The technology we use to deliver the transfer of knowledge was mentioned with AI, 3D technology and social networks becoming prevalent in society and also the idea of an interactive website. 

Paul Burns — “Blackout: Exposing the Hidden Risks of Battery Failure in Lift Passenger Emergency Systems”

Burns spoke of the hidden risks in battery-backed emergency systems and explained that tests had been completed on 2,600 lifts and 18.5% of those had defective back-up batteries, and 70% of the failures happened at commercial and retail offices. 

A huge failure occurred with an OEM having eight times as many failures on their own brand than there was with a third party, and cloud-based monitoring also provided data that evidenced that 63%-73% of failure was down to brand failure. Mandatory tests were asked for with the main power isolated and for any lifts that fail to be isolated until the battery is replaced.

One thing is for sure in the lift community — for an industry that’s so huge, it’s also a tight knit one. I’d say the six degrees of separation rule could definitely be done in less.

Micky Grover-White — “Modernizing Model Lifts and the Implications”

A model lift is a mass manufactured lift that has its own limited codes with respect to its size, speed and load. So modernizing the lift means the parts being modernized need to conform to the same specifications, and the CE mark should be retained. However, adding extra weight to the car by adding a car re-line, for example, and then having to re-balance with extra weights in the counterweight mean extra weight on the sheave, which means a new machine may be required. At this point, the design of the original lift has changed, and it would lose its CE mark. He also spoke about commissioning and consequences after the lift has been placed back into service.

Smith — “Bowtie Diagrams, a Tool To Improve Risk Assessment”

Bowtie diagrams are a risk assessment used throughout the industry to assess the severity of harm and probability of occurrence.

ISO 14798 is the International Standard for lifts and escalators, and its purpose is to help assess the risk so correct decisions can be made. Bowtie diagrams are required by the Civil Aviation Authority and Network Rail, and they were even adopted by the Royal Dutch Shell Comp. after the Piper Alpha Disaster 1988. They are defined as a quantitative method that uses a statistical analysis with a numerical measurement.

Lunchtime

With the morning session drawing to a close, it was time for the group photo in the beautiful gardens of the hotel. Once the posing and smiling for the camera were complete, it was time for everyone to fill their bellies with the delicious lunch laid out by the incredible hosts. There was a lot of mingling and networking of consultants, facilities management, lift companies and suppliers alike, many of whom have been in the industry for many years and already knew each other well, while others were just meeting for the first time. 

One thing is for sure in the lift community — for an industry that’s so huge, it’s also a tight-knit one. I’d say the six degrees of separation rule could definitely be done in less.

TAK Mathews — “Unravelling Destination Control Systems – A Practical Perspective”

Mathews, a cheerful character from Mumbai, presented a paper based on more than 25 years’ experience in dealing with the Destination Control System (DCS) in India. He explained that, at first, it wasn’t well received due to machinery problems and users not really knowing how to use the new system. However, once a review was completed and different calculations were used to achieve better optimization with grouping the cars together, then the DCS had more success, he produced more data showing the ups and downs of DCS in India.

Lutfi Al-Sharif — “Estimating the Traffic Mix in a Building by Analyzing the Stops Data per Round Trip”

Al-Sharif spoke about trialing lifts by testing them with a million stops on the up stops and on occupant floors and with a mixture of all other stops in a synchronized test. Tested in the up peak and down peak also, the data collected for this paper will be used to create a machine learning app that will be able to estimate the mixture and intensity of traffic coming into the building.

Richard Peters — “Evacuation Dispatching: Strategies To Get as Many People Out as Possible as Quickly as Possible Using Lifts”

Peters paper spoke about modern day dispatching and how it is optimized to create the shortest wait time possible for those waiting for the lift and how it can be utilized in an evacuation to empty the building as quickly and safely as possible.

By using clever dispatching, tests were completed via up peak and down peak, using the highest reversal time and the calculations were analyzed, along with the design strategies like grouping floors and dividing buildings into sectors.

A full evacuation of the building at the same time means speedy evacuation could be secured by risk-based dispatching and the prioritizing of the risk on each floor. New user interfaces were spoken about being needed to help communicate with and reassure people due to the panic and psychological stress the situation could be having on them.

