Friday, December 14, 2012

A Christmas Moment for Great Science


The following is a fictitious tale that is based in part on a true story.

Of the twenty students in his class, only nineteen have registered to go on a field trip overseas during the upcoming Christmas season. Jeremiah is not going and the teacher knows why. He knows that something serious is about to happen to the town of Rallyville where Jeremiah lives with his parents. A one industry town that is ten miles away from the big city where the school is located, the town has been doing well for half a century but things are about to turn nasty for the people there. It is that the big factory will shut down early in the new year, and so will the shops that feed it with components, and the service industries that sprang around them including the bank branches, the insurance offices, the big stores and a few of the government offices – maybe even the elementary school and the church. Two thousand families representing eight thousand people in total will have the rug pulled from under them and nowhere else to stand; nowhere to go.

Rallyville was started by the grandfather of Jeremiah who was an electrical engineer. He opened the factory in the middle of nowhere and saw the place grow year after year as he kept expanding the factory and kept hiring people from out of town who then chose to settle in the town. The factory makes control panels used in the transmission of electricity to residential subdivisions and to industrial clusters that use electricity heavily. But there came a time when a holding company bought the factory from the grandfather and signed a contract with the son who is Jeremiah's father, to supply it with the relays, an important component of the control panel. Originally, the big factory was itself making the relays but the grandfather split the relay auxiliary from it and gave it to his son before himself splitting with the money they paid him, never to return to the town he founded.

Not known to be as ambitious as the grandfather, Jeremiah's father still managed to do well over the years, running the plant he inherited and never contemplating to upgrade the production line that kept producing the same old relays. In fact, he is fond of reminding anyone who would talk to him about the history of the town that his father had originally called the place Relayville in honor of the relays he used to make before expanding the operation to produce the entire control panel. The old man then changed the name of the place to Rallyville in honor of the people who rallied to it and put roots in it. Sadly, however, it is the lack of ambition on the part of the father that is the major factor at the root of the troubles that the town is now facing. It is that the holding company has decided to close the big factory because the competition is making modern control panels based entirely on solid state technology, something to which Jeremiah's father refused to switch when so advised.

The man has always insisted that there should be a way to continue making the control panels using the electromechanical relays that his plant is producing. Yes, the solid state technology is superior in some ways but his relays are superior in many other ways. If only the price of the precious metals had not skyrocket as it did, the customers that buy the control panels would still prefer the mechanical relays over the solid state relays. The trouble is that the contact points of the mechanical ones are made with silver, a precious metal whose price has gone up in tandem with the other precious metals. This made it more economical to use the solid states, something that more and more customers choose to do even though such relays cannot handle a heavy load of electricity as robustly as the electromechanical ones.

As to Jeremiah who will be going to college next year, he inherited the ambition of his grandfather, and has been raking his brains trying to find a solution to the town's problem. He knows that it all hinges on finding a way to keep making the control panels with mechanical relays that his father produces. But the price will have to come down to a level that can compete with the solid states. How to do that when it is obvious that the price of the precious metals will not go anywhere near the old levels again? Yes, the boy knows a great deal about electrical engineering because it has been the subject he liked the most during the high school years, and he plans to study it in college. But even he and his teacher, who is himself a specialist in the subject, have not found a workable solution.

The teacher who is responsible for this class and for two other classes gave up thinking about the subject, diverting his mental energies to organizing for the field trip. But he gave a final advice to Jeremiah before cutting loose from the project. As it happens, the teacher who is in a way a scientist has a brother who is a priest. The two have argued endlessly about the compatibility or lack thereof between science and religion. Unable to find a scientific solution to the problem, the teacher discussed the upcoming plight of the town folks with his brother who advised him to pray to God. And the teacher has dutifully transmitted the message to his student.

Jeremiah took the message to heart and went with it one step further. Instead of praying with words alone, he decided to pray with deeds. He thought of producing something he never produced before, something that will be harder to make than any project he made previously. He thought of a display for the church of the town where the parishioners will be able to push on a variety of buttons so as to light up the Christmas greeting of their choice. And he hoped that God will inspire him with an idea that will help save the town.

With faith in his heart and nothing more, Jeremiah bought the parts and components he needed for the project, and put it all together. But when he tried to make the thing work, he got gibberish instead of the clear messages he expected. Unable to determine why the gizmo is not working, he takes it to his teacher and asks for help. Of course, says the teacher, you have push buttons that are not buffered by debounce switches. What's that? asks the student. And the teacher explains that even though they are not seen by the naked eye, sparks (called bounces) are created by the push buttons. An ordinary light will not be affected by the bounces but when it comes to a digital circuit like this, every spark is taken as a new command to which the circuit responds, hence the gibberish that is displayed. The way to solve this problem is to design a buffer called debounce switch, and place it between the push button and the input of the circuit. What the switch will do is respond to the first spark then block all subsequent ones. And the intended message will be displayed with clarity.

Jeremiah takes the gizmo home, studies how to make a debounce switch, makes one, tries it and finds that it works. He makes a few more – one for each push button and mounts them all. He puts the finishing touches to the gizmo and takes it to the parish priest who likes it very much and promises that “Jesus will reward you for that.” Walking home, which is not far away from the church, a light suddenly shines bright inside Jeremiah's head. He exclaims: That's it! That's the solution! I found it, I found it! He runs home, grabs a pencil, a pad and a calculator. He does a few calculations and designs a contraption that will make it possible for his father to produce mechanical relays without the costly silver contacts, yet the contraption will transmit heavy loads of electricity as sturdily as before, and better than the solid states.

The idea is to make the contacts of the relay in copper which is something like a hundred and sixty times cheaper than silver. The problem with this idea, however, is that the sparks – which are created at the moment that the relay is activated – tend to melt the copper and weld the contact points, something that silver does not do as badly. The welding of the contact points will cause not only a malfunction in the system but can set it on fire thus create a far more dangerous situation.

But thanks to the idea of the debounce switch that has solved the problem of the push button, Jeremiah has thought of a way to adapt the principle to the problem of the relay contacts. What he will do is delay the load current a few microseconds by causing it to pass through a coil. This will be enough time for the relay contacts to go into the close position unburdened by the load that would have created the spark. Once closed, the current will then pass through the contacts without sparking and without welding.

Jeremiah builds a prototype of his invention and shows it to his father who takes it to the brass at the holding company that owns the factory that makes the control panels. The board of directors likes the idea and decides to keep the factory open. The town is saved, the people will have the best Christmas ever, and Jeremiah calls his teacher to say he will go on that field trip after all.

What did it? Was it Jeremiah's prayer or his scientific acumen? Let the teacher and his brother debate it.

NOTE: Unless something happens that will require an immediate response, I'll be on vacation till the New Year. Merry Christmas to all and a happy New Year. So long for now.