FischerTechnik clock in action скачать в хорошем качестве

FischerTechnik clock in action

FischerTechnik clock using a Hobby 1, Hobby 2 and a Computing box from 1987. Controlled by an Arduino and an Adafruit GPS module. For more information, see https://hackaday.io/project/7679. The clock has two motors: The adjustment motor in the middle (with the big worm gear) to turn the mechanism fast and with low accuracy, to adjust the clock. The minute motor on the left, which turns the vertical axis half of a rotation per minute to move the minute-hand to the next or previous minute position. The rest of the mechanics of the clock is the usual 12 to 1 reduction between hour hand and minute hands, but there is a differential gear between the clock mechanism and the minute-motor. When the adjustment motor is stopped, it locks the differential so that the minute-motor driving force is reversed and transferred to the clock. When the minute-motor is stopped, and the adjustment motor turns, the input gear of the clock turns at double the speed of the big wide gear that forms the differential. The differential makes it unnecessary to have any kind of friction coupling to adjust the time. The clock mechanism has three switches to help the software: The top-of-the-hour switch is on the back of the mechanism; it goes from "open" to "closed" when the minute-hand goes from minute 59 to minute 0 (the place where it opens is not important; the software ignores that. It would be an improvement to make a change so that the switch opens when the minute-hand is pointing to the 6, so that the software can use the switch to determine if it's more efficient to go forward or backwards when it starts adjusting). The noon/midnight switch is "closed" whenever the hour hand is near the 12 o'clock position and "open" when it's not. The minute-advance switch is on the left to detect whether the minute-advance motor has finished a half rotation to advance or reverse the minute hand. The software is basically a servo mechanism that compares the clock time to the actual time. It uses a GPS module to get the current time, and it uses the switches on the clock to keep track of what the clock is showing. If the clock is less than (I think) an hour off from actual time, the software activates the minute-advance motor to adjust it. If it's further away, it uses the adjustment motor to go to the nearest hour, and then it uses the minute motor to go forward or back to make the minute hand move to exact spot where it needs to be. This way, it's possible to turn the power to the mechanism off for any amount of time, and as soon as you turn the power back on, the clock will move to the current time as efficiently as possible. The video starts when the power has just been turned on. At that time, the software has no idea what the current time is or what the position of the clock is, so it turns the adjustment motor forwards or backwards (depending on the switches) to make it go to 12 o'clock. In this case it turned the hands backwards so it overshoots the 12 o'clock position a little and then corrects itself. At that point, the clock time is known, but it takes a little longer to lock on to the GPS signal so the clock sits still for a while. As soon as it gets a time from the GPS module, it starts adjusting the mechanism to show the actual time. Once that's done, the adjustment motor doesn't run anymore as long as the power stays plugged in. Every minute, the minute-adjust motor rotates the vertical axis on the left by 180 degrees (helped by the switch to determine where to stop) which advances the minute hand by one minute. The video shows it doing this one minute after it has reached it's initial actual time position. The software is hard-coded for my time zone but it can easily be modified to have adjustable time zones. Also, daylight savings time is a matter of adjusting the time zone offset by an hour, twice a year. The rest of the software will automatically adjust the clock when necessary; it doesn't matter if the time goes forwards by a minute, or changes by an hour (for daylight savings time), the software moves the clock to where it needs to be whenever the actual time changes.