Static & Crosstalk
Dr. E. Thomas Chesworth
Robots!
Some years ago I was called out to Heath, Ohio to solve the problem of a welding robot that lost its mind as soon as it started welding. This wasn't hard to believe because it also trashed nearly every computer in the building. The problems were easily solved with a ferrite here, a capacitor there, and rewiring so that crosstalk and unwanted ground paths disappeared and power line filters took care of them. It wasn't quiet but it was self-compatible and no noisier than the factory environment in which it lived.
This was one of the early industrial robots. It was on a machine base, bolted to the floor and meant for use in a factory. The electrical engineers responsible for the design were competent fellows, but they had never before run into EMI on that or any other scale. In those days and still, as far as I know, a robot was a machine with computer control and an articulated arm. The problem was the microprocessor, the wiring harness and the spark transmitter (welding head). The designers caught on quickly and were fast learners so I don't think the company built any more EMC catastrophes.
All robots have brains (microprocessors) sensitive to pulse and broad band interference at some level and robots that walk around have two special EMI problems. First, they have an undefined environment in which to operate. They may be in the near field of a search radar one minute and next to an arc welder the next minute. Second, they have sensors on the ends of their articulated arms which must be connected to the microprocessor, and they have a nervous system that extends all over the place.
Robots that have tracks or wheels are less likely to have sensors far from their main body. Because they are a robot they must have at least one arm but they don't have legs. Any robot that walks must have sensors on its legs or its performance is severly limited because it can't adjust its steps to match the terrain.
Two legs are bad news because it takes a lot of brain power just to keep your balance. We do okay because we developed from a four-legged animal and our ancestors decided they needed to carry stuff, so they turned two of the legs into arms. The next least effective walking strategy is to have four legs. You're fairly stable because you can have three legs on the ground at once (which is stable even on a rough surface so balance is easier) but you have to carry everything in your mouth, a nasty business if the stuff tastes bad.
I expect that in the future most robots who move around will either crawl (wheels or tracks) or have eight legs (actually six legs and two arms). For those of us who abhor spiders it won't be very pleasant. Who wants a spider the size of a Great Dane bustling around the house or our motel room dusting and making the bed? We may not mind them crawling all over the landfill sorting and arranging the garbage or bustling around the vineyard grooming the canopy, removing the insect pests and picking the grapes, but who wants to get personal with them?
For that reason alone human-looking robots will be used in the future in blue collar service jobs or as maids and servants in our houses and as clerks at the local big box stores. Our homes, offices and vehicles are designed for us so a robot who uses them should be configured like us in order to fit into the environment.