Need ideas for Motion detection on a vehicle.

The next bit you can help with is in post 20 on page 2

Long story short, I'm tired of folks helping themselves to the fuel in my 18 wheeler. The tanks are situated under the sides of the vehicle and there is room above them to mount a sensor (possibly a PIR??).

I've looked into automotive style alarm systems. I just feel it would be overkill. If they want to steal the truck, so be it. I'll send them a thank you card. I've also looked into locking fuel caps. But they are easily circumvented by anyone with any determination at all.

I'm open to any ideas you folks might have. Basically, I want a sensor to activate if someone's hand covers the 4" diameter cap to take it off. When that happens, a very loud alarm will activate and some lights (parking and work lights possibly) will blink. At least that's the plan in my head right now.

It will, of course, be controlled by an Arduino. And probably just use relays for activating the alarm and lights.

I know very little about PIRs (Passive Infrared Sensor if anyone was wondering). So, is there a PIR that can handle Ohio winter weather? Of course, I could mount it inside a piece if 4" PVC pipe with a removable cap. Then just pull the cap off each time before activating the system.

Anyway, like I said, I'm open to ideas.

I assume the truck suspension is pretty stiff so a regular vehicle motion sensor wouldn't work, right?

With a PIT outdoors, I think there's just too much chance of something causing a false alarm. Cold temperatures would be fine because a PIR is sensing the motion or change in body heat. My home alarm sensors loose sensitivity on hot days when the air temperature is close to body temperature!

Of course, I could mount it inside a piece if 4" PVC pipe with a removable cap

You might be onto an idea there... Maybe a light sensor under a cap. You would need some sort of light source (at night) but a low-power LED might be enough.

If they want to steal the truck, so be it. I'll send them a thank you card.

:smiley: :smiley: :smiley:

Everything is wrong since me and my baby parted
All day long i'm walkin' 'cause i couldn't get my car started
Laid off from job and i can't afford to check it
I wish somebody'd come along and run in to it and wreck it

Come On, by Chuck Berry

Use IR. If your tanks are stainless, then just aim an IR source from the cab top to someplace near the fuel cap, and monitor the reflection with the Arduino. Or put some retro reflective tape on the gas cap and point an IR laser at that, then monitor the reflected beam.

I would also buy the locking caps just to slow them down.

Also, when the beam is broken, light up the tanks with a few flood lights.

I can think of some other scares you could put into the thieves with a piece of black PVC and a couple of servo motors.

Or you could go low tech and mount a chain to the gas cap. But the chain would be inside a plastic sleeve and connected to a digital input on the arduino. As soon as the gas cap is no longer on the tank, the digital pin would go high and set off the alarms.

SteveMann:
Use IR. If your tanks are stainless, then just aim an IR source from the cab top to someplace near the fuel cap, and monitor the reflection with the Arduino. Or put some retro reflective tape on the gas cap and point an IR laser at that, then monitor the reflected beam.

Same thoughts I had using the unit below.
Could quite easily house everything close by the cap in a mechanically substantial housing with a tube to direct the IR beam more to the rim of the cap for example.
Could also have the IR beams operating through a clear plastic cover for weatherproofing.

DVDdoug:
I assume the truck suspension is pretty stiff so a regular vehicle motion sensor wouldn't work, right?

Your assumption is correct. It barely moves when I climb my 230lb butt in to it. And there's no way taking a fuel cap off would move it.

SteveMann:
Use IR. If your tanks are stainless,

They are aluminum with unpolished caps. I doubt they would be reflective enough on their own. But the tape idea is plausible.

SteveMann:
I can think of some other scares you could put into the thieves with a piece of black PVC and a couple of servo motors.

If I were to catch them in the act I'd like to take a 4 foot long section of 3/4" black PVC and wear it out on their backsides!

bluejets:
Same thoughts I had using the unit below.
Could quite easily house everything close by the cap in a mechanically substantial housing with a tube to direct the IR beam more to the rim of the cap for example.
Could also have the IR beams operating through a clear plastic cover for weatherproofing.

https://www.ebay.com.au/itm/5-x-IR-Infrared-Obstacle-Avoidance-Sensor-Module-for-Arduino-Smart-Car-Robot/192622027183?epid=3022403874&hash=item2cd92ae1af:g:McoAAOSwj3Bba9to

I'll have to read up on that module after some shut eye. That might very well be the ticket. I'll have to think on how to get a good reflective surface as those caps are mounted at an angle. But if I go that route, I'll come up with something.

