MEAM.Design - MEAM 410/510 - L1 (Stalker) - Part D: Stalker

Lab 1, Part D: Stalker

Design and build a device to track an infrared beacon over a 180-degree arc at a distance between 50 and 90 centimeters.

The Beacon

Mounted horizontally at a height of 5.0-centimeters above the ground, the beacon will consist of a single LTE-4206 LED driven by a circuit identical to the one you built for B.1.1 (though without the dimming potentiometer). The beacon will remain oriented toward your stalker at all times.

Your Stalker

Your stalker must remain within a 20-centimeter diameter cylinder at all times (there is no height restriction). Power to drive your stalker can come from either a bench-top power supply or self-supplied batteries.


You can choose to drive your stalker with either the right-angle or straight DC motor, which will be available from the TAs (along with the lasers) starting on Friday, September 9th.

Lasers (Pew Pew!)

You must integrate a red dot laser diode module (30mA@3V maximum, 650nm output) into your stalker in such a way that it will point toward the LED beacon. A +3V regulator (MCP1702-3002E, datasheet found here) and proper current limiting resistor must be used in conjunction with the laser diode module. For safety reasons, you should use the lowest possible current that provides a clearly visible dot at a range of one meter (to make this easily adjustable, use a discrete resistor in series with a dimming potentiometer in the same manner as you did in B.1.1).


With the IR beacon turned off, you will place your stalker on the testing platform. After you enable your stalker, the beacon will be moved to a random location and turned on. Your stalker should then stabilize the laser dot on the beacon. Once stabilized, we will measure the absolute error (horizontal distance, in millimeters between the laser dot and the center of the beacon) and peak-to-peak oscillation amplitude (also in millimeters). The beacon will then be turned off, moved to a new location, and turned back on. This process will be repeated for four total trials. Your overall score will be computed as the absolute errors plus the oscillation amplitudes plus 10 for each time that you had to touch your stalker. Check the calendar for TA availability before the deadline.

Documentation and Cleanup

To conclude this project, write a concise description of your system and include any sketches or images to accurately explain the various aspects of your design. Include a discussion on what went well and what you would improve if you were to begin again. Bring your writeup, ALONG WITH YOUR LASER DIODE to class on Monday.