William Kienzle: Shadow of Death

The group moved along the production line.

“These are the cord wood cutters,” Culpepper pointed. “Now the glass’s in rectangular shape. It’ll be cut one more time into the desired windshield size further on down the line. See? Some of the glass has already been broken or damaged. Well, these guys,” he indicated workers wearing heavy gloves and positioned on either side of the conveyor, “pull off all the spoiled glass and just let it drop down there, where another conveyor going in the opposite direction takes the glass back to the beginning where the cullet becomes part of the batch all over again.”

The glass that survived all this cutting and jostling was carefully removed from the conveyor system by workmen, again heavily gloved, who stacked the glass in wooden brackets. The brackets were then manually loaded on dollies and transported to the next stage of the operation.

“And here,” continued Culpepper, as the group reached a rather congested area, “is where the glass is shaped into the windshield.” Sensing Hoffman’s interest, Culpepper let the machines do the talking for a few minutes.

Ingenious, thought Hoffman. Untouched by human hand. A robot with four arms extending from its control box, the arms bent downward where suction cups replaced hands . . . hands that picked up the bracket glass, a single pane at a time, then swung it to another machine. The robot then positioned the glass carefully and precisely on the table of another robot. The well-oiled “finger” of the second robot, armed with a glass cutter, traced the shape of a windshield on the glass. The outside rim fell off, and a perfect windshield would be delivered to the next worker in the chain.

Yes, Hoffman had to agree, in time this entire operation might well be totally automated.

“Like a mother picking up a baby,” commented Culpepper, having allowed time for Hoffman to become mesmerized by the robots. “Its sensors establish the limits of how far it moves the glass, and then it counts the pulses before laying the sucker down right on the exact spot. Amazing, ain’t it?”

The two men were by no means alone in the fascination with the robots. The eyes of the entire entourage were riveted to the process.

Something was wrong. Culpepper sensed it rather than reasoned it. His right arm shot out, catching Hoffman on the shoulder, knocking him to the floor.

Instead of delivering the glass in its usual herky-jerky fashion, the robot’s arms swung in a smooth, forceful, fast arc, passing through the space just vacated by Hoffman, and stopping only when it smashed into a nearby pillar.

Culpepper bent to the visibly shaken Hoffman and helped him to his feet.

The robots ground to a halt. Someone had cut the power. But Culpepper seemed the only one interested in Frank Hoffman. The technicians and engineers were absorbed in their machine, trying to figure out what had caused a fail-safe device to fail . . . and only incidentally, come within a hair’s-breadth of killing a man.

“What we’ve got is a bad case of axis runaway,” stated a tall, laconic Bill Kelly, the glass plant’s chief engineer.

“Could you explain that a little more fully?” asked one of the two black Detroit police officers who had responded to the call.

The officers, Kelly, Culpepper, and Hoffman stood near a work table in the plant manager’s office.

Kelly nodded. “The robot is programmed to make suction contact with the glass, raise it from the bracket, and move it to the cutting machine, counting the pulses on the way. At the exact count of the exact number of pulses, it lowers the glass to the cutter. Instead of moving on its axis to the count of pulses, it lost its programming entirely.

“In layman’s language, all hell broke loose.”

The officer suppressed a smile. “And can you tell us how this could happen?”

Kelly nodded again. “Y’see, the type of material used for this silicone chip is a metal oxide semiconductor. We know it as just MOS. And, y’see, if an external, static-type current is applied over the MOS, it’ll fail—in a completely unpredictable way.” He looked from one officer to the other to make certain each understood.

“So,” the officer said, as he finished writing on his notepad, “this ‘external, static-type current’ could come about accidentally? Or would someone have to bring it about intentionally?”

“No; it could happen accidentally.”

“Could you think of any way in which this ‘axis runaway’ might be deliberately caused?”

Again Kelly nodded. “Sure. Somebody could enter a sequence in the computer programming the robot’s probe—or arm—to run away and break its sequence.”

“I see. But if someone were to enter such a sequence in the computer, an expert like yourself would be able to find it?”

“No,” Kelly scratched his chin, “. . . not necessarily. Anybody who could program a switched sequence like that could also program the computer to erase the sequence from its memory.”

“Just like that?”

“Just like that. A couple of numbers would do it.”

“I’ll have to bow to your expertise,” said the officer, “and admit that it’s possible for someone to program this robot runaway and also to erase the memory of this programming from the computer. But if Mr. Hoffman were the targeted victim, how would the programmer know the precise moment when Mr. Hoffman would be standing in the exact spot where he could be hit?”

“Now,” Kelly replied, “I’d have to guess. But my guess would be that if someone—someone clever enough to reprogram a computer—were out to kill Mr. Hoffman, it could have been done anywhere along the line. A little shove into the furnace. A failure of the glass cutter. Any number of ‘accidents.’ With Mr. Hoffman standing in the path of the loading robot, with everyone’s eyes on the robot’s procedure, anyone easily could have slipped over to the computer controls and quickly reprogrammed it. It would require only a few seconds. Oh, yes; it could be done easily.”

The officer, seemingly satisfied, nodded. But he would later question the men who had been working in the area to see if any of them had noticed anything or anyone unusual in the vicinity of the control box.

For now, he turned to the plant manager. “Mr. Culpepper, what kind of security do you have in this plant?”

Culpepper looked embarrassed. “Well, none, really. There are no uniformed guards—or plain-clothes guards, for that matter. We try to keep our eyes open, but it’s almost impossible. The other day, I saw somebody wandering through, taking pictures, so I challenged him. Turned out he was on assignment by The Company and nobody had notified us. But, just about anybody can come through here, especially if he or she is wearing work clothes. Nobody wears identification tags. And the place is so big nobody knows everybody else.”

“So, if this thing had been caused by someone who reprogrammed the computer, that person might or might not be working here?”

“Right. Or, for that matter, if somebody did reprogram the computer, he or she could have been hired by someone not at all associated with The Company.”

Kelly leaned forward. “One thing puzzles me, Amos: How in hell did you ever guess that the probe was out of control? I mean, a split second later and we would have had a major league tragedy.”

“I’m not sure even now.” Culpepper, still shaken by the incident, shook his head. “The arms came up just a fraction too fast. And, when the probe missed its first pulse count . . . I . . . I just reacted.”

“A lucky reaction as far as Mr. Hoffman is concerned.” He turned to an obviously angry Hoffman. “Mr. Hoffman, who knew you were going to make this—uh—operating review today?”