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It's never a good idea to maim your customer

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10/14/2010 09:49 PM EDT

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Salio
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re: It's never a good idea to maim your customer
Salio   11/3/2010 5:03:37 AM
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I think the heading of this article should have been "Build in safety futures prior to customer demo". I mean how come someone from the plant didn't do what this VP had done? This could have been avoided had someone actually poked around in the system. The embarassment could have been prevented.

mr_bandit
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re: It's never a good idea to maim your customer
mr_bandit   10/26/2010 1:58:18 AM
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Jerry Weinberg tells a story where he was brought in to find a problem with an IBM mainframe nobody else could track down. The mainframe would glitch or reset at odd times. He started watching. He noticed the problem occurred when an operator touched the keyboard, but only when she walked up and first sat down, and the first thing she touched was the keyboard. She was wearing a skirt and nylons - conforming to the dress code. The dress code was modified for female operators.

kalpak
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re: It's never a good idea to maim your customer
kalpak   10/21/2010 4:56:25 AM
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"Member of upper management" syndrome strikes again! Next time, use your company's VP/ Chairman/ CEO for finding such bugs. Better still use your CFO. After such a "demo", the CFO will never say no to a budget for test equipment.

sharps_eng
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re: It's never a good idea to maim your customer
sharps_eng   10/20/2010 8:09:57 PM
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Too often a designer concentrates on the main performance arc, in this case the motor drive end-to-end. The safety features are then bolted on afterwards to constrain the motion to credible limits. Safer method is to define the safe envelope first, then shrink it until the remaining degrees of freedom allow only the arc actually needed for the function.

araasch
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re: It's never a good idea to maim your customer
araasch   10/18/2010 8:44:35 PM
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Another thing that should be considered is a overspeed shutdown mode, assuming that in normal situations the drive motor is not expected to ran at maximum speed. This same type of test could have saved several lives in a radiation dosing machine which failed due to a software bug, thereby delivering a dose which was several orders in magnitude above the maximum therapedic dose (and therefore relatively easy to make a hardware test for). This basicly comes down to having a machine which has hardware sanity checks in it which cause it to go into a safe mode if something is detected that indicates a out-of-normal situation. Important whenever life or limb depends on the proper operation of a device.

agk
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re: It's never a good idea to maim your customer
agk   10/17/2010 11:10:11 AM
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Reading this article i recollect my college days. We made a lowpass and hugh pass filter and added a mic and a relay and simple logic to switch to bulbes from the output of the filter.The bulb connected to HPF named as woman and LPF as man. Most of the times during the exhibit of the project with voice from the students this was triggering properly . Except for one student. Whenever that student touches the microphone both the bulbs glow without uttering a single word. That student had a high static electricity always in her hands.Great natures gift and wonder !!!

WKetel
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re: It's never a good idea to maim your customer
WKetel   10/17/2010 1:08:18 AM
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This is an interesting case of what looks like inadequate connection between things that should all have been tied to some power common. It would indeed be very educational and possibly interesting to trace the exact mechanism of the failure

WireMan0
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re: It's never a good idea to maim your customer
WireMan0   10/15/2010 7:37:21 PM
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Mt brother had a similar experience while attending the National Computer Conference years ago. He walked up to a rack-size hard-drive system and touched the case. The resulting electrostatic discharge caused the hard-drive motor to stop spinning. When we went by the booth later that day technicians were still working on it. At least no one got hurt.

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