Clean-air
allies: Rickshaws get a lift 
By P. Weiss
In developing countries, most people can adopt a new technology only if it's cheap. Keeping low cost paramount, a team of Indian and American engineers has redesigned a widely used, nonpolluting human-powered taxi—the cycle-rickshaw. In cities such as New Delhi in India and Dhaka in Bangladesh, hundreds of thousands of such rickshaws ply the roads. Unlike the light, strong, metal-alloy bicycles with 10 speeds or more that abound in Western countries, cycle-rickshaws remain largely single-gear bruisers weighing up to 90 kilograms unloaded. The redesign team trimmed 38 percent of that weight by switching to a tubular frame and streamlining the carriage. The engineers also changed distances between wheels to improve handling and provided at least two speeds. "We couldn't increase the bore of the human engine, the human heart, so we had to make the machine more efficient," says Matteo Martignoni of the nonprofit Institute for Transportation and Development Policy in New York City. The team also tested and rejected more complex and costly improvements, such as shock absorbers and differential gears. Air-pollution damage to the Taj Mahal in Agra has prompted a ban on gas-powered vehicles from a wide swath around the building. The institute and cosponsors of the redesign hope to use the ban to boost the fortunes of the environmentally friendly rickshaw, which offers a livelihood to many extremely poor people. Late last month, the team paraded some four dozen of the first batch of machines past the Taj Mahal. About 30 of the $100 vehicles have already been sold by two Indian firms.
From Science News, Vol. 156, No. 21, November 20, 1999, p. 333. Copyright © 1999, Science Service. |
