January 31, 2007

Perhaps They Should Have Tested More - Coast Mountain Bus Company

The power steering doesn't work after going through intersections.

In the last generation of these buses, 80 percent of the braking power was sometimes lost.

Well - at least they are still under warranty!

Steering woes sideline new buses 
William Boei
Vancouver Sun

Wednesday, January 31, 2007

GREATER VANCOUVER - Coast Mountain Bus Co. pulled at least 39 new trolley buses off the road Tuesday because of problems with their power steering, TransLink said.

A TransLink representative said the problem appears to be a software glitch affecting the buses' sophisticated electronics that should be quick and easy to repair.

In the meantime, bus riders on trolley routes may find themselves waiting longer than usual for the next bus.

Many of the New Flyer buses, which were delivered late last year, have problems when they pass couplings in the overhead wires, especially at intersections.

There is a brief moment when the trolleys lose contact with one section of the coupling before they make contact with the next section.

"They go on battery power for that one brief moment," said TransLink's Drew Snider.

"What's happening with the new buses, it's been discovered, is that the power steering sometimes hardens up" after the momentary loss of power, making the buses difficult to steer, Snider said.

"It's under warranty," he added. "New Flyer has sent somebody out here who's going to be in town tonight [Tuesday] and then [this] morning they'll be getting to work on getting this fixed."

Snider said TransLink hopes to have the buses repaired within a day or two, and is looking for other buses that can plug the gaps in service.

TransLink has few spare buses on hand because it hasn't been able to afford to buy enough to keep up with demand.

"We're working on that," Snider said. "We've basically retired a lot of the old trolleys, and the ones that are retired are not fit for service.

"We still have some older trolleys that can go into service, we're trying to pull some diesels in, we're just seeing where we can get some extra resources for this afternoon's rush hour. Right now we don't know, exactly."

Jim Houlahan, a bus driver's union leader, later said Coast Mountain told him 49 buses were eventually taken out of service.

Houlahan, vice-president of CAW Local 111, said Coast Mountain intended to take out only problem buses, but learned Tuesday morning there were many more incidents with the power steering than initially estimated.

Houlahan said the last generation of New Flyer trolley buses had an analogous problem that turned out to be quite serious.

"We would have the electronic brake kick out" after the trolleys passed a coupling. "That electrical change in the bus was causing a malfunction in the logic box that would kick out the electronic-dynamic brakes.

"That took us years to sort out and it was particularly scary because then you were only left with air brakes halfway through a stop, and the electronic brake was intended to do about 80 per cent of your braking," Houlahan said.

He said he hopes TransLink's optimism about a quick fix is well-founded.
"I'm hoping they can fix it in a day or two," he said. "Do I think that's likely or realistic based on my experience? No."

The problem buses were driven to the old Oakridge transit centre, which is still being used for maintenance and pre-delivery checks of newly arrived buses.


Trolley trouble

By Jeff Nagel Black Press
Feb 04 2007

All 39 of TransLink’s new electric trolley buses were pulled off the road Tuesday morning after drivers reported problems with their power steering.

The trolleys mainly serve Vancouver and Burnaby routes, but Coast Mountain Bus Co. is reallocating some diesel buses from other areas, meaning the trolley trouble may intensify the acute bus shortage that’s already causing delays and crowding for passengers across the region.

Officials said the glitch may be software-related and seemed to happen as a trolley’s power connection crosses insulator couplings at intersections, causing a momentary loss in power steering control.

“No one was hurt and there were no accidents,” said TransLink spokesperson Drew Snider, adding the trolleys are under warranty from supplier New Flyer Industries of Winnipeg.
Snider said it’s hoped the problem will be fixed quickly.

The new trolleys, which started to arrive last summer, were the leading edge of a $273 million order to buy 228 trolleys to replace the entire 20-year-old fleet.

