Using Advanced Sensors with VEX — Feel the Heat By Daniel Ramirez Discuss this article in the SERVO Magazine forums at http://forum.servomagazine.com.
Remember the movie comedy “The Nutty Professor” — a Dr. Jekyll and Mr. Hyde comedy spoof starring Jerry Lewis and Stella Stevens that came out in the late ‘50s (see Figure 1)? Scenes from the movie showed beakers full of colorful mixtures bubbling up in Bunsen burners, and spinning centrifuges all working together. Just think how great it would have been for the nutty professor if he had the advantage of automatic timer controls.
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id you know that VEX Robotics kits could be used in chemistry or biology labs? With the timers, digital I/O, and analog I/O, we can control almost any kind of experiment that requires mixing at specific time intervals, temperature monitoring, or even measuring light levels. Using VEX components, we can make useful lab equipment such as motorized paddles to stir liquids or timers to control chemical processes. Instead of having to constantly watch an experiment, the VEX microcontroller can monitor it and record the data for you. Think of how much time you would save, so that you could move on to other experiments and learn so much more. In previous articles, we’ve talked about how to use the microcontroller to track the sun using astronomical equations. Now, it’s time to introduce the VEX microcontroller to the chemistry, physics, or even the biology lab.
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FIGURE 1. A still from the movie comedy "The Nutty Professor" — a Dr. Jekyll and Mr. Hyde spoof starring Jerry Lewis and Stella Stevens that came out in the late ‘50s.
The VEX microcontroller provides the timers and electronic control needed for your experiments. It rivals older electronic controllers that are far more costly. Individual VEX microcontrollers can be purchased used on eBay at a lower cost. A VEX microcontroller has the following features that make it ideal for use in the lab: • Built-in timers that can measure durations in microseconds to days. • Reacts very quickly to real time events triggering interrupts, using its internal timers. • Responds by using its PWM (pulse width modulation) outputs to control motors, servos, relays, or solenoids. • Can switch electronic devices connected to it on or off, depending on events or sensor readings using
