Tweet
Humor of a certain persuasion....
Washing machines: walk this way
How engineers finally solved the problem of washing machines that walked away.
For many years, Europe's washing machines tended to walk across a room, while America's did not. Daniel Conrad and Werner Soedel explained why, in a study called On the Problem of Oscillatory Walk of Automatic Washing Machines. Their explanation was recognised by authority figures for its power to inspire youths.
Conrad and Soedel, based at the School of Mechanical Engineering at Purdue University in West Lafayette, Indiana, published their work in 1995 in the Journal of Sound and Vibration. It was an instant classic.
The fear of ambling machinery resonated with the times. One could feel it in a 1995 Japanese science-fiction movie called Mechanical Violator Hakaider. Critic Jason Buchanan later described what happens once the title character, a cyborg, is loosed upon the land: "Once Hakaider sets on the path of destruction, there is little that can be done to stop him from destroying all of Jesus Town."
Washing machines of that era sometimes contained frightful things. A 1993 detective thriller called Vortice Mortale (English name: The Washing Machine) cinematically depicted a dismembered man inside an Italian washing machine.
Conrad and Soedel eschewed the sensational, restricting themselves to the engineering basics. "The problem of 'walk' in automatic washing machines is becoming more and more of interest to appliance manufacturers," they wrote. "The current trend is towards lightweight plastic and composite components. The reduction of mass associated with these changes in materials increases the possibility that a washing machine will walk."
In washing machines, the propensity to waddle is the consequence of a particular design choice. While steadfast American machines rotated their dirty clothes about a vertical axis, European designs typically made the internal machinery twirl around horizontally.
Conrad and Soedel saw this as a mechanical and business blunder. They wrote: "The horizontal-axis washer has innate unbalance problems associated with the design. This unbalance can typically create a force in excess of 19 kilonewtons during the spin cycle."
Four years after the publication of On the Problem of Oscillatory Walk of Automatic Washing Machines, two officers at the US Military Academy in West Point, New York, used it as a major source for their paper called Basic Vibration Design to Which Young Engineers Can Relate: The Washing Machine.
Lieutenant Colonel Wayne Whiteman and Colonel Kip Nygren pointed out: "Virtually every campus has laundry facilities for students. Most students are therefore familiar with the unwanted vibrations that occur when an unbalance of clothes accumulates during the spin cycle."
Young engineers thrill at bad vibrations. Keying on that, Whiteman and Nygren sketched out, in terms designed to resonate with their audience, the story of how to prevent oscillatory walk. These terms are lyrical, if you are a certain type of engineer, and perhaps someone will use them in a hip-hop song: Mass of the Entire Machine; Mass of Inner Housing and Rotating Drum; Mass of Unbalanced Clothes; Coefficient of Static Friction with Floor; Radial Distance to Unbalanced Clothes; Spin Speed; Suspension Spring Constant; Suspension Damping Ratio.
• Marc Abrahams is editor of the bimonthly Annals of Improbable Research and organiser of the Ig Nobel prize
http://www.guardian.co.uk/education/...shing-machines
Washing machines: walk this way
How engineers finally solved the problem of washing machines that walked away.
For many years, Europe's washing machines tended to walk across a room, while America's did not. Daniel Conrad and Werner Soedel explained why, in a study called On the Problem of Oscillatory Walk of Automatic Washing Machines. Their explanation was recognised by authority figures for its power to inspire youths.
Conrad and Soedel, based at the School of Mechanical Engineering at Purdue University in West Lafayette, Indiana, published their work in 1995 in the Journal of Sound and Vibration. It was an instant classic.
The fear of ambling machinery resonated with the times. One could feel it in a 1995 Japanese science-fiction movie called Mechanical Violator Hakaider. Critic Jason Buchanan later described what happens once the title character, a cyborg, is loosed upon the land: "Once Hakaider sets on the path of destruction, there is little that can be done to stop him from destroying all of Jesus Town."
Washing machines of that era sometimes contained frightful things. A 1993 detective thriller called Vortice Mortale (English name: The Washing Machine) cinematically depicted a dismembered man inside an Italian washing machine.
Conrad and Soedel eschewed the sensational, restricting themselves to the engineering basics. "The problem of 'walk' in automatic washing machines is becoming more and more of interest to appliance manufacturers," they wrote. "The current trend is towards lightweight plastic and composite components. The reduction of mass associated with these changes in materials increases the possibility that a washing machine will walk."
In washing machines, the propensity to waddle is the consequence of a particular design choice. While steadfast American machines rotated their dirty clothes about a vertical axis, European designs typically made the internal machinery twirl around horizontally.
Conrad and Soedel saw this as a mechanical and business blunder. They wrote: "The horizontal-axis washer has innate unbalance problems associated with the design. This unbalance can typically create a force in excess of 19 kilonewtons during the spin cycle."
Four years after the publication of On the Problem of Oscillatory Walk of Automatic Washing Machines, two officers at the US Military Academy in West Point, New York, used it as a major source for their paper called Basic Vibration Design to Which Young Engineers Can Relate: The Washing Machine.
Lieutenant Colonel Wayne Whiteman and Colonel Kip Nygren pointed out: "Virtually every campus has laundry facilities for students. Most students are therefore familiar with the unwanted vibrations that occur when an unbalance of clothes accumulates during the spin cycle."
Young engineers thrill at bad vibrations. Keying on that, Whiteman and Nygren sketched out, in terms designed to resonate with their audience, the story of how to prevent oscillatory walk. These terms are lyrical, if you are a certain type of engineer, and perhaps someone will use them in a hip-hop song: Mass of the Entire Machine; Mass of Inner Housing and Rotating Drum; Mass of Unbalanced Clothes; Coefficient of Static Friction with Floor; Radial Distance to Unbalanced Clothes; Spin Speed; Suspension Spring Constant; Suspension Damping Ratio.
• Marc Abrahams is editor of the bimonthly Annals of Improbable Research and organiser of the Ig Nobel prize
http://www.guardian.co.uk/education/...shing-machines