NYC Variable-Speed Escalators Off to Less-Than-Smooth Start

A plan by NYC to turn over 35 subway escalators to variable speed operation — all in the name of green because of the energy savings — began in fits and starts, literally. So reports the NYT in an article about the debut of the new escalator operating mode earlier this month.

“According to signs posted by the authority each escalator was equipped with an infrared motion sensor that ‘sees’ customers approaching and ‘tells’ the escalator to speed up…late in the day, officials acknowledged that only 22 of the 35 escalators at the four stations were working as intended.”

See a video of a variable speed escalator in correct mode.

While it’s not clear what the problems were, variable speed motor control (first introduced in the 1930s) is extremely reliable when designed properly. What may not be so reliable is how passengers first respond to the new technology — as evidenced by the photo above, which shows on launch day a passenger, unfamiliar with escalators, who fell when the speed increased and remained seated for the ride up.

3 Comments

1. 
   MSB
   August 27, 2008

   On the Munich Underground many of the escalators only start when you approach them, and are also tidal flow and can go up or down. So you cant easily make a run for it down your favourite escalator, it might be going the other way.

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2. 
   Bernard Green
   August 27, 2008

   Oh dear,
   Another not very well thought out idea.
   Varying the speed of an escalator when there are people standing on it. Did no one consider the effect this “earthquake” effect would have on the people standing on it ? Or was the consideration made from the experience of other transport systems where people expect acceleration and deceleration and have suitable restraints ( seats ) or points to hold onto that are suitable ABOVE the centre of gravity of the person’s body and therefore, with a fulcrum at the feet, able to allow the person to control of their motion realtive to the vehicle. In short escalators do not have an effective way to prevent people falling over when the stair case accelerates. DANGEROUS on any stair case.

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3. 
   Tim Asquith
   August 25, 2010

   You were right the first variable speed escalators were installed around the 1930s in London Underground. The escalators were in central London area, and were designed for rush hour.
   As people stood on the escalator it measured the load on the DC motor (600v) and stepped up the speed. Non load speed about 85ft per second to 110 ft per second.

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