The Laser Display Project
2.737 Designing Smart Machines - 1996

The laser display was developed in the Spring of 97 as a completion hands-on project for the Designing Smart Machines class, taught by Professor Trumper and by Pradeep, TA.

The setup consits of two high speed scanners by General Scanning onto which two mirrors are mounted. The scanners are driven by power coming from a PA45 amplifier.

The relative position between mirrors is so that a laser beam (coming from an ordinary laser pointer) bounces on the two reflective surfaces and reaches the ceiling.

The motion of one of the mirrors correspond to an "X" displacement on an imaginary axis on the ceiling. The motion of the other one creates a "Y" displacement.

An inverse kinematic scheme was implemented on a 486 computer. This scheme "translates" desired X-Y displacements on the ceiling into desired mirror positions, to be commanded to the scanners.

The control scheme is based on an analog double lead compnsator for each scanner. The rising time obtained was about 4msec.



Check this 20 sec MPEG movie with one actual display in motion.


A REAL TIME FOURRIER TRANSFORM

In this diplay, a fourrier transform of a signal coming from an FM radio is plotted on the ceiling. The sound is captured by an AD converter and then real time processed by the computer. Finally, the trace is displayed. See picture above, on the left. Group: Razman Zambri, Larry Barrett and Ryan Boas.

ISOMETRIC ROTATING OBJECTS

In this display, isometric projections of 3-D objects such as pyramids and cubes were plotted. The objects can rotate in any direction and also shrink or increase in size. A movie capture of the actual display, portraying the objects and "MIT" rotating in various directions is available. MPEG (244 Kbytes). Group: Bernardo Aumond, Steven Villareal and Karl Iagnema.




This page was written by
Bernardo Aumond and Razman Zambri
 July 21, 1997