New Placement Idea

[Riptide]

I've been toying with the idea of angling my outer two sensors of my trihead setup outward, or getting a 4th sensor in addition to the angling. After brainstorming with mrkookm and making some computer mockups I really think this could work and make a car damn near bullet proof against off axis shots.

Numbers are in feet, and darker color means more signal strength.

Current trihead vs trihead with outer two sensors angled 10 degrees out
http://i1128.photobucket.com/albums/m489/R1ptides/LI/laserinterceptor2.jpg

4 heads with outer two angled out 25 degrees
http://i1128.photobucket.com/albums/m489/R1ptides/LI/laserinterceptor5.jpg

Only testing will tell if it will work, hell communism looked great on paper and we all know how that turned out.

Thoughts?

[chriskohtc]

Is it really worth it?

From a lidar operator's perspective,

1) Is it hard to get a reading when shooting at extreme off-axis angles?

2) Cosine-error involved will result in diminished speed readings anyway

[Stealth Stalker]

I seriously considered the same thing, although I didn't computer model it like you did, lol. I had planned to move my rear sensors up and angle them out very slightly, and put a new LI on the rear. Specifically, I would have put them on the SVMs. Seems like a great idea to me, because off-axis coverage is the only thing I even remotely fear with an LI.

It'd take a LOT of testing to measure the differences, but I believe it would be worth it.

[SaltyinNJ]

http://autos.aol.com/cars-Acura-TL-2008/photos/

I actually did this today.


I had two original heads on top part of grill right under the hood. As far towards the HL as it can go. I put two more on the top part of both bottom grills. They naturally point outwards. I know this is usually a no no, but I figured I'd give it a try. Only testing will tell. Anyone wanna lend a hand?

EDIT: BTW, I left the original two where they were. I'm now running a LI Quad up front.

[CJR238]

http://autos.aol.com/cars-Acura-TL-2008/photos/

I actually did this today.


I had two original heads on top part of grill right under the hood. As far towards the HL as it can go. I put two more on the top part of both bottom grills. They naturally point outwards. I know this is usually a no no, but I figured I'd give it a try. Only testing will tell. Anyone wanna lend a hand?

I believe it works even with 2 heads on a small car. I did this with mine because of one of my head placements and it was JTG with all the guns tested. Will need to test more.

[SaltyinNJ]

http://autos.aol.com/cars-Acura-TL-2008/photos/

I actually did this today.


I had two original heads on top part of grill right under the hood. As far towards the HL as it can go. I put two more on the top part of both bottom grills. They naturally point outwards. I know this is usually a no no, but I figured I'd give it a try. Only testing will tell. Anyone wanna lend a hand?

I believe it works even with 2 heads on a small car. I did this with mine because of one of my head placements and it was JTG with all the guns tested. Will need to test more.

Let me know when you're going to test if ya dont mind.

[SaltyinNJ]

I'm free tomorrow if anyone has a gun and wants to test.

[mrkookm]

...........

[Riptide]

I seriously considered the same thing, although I didn't computer model it like you did, lol. I had planned to move my rear sensors up and angle them out very slightly, and put a new LI on the rear. Specifically, I would have put them on the SVMs. Seems like a great idea to me, because off-axis coverage is the only thing I even remotely fear with an LI.

It'd take a LOT of testing to measure the differences, but I believe it would be worth it.

I agree completely. If you got your placement right and have enough heads for the size of your car/truck/airplane/whatever straight on shots will never be a problem for the LI. I don't understand why people still test this way. Unless you have a bunch of people with blinders attending your meet, do everything off axis.




The placement of the sensors is key for many reasons. Keep in mind the sensors have to be installed in such as way so that the 'see' the lidar being shot. If it can't see the gun IR then naturally it will not fire. It can be HP's, dual or quad regs, its not about how many sensors or diodes we rocking on our cars its the placement that counts.
+100000000000000
noobies write this sh1t down and don't b1tch to Cliff when your botched install gets PT

[SaltyinNJ]

I'm free tomorrow if anyone has a gun and wants to test
I know you are excited, but please don't detract the thread. If you want to test you know 1 individual who you can reach to.

The placement of the sensors is key for many reasons. Keep in mind the sensors have to be installed in such as way so that the 'see' the lidar being shot. If it can't see the gun IR then naturally it will not fire. It can be HP's, dual or quad regs, its not about how many sensors or diodes we rocking on our cars its the placement that counts.

