Timid escalator riders who look twice before taking their first step will soon have something new to worry about. After years of trying, Mitsubishi Electric has developed a moving staircase that carries passengers not just up or down in a straight line but through a graceful, sweeping arc. The first two circular escalators will be installed next March in a shopping mall in Tsukuba, Japan. Cost: $325,000. A pair of conventional models, by contrast, costs $100,000.
The idea of a circular escalator seems simple enough, but the design problems were daunting. The challenge was to lift passengers up and around...