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Demonsong
Aug 5th, '03, 08:56 AM
How would you build a Motion Tracker?

You know like in the Aliens Movie, that the Marines were using. Would it be active like radar, or passive? Would you use some form of N-Ray Vision to since motion through walls, it would probaly be 360 degee. Yuck, this could get overly complicated and expensive quickly.

Killer Shrike
Aug 5th, '03, 09:06 AM
Originally posted by Demonsong
How would you build a Motion Tracker?

You know like in the Aliens Movie, that the Marines were using. Would it be active like radar, or passive? Would you use some form of N-Ray Vision to since motion through walls, it would probaly be 360 degee. Yuck, this could get overly complicated and expensive quickly. Spatial Awareness, OAF.

Lord Liaden
Aug 5th, '03, 09:23 AM
Originally posted by Killer Shrike
Spatial Awareness, OAF.

My impression of Spatial Awareness is that since it's based on Detect Physical Objects, it wouldn't work through walls or other solid barriers as did the detectors in "Aliens." That's open to interpretation, of course. :)

I think I would go with Detect Motion, Sense, Range, OAF Detector. AP 10, RP 5.

I'm not sure whether the motion detector from "Aliens" would be an Active or Passive Detect, though. Picking up an object's motion would seem to be passive (the object has to be doing something to be detected), but the detector display seemed to indicate that some type of pulse was being sent out

Killer Shrike
Aug 5th, '03, 09:27 AM
Spatial Awareness is NRay

http://www.herogames.com/forums/showthread.php?s=&threadid=4845&highlight=Spatial+Awareness

Killer Shrike
Aug 5th, '03, 09:32 AM
Also, a useful tidbit thats not necessarily relevant here, but if you dont piggy back SA on a ranged sense using the Simulated Sense rule, you do need to apply Range to it:

http://www.herogames.com/forums/showthread.php?s=&threadid=3229&highlight=Spatial+Awareness

In this case, I would say that the detector Simulates both Sight (user looks at the scanner) and Radio (the scanning itself) for IIRC a -1/4 lim

Demonsong
Aug 5th, '03, 10:38 AM
That is really different that what I thought. Thanks

Demonsong
Aug 5th, '03, 10:40 AM
Ok but then you would but a -½ (?) disadvantage on it, Only Moving Items?

Killer Shrike
Aug 5th, '03, 11:00 AM
Originally posted by Demonsong
Ok but then you would but a -½ (?) disadvantage on it, Only Moving Items? Maybe even a -1 in this case.

Toadmaster
Aug 5th, '03, 11:08 AM
Originally posted by Lord Liaden
My impression of Spatial Awareness is that since it's based on Detect Physical Objects, it wouldn't work through walls or other solid barriers as did the detectors in "Aliens." That's open to interpretation, of course. :)

I think I would go with Detect Motion, Sense, Range, OAF Detector. AP 10, RP 5.

I'm not sure whether the motion detector from "Aliens" would be an Active or Passive Detect, though. Picking up an object's motion would seem to be passive (the object has to be doing something to be detected), but the detector display seemed to indicate that some type of pulse was being sent out

This fits my view of the motion detector and eliminates the need to lims to only detect moving targets. From what I remember the motion detectors in Alien worked by sensing air movements (I remember some discussion of the fuctioning of the motion trackers in Aliens) so I would guess they were passive, although sonar or radar would probably be reasonable ways to build a similar device.

Demonsong
Aug 5th, '03, 11:35 AM
But that form is not going to see throught wall. Correct?

Space Cadet
Aug 5th, '03, 11:29 PM
From descriptions of the Aliens motion tracker that I've
read or heard of, the device uses changes in air density and
movement as well as radar to detect and track enemies that
aren't immediately visible to the user.

Space Cadet :cool:

Toadmaster
Aug 6th, '03, 01:54 PM
I forgot I had this but Leading Edge did an Aliens RPG, it has a nice equipment section which appears to have been well researched. Here's what they said about the motion tracker:

A sonar unit combined with passive air density sensors, the motion tracker is used to provide Colonial Marines with information about unseen enemies.

snip

A motion tracker will indicate the position, size and speed of any object within 180 feet. The size of object the motion tracker is scanning for is determined by the user, down to a minimum diameter of about 6". The frequency and settings must be adjusted repeatedly to filter interferance, and operating the motion trackerin cluttered terrain is difficult without a good deal of skill and experience.

snip

The motion tracker will not work in vacuum. The motion tracker can register movement on the far side of a solid obstacle, but the air flow between the two locations must be unblocked, and the operator's task is made more difficult; for each corner or intervening obstacle.

I realize you are just making an Aliens like motion tracker but hope this helps.

Talon
Aug 6th, '03, 02:08 PM
Originally posted by Space Cadet
From descriptions of the Aliens motion tracker that I've read or heard of, the device uses changes in air density and movement as well as radar to detect and track enemies that aren't immediately visible to the user.

"Micro changes in air density my ass!"

:)

Killer Shrike
Aug 6th, '03, 10:08 PM
Originally posted by Geoff Speare
"Micro changes in air density my ass!"

:) How do I get out of this chickenshit outfit?