Detract the thread? I simply said that I just happened to do this type of setup and was wondering if anyone was available for testing. Its not that I'm excited, its that I have one day a week off so I was throwing it out there. Thought I was contributing but if you feel I'm "detracting" from the thread, well, I dont know what to say to that. I know that more heads doesn't necessarily mean I'm bulletproof. That's why I wanted to test to see if it would actually work. But thanks for the advice anyway. Always have an open ear to learn more no matter what I think I already know.

[g_jammer]

...... its the placement that counts

Bingo!

The following is only my opinion from tests I have conducted.

The difference between a properly installed counter measure vs. a improperly installed one is absolutely staggering.

A good install of 2 heads will easily deliver JTG performance in just about every scenario you will encounter on most vehicles, given that, as mrkookm said, the LI is able to see the beam. Making one wonder what is the point in littering the front of your vehicle with more transceivers if there won’t be any real gain.

And for the few very off axis shots where the attack angle becomes very acute as you get closer to the LIDAR threat, JTK time is ample.

Speaking of far off axis shots, consider a far off-axis shot even from just a couple hundred feet away becomes a obtuse angle, a properly installed LI won’t have any trouble seeing and defeating the threat. At greater distances, the angle is reduced even further and that much easier to see and defeat.

At a very short distance where a far off axis angle does become acute & hard to see the beam, the LEO would essentially be firing at you laterally, creating cosine errors, assuming the LIDAR would even be able to lock.

[SaltyinNJ]

...... its the placement that counts

Bingo!

The following is only my opinion from tests I have conducted.

The difference between a properly installed counter measure vs. a improperly installed one is absolutely staggering.

A good install of 2 heads will easily deliver JTG performance in just about every scenario you will encounter on most vehicles, given that, as mrkookm said, the LI is able to see the beam. Making one wonder what is the point in littering the front of your vehicle with more transceivers if there won’t be any real gain.

And for the few very off axis shots where the attack angle becomes very acute as you get closer to the LIDAR threat, JTK time is ample.

Speaking of far off axis shots, consider a far off-axis shot even from just a couple hundred feet away becomes a obtuse angle, a properly installed LI won’t have any trouble seeing and defeating the threat. At greater distances, the angle is reduced even further and that much easier to see and defeat.

At a very short distance where a far off axis angle does become acute & hard to see the beam, the LEO would essentially be firing at you laterally, creating cosine errors, assuming the LIDAR would even be able to lock.



With the way my vehicle is, the only place to mount without having to drill into the actual body of the car itself is to mount on the grill, as far out to the left and right as possible. While I believe this is the most practical way to mount two heads, unfortunately this setup prevents the LI's from "seeing" the outer part of my wraparound headlights. Therefore, I decided to see if adding two more heads at a slight outer angle would give me JTG performance. If it doesn't help, I can simply remove the heads as it is mounted with M3 tape at the moment. For some reason, I have a feeling this new setup will help. I can't really think of a reason why it wouldn't improve performance. I'm sure a two head setup on my car would beat most real world encounters, but that crazy off axis shot scares me.

[g_jammer]

With the way my vehicle is, the only place to mount without having to drill into the actual body of the car itself is to mount on the grill, as far out to the left and right as possible. While I believe this is the most practical way to mount two heads, unfortunately this setup prevents the LI's from "seeing" the outer part of my wraparound headlights. Therefore, I decided to see if adding two more heads at a slight outer angle would give me JTG performance. If it doesn't help, I can simply remove the heads as it is mounted with M3 tape at the moment. For some reason, I have a feeling this new setup will help. I can't really think of a reason why it wouldn't improve performance. I'm sure a two head setup on my car would beat most real world encounters, but that crazy off axis shot scares me.

There is zero harm in experimenting, as long as the end result provides the desired effect and reliably, using proven results as your guide.

One other thing to keep in mind as you experiment is about how the countermeasure actually see's the LIDAR beam, which you may or may not be aware of.

The transievers can't "see" in the ordinary sence, the open road in front of it and the incomming LIDAR beam. Instead, the infrared beam must directly shine into the transceiver when it hits your vehicle in order for the countermeasure to alert and respond, which means the transceiver will either be within the circumference of the beam hitting your car & it will respond, or it will be outside the circumference of the beam & it will not, regardless of angle of attack, or what angle the transceivers are facing.

From what you describe about your headlights and the LI not seeing the beam, it seems that it is very short range headlight shots, and not angle that you may be worried about.

However, as I said, there is nothing wrong with experimenting, testing, tweaking & retesting, that is a very fun and important part of owning a countermeasure.

Good Luck. :)

[ivirovets]

What about mounting heads on the roofline? I suggested this to Salty half jokingly the other day but I was seriously thinking about it. If a convenient mounting location could be located, wouldn't this protect from cresting-the-hill roofline shots? They couldn't be mounted inside because internal reflection in the glass could cause eye damage using LI's.

