How would you design the controls for a VCR (Video Cassette Recorder)?
It was said this is a popular interview question in many Tech companies like Microsoft, Google, etc. In fact, the complexity of setting the right time to record TV programs is a real problem that VCR manufacturers are keen to solve for the past 2 decades. There are numerous solutions designed throughout the years, including LED or LCD panels on the VCR, on-screen displays,
G-Code, VideoPlus+ and ShowView etc. Yet still correctly recording a specific program was somewhat complex operation for many people and none of the solutions really improve the situation a lot.
Below is the model answer suggested from the book "How Would You Move Mount Fuji?" by William Poundstone:
For the sake of argument, let's assume that consumer studies identify a market niche willing to pay for an easy-to-use VCR. It would also be helpful to know whether these potential customers really use all the features that most VCRs provide. How often do people program to record more than a week ahead? More than twenty-four hours ahead? Dropping some features could lead to an easier interface. As a rough sketch, here's how a plausible "easy" interface might work: The VCR box has only five buttons (play, pause, fast-forward, rewind, and eject). These are really just backups so that you can play tapes should the remote control fall behind the couch. The VCR box has no display (saving money). All the programming is done with the remote and on-screen menus. The remote has one button and one "joystick." The joystick is like those found on some monitors or on the keyboard in some laptops. It is hardly more than a button itself. You can move it in all directions in order to control an on-screen cursor. The button is for selecting. In essence, the remote is a mouse that you hold in your hand.
To program the VCR, you pick up the remote and touch either the joystick or the button. This "wakes up" the VCR (if it's off) and superimposes a menu/wizard/control panel on the TV screen. This interface lets you play tapes, record a program, and set the time (if for some reason it can't be synchronized automatically). The VCR downloads a graphical TV schedule and lets you simply point and click on the shows you want to record. Since the selling point for all this is the two-button simplicity, a great deal of attention should go to the look and feel of the remote control. It should not look like other remotes. If the market is young people, maybe it should look "cool," sort of like an iMac. If the market is retirees, make sure the joystick and buttons are easy to control for people.
In another way to figure the programing problem of a VCR, the basic question should be asked is: what is the easiest way for a person to do the recording correctly? A simple answer is to find a capable person who is always available to do it for him, right?
Most of the time, when people are not at their home and in somewhere with friends or at work, they may come across that there are something interesting will be shown on TV today or in future suddenly from friends, newspaper, or co-workers. So the impulses to record some TV programs are usually stipulated when they are not at home. For certain, the most convenient way to do the recording is to call back home for someone to start the recording or program the VCR for them. Or the other way is to call some friends they know that he/she will be at home and is willing to do it for them, although in most of the case, this is even harder to find that someone.
Deduced from the above, the most ease-to-use VCR control should be something that people could tell it to do what they want especially when they are outside in somewhere not near to the VCR. In reality, although the infrastructures are all here, such as phone line, low cost microprocessors, voice recognition, etc. However, voice recognition is never performed very well even not considering the cost of developing the system.
Then, how about the second best thing that a mobile phone could do in sending instructions. That is the text function (the SMS - short message system). The VCR control could be designed with a mobile phone SMS module built-in to receive text messages. Simple instructions could be set like this:
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| channel 8, record 19:00, stop 20:32, today | |
Or for even simpler instruction, it could be like this:
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| ch 8, rec 19.00, stop 20.32, mar 30 |
The VCR control could read the sentence and "understand" it and execute the commands accordingly. Then the VCR remote control and the box will remain just only five buttons (play, pause,fast-forward, rewind, and eject).
Or it could be in the other way around, the VCR itself could be connected to the land line with text function or with a SMS card module inside.
This could be the simplest way to control something need to be set the schedule time. The idea was first come from trying to control the Air Conditioner to start up cooling 15 to 30 minutes before family members arriving home. But it seems this could also be used in controlling VCR.
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