There seems to be a rush to judgment to find the flaws that caused the I-35W bridge to collapse in Minneapolis. The new theory—faulty steel gusset plates—strikes me as grasping at straws. Why after 40 years would faulty plates suddenly result in a catastrophic failure? Why has this never been raised before as a potential flaw in this type of bridge? As MIT metallurgist Ken Russell pointed out here recently, steel is made in huge batches, and its chemistry is carefully tested. Suddenly we discovered that this ancient batch was a bad one? Or that the designer used a wrong gauge or grade of steel?
It probably will take months for a meaningful analysis of the bridge failure to emerge. Undoubtedly, the investigators will find a frightening list of contributors to the collapse, starting with the corroded steel roller bearings already reported as deficient in 1990.
A new compression molding compound material combines the light weight, strength, and rigidity of carbon fibers with the flexibility and lower cost of glass materials in a composite compatible with automotive production.
Plastic bearings are real and millions of them are in use doing heavy-duty jobs we used to think only metals could do. Some of Germany-based igus's bearings are traveling around the world as functional parts in a car to demonstrate what they can do.
Baxter showed off his 2.0-derived moves at ATX West this year. The big red guy still looks pretty much the same, but has some new abilities, mostly due to software. The research robot version is now being used in corporate R&D departments as a design platform.
End-production using 3D printing, including objects made of multiple materials in one pass, is getting closer to reality as we saw on the exhibit floor at the recent Pacific Design & Manufacturing Show.