[SaltyinNJ]

1

[SaltyinNJ]

What about mounting heads on the roofline? I suggested this to Salty half jokingly the other day but I was seriously thinking about it. If a convenient mounting location could be located, wouldn't this protect from cresting-the-hill roofline shots? They couldn't be mounted inside because internal reflection in the glass could cause eye damage using LI's.

Now you're thinking like SS with these crazy but probably effective locations.

[ivirovets]

If I had the cash for an LI quad I'd buy one and try it.

[g_jammer]

...



Red looks like will prove years of PT free service, but have fun experimenting with blue :-)

What I can tell you however is my sedan is wider than yours in front, more chrome, and my headlights are larger, are slightly set back from the grill (harder to defend) and wrap around even more than yours. I have LI duals heads similarly placed as your RED, I do not get PT's, even off axis head light shots, if that makes you feel better. (Can't post a pic, I go thru a ton of LIDAR traps & countermeasures are illegal in IL, dont need any extra attention)

[SaltyinNJ]

...



Red looks like will prove years of PT free service, but have fun experimenting with blue :-)

What I can tell you however is my sedan is wider than yours in front, more chrome, and my headlights are larger, are slightly set back from the grill (harder to defend) and wrap around even more than yours. I have LI duals heads similarly placed as your RED, I do not get PT's, even off axis head light shots, if that makes you feel better. (Can't post a pic, I go thru a ton of LIDAR traps & countermeasures are illegal in IL, dont need any extra attention)

No worries. Maybe its just b/c its raddarob shooting. Dudes hand wouldn't flinch in an earthquake. Anyway, I took down pic for same reason and dont want to take notice away from OP.

[CJR238]

What about mounting heads on the roofline? I suggested this to Salty half jokingly the other day but I was seriously thinking about it. If a convenient mounting location could be located, wouldn't this protect from cresting-the-hill roofline shots? They couldn't be mounted inside because internal reflection in the glass could cause eye damage using LI's.

I will be testing this.

[radarrob]

i have 2 Li hp heads to conduct this test on roof when I'm not busy and have a day off.

[Riptide]

...... its the placement that counts

Bingo!

The following is only my opinion from tests I have conducted.

The difference between a properly installed counter measure vs. a improperly installed one is absolutely staggering.

A good install of 2 heads will easily deliver JTG performance in just about every scenario you will encounter on most vehicles, given that, as mrkookm said, the LI is able to see the beam. Making one wonder what is the point in littering the front of your vehicle with more transceivers if there won’t be any real gain.

I think the most gain is had by the additional receivers much more so than the added output. This is why something like the laser tamers appeals to me, double your receiving sensor coverage.

And for the few very off axis shots where the attack angle becomes very acute as you get closer to the LIDAR threat, JTK time is ample.

Speaking of far off axis shots, consider a far off-axis shot even from just a couple hundred feet away becomes a obtuse angle, a properly installed LI won’t have any trouble seeing and defeating the threat. At greater distances, the angle is reduced even further and that much easier to see and defeat.

At a very short distance where a far off axis angle does become acute & hard to see the beam, the LEO would essentially be firing at you laterally, creating cosine errors, assuming the LIDAR would even be able to lock.



Can you clarify what you mean by acute and obtuse? Its been a while since I took geometry but I remember acute meaning <90degrees and obtuse >90degrees. I don't see how its possible to have an angle greater than 90. See alpha in graphic:

http://copradar.com/preview/chapt2/f2d1d1.gif
Also I wouldn't bank on cosign saving you. At our last ECCTG meetup one of the shots had the shooter 60' off the road and everyone was getting PTs of ~150'
This results in an angle of 23.6 and a cosign of .916.
Say you were doing 60 in a 45, (60 * .916)= ~55
55 in a 35 - ~50







With the way my vehicle is, the only place to mount without having to drill into the actual body of the car itself is to mount on the grill, as far out to the left and right as possible. While I believe this is the most practical way to mount two heads, unfortunately this setup prevents the LI's from "seeing" the outer part of my wraparound headlights. Therefore, I decided to see if adding two more heads at a slight outer angle would give me JTG performance. If it doesn't help, I can simply remove the heads as it is mounted with M3 tape at the moment. For some reason, I have a feeling this new setup will help. I can't really think of a reason why it wouldn't improve performance. I'm sure a two head setup on my car would beat most real world encounters, but that crazy off axis shot scares me.

I think we need to stop installing and then testing. Go to a test meet, do multiple temporary installs using 3m tape, test them, then do a permanent install with what works best

There is zero harm in experimenting, as long as the end result provides the desired effect and reliably, using proven results as your guide.