It’s the second problem with New Flyer vehicles lately. In December, Coast Mountain decided new buses that had been arriving couldn’t carry bikes on their front racks after dark, because the racks block the headlights.


January 11, 2007

Perhaps They Should Have Tested More - NASA

I may be jumping the gun on this, but it appears a software update for the Mars Global Surveyor was buggy.

I'll try to watch this story and see if NASA comes to any different conclusions.

Software Glitch May Have Doomed Probe

Irene Klotz, Discovery News

Jan. 11, 2007 — NASA is investigating whether human error caused the loss of Mars Global Surveyor, a 10-year-old probe credited with finding signs of liquid water on the planet's surface.

The spacecraft fell silent in November after a problem with one of its solar array panels. Preliminary findings indicate software that was uploaded to Global Surveyor earlier in the year may have contained an error that set off a chain of events leading to the probe's demise.

Global Surveyor had already lasted four times longer than its design lifetime, but was about to embark on what might have been its most critical observations yet.

Scientists had hoped to fly the spacecraft over parts of Mars previously imaged to look for topographical changes. It was not just wishful thinking: Scientists had already found two locations showing signs of very recent water flows on the planet's surface.

It will be up to NASA's new spacecraft, the Mars Reconnaissance Orbiter, to pick up the surveys, as engineers have virtually no hope of recovering Global Surveyor.

"We still listen for it, but that's really the extent of it," NASA's Mars Exploration Program director Doug McCuistion told Discovery News.

The agency has set up a investigation board to try to figure out what happened to Global Surveyor. McCuistion said the software glitch is among the possible scenarios.

"Something may have occurred that we may never know," he added.

The board also will be looking into how the faulty software slipped through NASA's safety and quality control reviews. The program was intended to improve Global Surveyor's computer, but it had an error that may have caused the probe's solar array panel to jam.

The spacecraft then went into an automated emergency standby mode awaiting instructions, but engineers believe the battery, which was facing the sun, overheated and failed.

NASA used MRO as well as one of its rovers on the planet's surface to try to locate Global Surveyor, but the spacecraft could not be found.

Even with Global Surveyor's demise, Mars is still well-populated with robotic probes: two rovers have been scouring opposite sides of Mars' equator for signs of past water and three orbiters, including Europe's Mars Express, are circling the planet searching for water-bearing minerals and water-carved geologic formations.

NASA's next Mars mission is a lander named Phoenix that will touch down on the planet's north pole to study if the icy terrain could have — or possibly still does - support life. The Phoenix launch is scheduled for August.


April 14,2007 - an update...

It sure seems as if the bug fix made things worse.

"A software 'fix' sent up to NASA's Mars Global Surveyor spacecraft in June 2006 ultimately led to its failure five months later, a new preliminary report unveiled by the space agency has revealed.

The report has also said that the existing procedures used by the mission team were not thorough enough to catch the resulting problems, and that reductions in budgets and staff might have played some role in the loss of the mission."

"Incidentally, the incorrect June 2006 software upload was originally meant to fix a problem that arose in September 2005.

That is when two different engineers updated "in slightly different ways", two redundant control systems for the pointing of the high-gain antenna in 'error' mode, which led to a discrepancy in the computer's two memories, which the June 2006 upload was meant to rectify."


"Mission operators were not required to double-check the information they sent or test how it would affect the spacecraft, Perkins says. "Obviously, had these procedures been more rigorous … then perhaps this wouldn't have happened." "


"The review also said the spacecraft's onboard fault protection system failed to respond to the errors. Instead of protecting the spacecraft, the programmed response made it worse."


"We are making an end-to-end review of all our missions to be sure that we apply the lessons learned from Mars Global Surveyor to all our onging missions,” said Fuk Li, Mars Exploration Program manager at NASA’s Jet Propulsion Laboratory. "These lessons include the need for more thorough reviews of all non-routine changes to stored data before uploading as well as the need to evaluate contingency modes for overheating risks."