topgun17

 LOW COST VISUAL SYSTEMS

 presented to

 The Royal Aeronautical Society

 INTRODUCTION

The Paragon family of computer image generators has been described as the solution without compromise.  What value is a lower priced system if it fails to meet the rigid requirements of the user community?  The founders have an extensive personal background in the aerospace and simulation community.  Their personal experience in the field guarantees that equipment specifications are designed to satisfy the needs of the end user.

 APPLICATIONS

Rather than discuss the typical out-the-window visual simulation, it might be of more interest to discuss a few of the different applications our customers have found for the Paragon.

An interesting application of the Paragon system is for NASA's PAT (Pre Adaptive Trainer).  We all watched the astronauts perform their gymnastic feats of tumbling and spinning inside various spacecraft.  But most of us never realized that these activities cause serious illness in the astronauts.  Apparently, the eyes see the world tumbling about them.  But, due to the weightlessness of space, the inner ear does not sense the physical motion.  The brain therefore receives conflicting signals, recognizes that something is out of sync, and concludes that a probably cause is the ingestion of poisonous substance.  The body then attempts to rid itself of the poison.  This is similar to someone who over indulges in alcohol.  One of the first symptoms is dizziness followed by a short period of illness - that is, the body rids itself of the poison.

NASA has deduced through experimentation that adaptation to this subconscious mechanism can be trained; the eye and ear can experience a discontinuity without adverse effects.  But this training requires the astronaut be exposed to a similar environment.  We cannot experience weightlessness on earth for any practical period of time; however, various studies have shown that by restricting head and body movement, positive results can be achieved.

In the PAT, the subject is placed in a vacuum bean bag that conforms to the body providing a comfortable platform that inhibits (not prohibits) body motion.  The subject also wears a helmet attached to a force transducer that prohibits head motion.  This entire mechanism is then placed on a seat that rotates about the vertical axis inside a 6' radius dome.  A 2-channel Paragon illuminates the surface of the dome with an image of the Space Lab interior bay.  A combination of hand pressures on force plates and head pressures inside the helmet "propels" the subject within the lab.

We now have a scenario in which the eyes "see" movement, but the body does not feel movement. To compound this situation, the chair is commanded to rotate in one direction providing a slight stimulation to the inner ear, but the visual system is commanded to make the room appear to be spinning in the opposite direction, or even to tumble.  As you can imagine, it's quite a ride!  The Paragon displays a highly detailed scene at very fast update rates, but the really impressive feat is that the distortion correction algorithms are quite dramatic to allow fitting the image into such a small dome.

 

The US Army has experienced a number of unexplained incidents with one of its new attack helicopters.  In order to support the analysis of events, the Army employed an agency to retrofit the vehicles with inflight data recorders.  Now, after an incident, the Army can retrieve the data and examine several analog and discrete signals.  Unfortunately, there are so many variables, it has proven difficult to make a determination.  Now however, the Army simply provides the data set to Paragon, who reformats the data, and plays the vehicle flight path back on the Paragon computer, giving the Army the opportunity to analyze the incident visually, rather than with lists of numbers.

Another application is used by the U.S. Navy.  Device 2E6 consists of a pair of domed, full visual simulators to train fighter pilots in the basics of ACM (Air Combat Maneuvering).  Previously, the aircraft imagery projected on the dome surface was derived from a set of models viewed by a TV camera.  Not only were the number and types of threat aircraft limited, but the cost to maintain these systems was more than the cost for a one-time upgrade price to the Paragon.

The U. S. Naval Air Development Center has in one of its many research facilities, a manned centrifuge - the DFS (Dynamic Flight Simulator).  Pilots are subject to a number of flight experiments under various G loadings.  The tests were limiting because the visual system field of view was not only too small (30o x 40o) but the weight of the display was too heavy (700 lbs).  We not only provided a larger field of view (35o x 130o) and more scene content (2500 polygons at 60hz vs 1000 at 25hz) but we also reduced the weight to approximately 300 lbs total for all three channels.

 COMPETITIVE EQUIPMENT

A number of organizations have or are about to present exciting new systems for realtime simulation.  Several of these, like the Paragon, are priced several orders of magnitude less than the conventional systems.  But we at Paragon are proud that we have made no system or performance compromises to support the price reduction.

We still provide, for example:

 

     10000 polygons
     60hz update rates
     1000 line resolution
     rapid database generation
     32 floating point accuracy
    multiple 3-D moving models
     textured horizontal/vertical surfaces

 PARAGON

 Solution Without Compromise