One other thing to keep in mind as you experiment is about how the countermeasure actually see's the LIDAR beam, which you may or may not be aware of.

The transievers can't "see" in the ordinary sence, the open road in front of it and the incomming LIDAR beam. Instead, the infrared beam must directly shine into the transceiver when it hits your vehicle in order for the countermeasure to alert and respond, which means the transceiver will either be within the circumference of the beam hitting your car & it will respond, or it will be outside the circumference of the beam & it will not, regardless of angle of attack, or what angle the transceivers are facing.

I think theres a bit more to it than this. At 250' the lidar guns beam (most of them with 3mrad beam width) is 9 inches wide. If the jammer's sensor had to literally be within this cone (its more like a rectangle in reality) I would think it would be pretty easy to get PT on most dual setups. Reflections or scatter or something else have to be playing a part in this.

From what you describe about your headlights and the LI not seeing the beam, it seems that it is very short range headlight shots, and not angle that you may be worried about.

However, as I said, there is nothing wrong with experimenting, testing, tweaking & retesting, that is a very fun and important part of owning a countermeasure.

Good Luck. :)


What about mounting heads on the roofline? I suggested this to Salty half jokingly the other day but I was seriously thinking about it. If a convenient mounting location could be located, wouldn't this protect from cresting-the-hill roofline shots? They couldn't be mounted inside because internal reflection in the glass could cause eye damage using LI's.
Not sure about the eye damage, but I've done over the hill testing with a higher placement (not on the roof but on the top of my upper grille) and I didn't have any issues with roofline PTs.

[g_jammer]

Thanks for the comments Riptide,

Sorry for the confusion I caused with acute and obtuse, should of said sharp and soft. However, Acute and obtuse in this case are relative terms, and not literal since a LEO obviously wont be firing at your car door to try and clock you with LIDAR. They refer to soft and sharp angles relative to you.

A soft angle might be a LEO on a off ramp and you in the far left lane of a 8 lane highway at 1200 feet. At 700 feet, that angle becomes sharper, more so at 300 feet, at 100 feet even more so.

As far as cosine, wasn’t saying it is something to count on to save you. The point I was trying to make was to ease the fears of extreme angle attacks. At a angle that is so severe that the counter measure cant see it (which what the SaltyinNJ concern was), the LEO would be basically firing at you sideways & aiming more at your front quarter panel instead of the HL or CM.

And for detection, the infrared beam must directly enter the sensor of the transceiver, one way or the other, otherwise, a single head would be enough to defend any vehicle if it could "sense" infrared around it. It has been discussed many times on this forum that a main contributing factor for PT's in close range with a good counter measure such as the LI is that the countermeasure no longer is able to detect the beam and stops firing, which is something I 100 percent agree with.

Thanks :)

[Riptide]

Thanks for the comments Riptide,

Sorry for the confusion I caused with acute and obtuse, should of said sharp and soft. However, Acute and obtuse in this case are relative terms, and not literal since a LEO obviously wont be firing at your car door to try and clock you with LIDAR. They refer to soft and sharp angles relative to you.

A soft angle might be a LEO on a off ramp and you in the far left lane of a 8 lane highway at 1200 feet. At 700 feet, that angle becomes sharper, more so at 300 feet, at 100 feet even more so.

As far as cosine, wasn’t saying it is something to count on to save you. The point I was trying to make was to ease the fears of extreme angle attacks. At a angle that is so severe that the counter measure cant see it (which what the SaltyinNJ concern was), the LEO would be basically firing at you sideways & aiming more at your front quarter panel instead of the HL or CM.

This is true of well placed setups. However, I have seen many cars who have their sensors far to central or inward causing the sensors to lose sight of the beam much sooner than they should. Placement placement placement ;)

And for detection, the infrared beam must directly enter the sensor of the transceiver, one way or the other, otherwise, a single head would be enough to defend any vehicle if it could "sense" infrared around it. It has been discussed many times on this forum that a main contributing factor for PT's in close range with a good counter measure such as the LI is that the countermeasure no longer is able to detect the beam and stops firing, which is something I 100 percent agree with.
I see your point, I think what must be true then is that the 3mradian beam dimensions aren't exact. There has to be some IR outside of that radius (that is at a lower power obviously) otherwise the truspeed would eat everyone alive under 250ft even for straight on shots.


Thanks :)

.

[lugnuts]

I think the most gain is had by the additional receivers much more so than the added output. This is why something like the laser tamers appeals to me, double your receiving sensor coverage.



what is the status of those? we haven't heard anything in a while.