Kristian Farr — “Theoretical Evaluation of Evacuation Lift Capacity Assessments”

Farr started his theoretical paper by talking about the London Plan Guidance, which is a policy introduced by London’s mayor to assess the fire safety and evacuation procedures at the planning stage and not the preconstruction stage of a building. The guidance states the buildings should “be designed to incorporate safe and dignified emergency evacuation for all building users.”

The plan and codes of practice state that one firefighting lift per core or more is to be used in the designated fire plan, depending on the capacity of the building. Farr also spoke about a phased evacuation strategy of a 34-storey building and theoretical traffic analysis studies that estimate the time taken to evacuate a building in phase one of an evacuation using the London Plan.

Stefan Voth — “Car Deceleration During Buffering Process of Lifts”

Voth spoke about the stroke, force and controlled stopping that the buffers give to accelerating elevators and what mechanical values are needed for that. He spoke about how the buffer uses kinetic energy to dissipate the force during the buffering process, creating safe stopping against the speed and mass of the lift and that all buffering processes have to adhere to the rules of EN 81–20.

Ionna Sfampa — “Design of a Compact Air Conditioning Unit Using CFD and Thermoelectric Coolers”

Sfampa presented this paper regarding a very clever compact air conditioning unit using computational fluid dynamics (CFD) and thermoelectric coolers. Many aspects were considered regarding noise, lift car installation and the time taken to cool the cab. The size of the cooler is 30 cm X 10 cm, and it uses 10 Peltier elements to create a heat exchange using 50 W of power. The heat generated from the cooler dissipates into the lift shaft while the cool air enters the cab. The research is co-funded by the European Regional Development Fund and Greece.

Keisuke Minagawa — “Study on the Seismic Response Analysis of Lifting Ropes in the Development of Digital Twin Technology to Reduce Earthquake Disasters in Residential Buildings”

Minagawa started by stating that 43.5% of the housing in Japan is apartment buildings, and a strong earthquake could end up shutting down 20,000 lifts. The shutdown of these lifts would have a huge impact due to the aging population of Japan.

The digital twin method is a simulation system which creates a real-world scenario based in a virtual world. It is used to test worst-case scenarios with earthquakes. The analysis from these tests is used to calculate the equation of motion on ropes based on an earthquake wave, the vibration mode of ropes and the seismic analysis of the ropes.

“Artificial Intelligence Embedded Image Process-Based Fatigue Life Determination on Wire Ropes Subjected to Bending Loads”

This paper was written by Mohsen Seyyedi, Adem Candaş and C. Erdem İmrak but presented by Al-Sharif on behalf of the authors. 

The paper is based on the constant bending of steel wire ropes and how the stresses and strains can limit their lifetimes. The sheave to rope diameter should be 40 to 1. If this equation is not used, then reverse bend happens on the ropes, which may mean the ropes have a life of only 18 months. Twenty-four experiments were conducted with strain gauges and AI to measure and collect the data of the strain of the rope. Wire fatigue occurs primarily through wire fractures in outer strands, and the number of broken strands should determine when the ropes should be replaced.

Stefan Kaczmarczyk — “The Strength and Design Criteria for a Lift Guiding System Revisited”

The guide system is one of the most important interfaces within the shaft. It guides the lift up and down the shaft, so it is imperative that it stands the test of time and is solid and robust. Kaczmarczyk talked about the code EN 81-20-50; about buckling, bending and deflecting; and that studies have been carried out on the guide brackets and how it is advised they should now be spawned closer together. A multi-span beam model used to determine the specification for guide rail bending, various boundary models and the issue of providing accurate data for strength evaluation are discussed and appraised in the paper.

Event Conclusion

Farr won the Gina Barney award for speaker of the Symposium for his theoretical paper on the evacuation of a 34-floor building. Also, acknowledgment was made to Nick Mellor for his incredible stability and stewardship as chair of the Lift and Escalator Industry Association (LEIA); he will be passing the baton on to someone else. Kaczmarczyk was also acknowledged by Thomas Ehrl for his incredible mentorship.

As the two-day event drew to a close, we reflected on some superb presentations that took place. Innovation is what keeps our industry moving forward, and we need that to create a faster and safer experience for all those who ride in the lift on a daily basis; there were certainly some great ideas and innovations. In the final speech, Peters and members of the Symposium management team thanked everyone for their attendance, input and for making it another great event with industry changing papers and theories.