Thanks folks!

Anyone else can feel free to toss your ideas into the ring.

Connect a 470 Ohm resistor to the cap, hot glue it to the top of the cap, connect a male quick disconnect to the other end of the resistor. Connect a female QD to a wire leading to the Arduino (inside cab), fasten wire so cap cannot be rotated without breaking or disconnecting it. At Arduino, connect the wire to a 470 Ohm resistor connected to Arduino 5V pin, connect a jumper from wire to an analog input pin. When wire is connected to cap, ADC value will read about 511, if wire is broken or cap is unscrewed from grounded tank, ADC reading will go up near 1023, if wire is shorted to GND before resistor, ADC will go down near 0. Use those values to trip alarm.

If(analogRead(A0) < 400 || analogRead(A0) > 600)
{
  raiseHell:
}

If people are defeating locking fuel caps and steering wheel sticks, then you need a better place to park. Might be easier to hack an existing simple alarm setup than starting from scratch. The fuel cap as a switch contact is the simplest approach, but it is normally “closed” which is a little more complex than being normally “open” and closed to activate the alarm.

zoomkat:
If people are defeating locking fuel caps and steering wheel sticks, then you need a better place to park. Might be easier to hack an existing simple alarm setup than starting from scratch. The fuel cap as a switch contact is the simplest approach, but it is normally "closed" which is a little more complex than being normally "open" and closed to activate the alarm.

Well, it's not easy finding a place to park a 75 foot long and 31,000 pound (up to 80,000 loaded) vehicle. And I've parked it there for nearly 7 years without a single issue until recently.

I don't use a "steering wheel stick". So no idea if those work or not. But locking caps are defeated with one whack from a hammer and punch or a cordless drill.

Your thought on hacking a system got me looking at a few things along that line. And one thing I'm looking at in particular is a 12V siren like those found on Ebay for about $20 USD. I think something similar to those could be hacked to work with an Arduino. And should be loud enough to cause an individual to soil his knickers.

At this point, I'm just looking to make them rethink the whole "easy mark" thing.

DangerToMyself:
The tanks are situated under the sides of the vehicle and there is room above them to mount a sensor (possibly a PIR??).

What about a laser range finder (VL530LX type) positioned to 'look' through the fill opening. Calibrate on closed tank. Any greater distance indicates the cap is removed and you're seeing past that point into the tank. Lesser distances might indicate a hand unscrewing the cap.

You might go with something like below to monitor the fuel cap area, with the detector discretely behind the cab monitoring the fill cap area. Even one of the DollarTree $1 electronic window/door monitors probably could be modified to work with the cap. Numerous possibilities, probably the simpler, the better.

dougp:
What about a laser range finder (VL530LX type) positioned to 'look' through the fill opening. Calibrate on closed tank. Any greater distance indicates the cap is removed and you're seeing past that point into the tank. Lesser distances might indicate a hand unscrewing the cap.

I think you just found my sensor Mr. dougp. I'm thinking that will work perfectly. A bit pricey. But not nearly as expensive as the over $100 in fuel this numb-nut gets me for each time.

DangerToMyself:
I think you just found my sensor Mr. dougp.

Good deal.

I also thought later since the sensor is I2C you could even add some code to sense a communication loss with the module, in the event the miscreants discover the sensor and yank it out. Even blocking it with a piece of tape could be sensed. Several possibilities.

Let us know how it works out.

dougp:
Good deal.

I also thought later since the sensor is I2C you could even add some code to sense a communication loss with the module, in the event the miscreants discover the sensor and yank it out. Even blocking it with a piece of tape could be sensed. Several possibilities.

Let us know how it works out.

Awesome. I never would have thought of that.

Of course, like every circuit available, there are Chinese replicas of the AdaFruit VL53L0X (I have no idea who created it to begin with). But the VL53L0X is quite a bit cheaper on eBay (even cheaper if I wanted to wait on the slow boat). So, I have a few of them in my shopping cart. I just have to come up with a mounting solution (small plastic boxes) for the 2 sensors. They'll be subjected to water/ice. But shouldn't have any rocks or the like tossed at them. Too much in the way for that to happen. Possible, but highly unlikely.

I, also, have a siren in my cart (12V 100W 7 Sound Car Warning Alarm). I "should" be able to hack those buttons so the Arduino can control them.

I'll use one of my knock-off Nano boards mounted in a small enclosure to help keep wiring contained. And I still have one or 2 that haven't had the headers soldered on yet. That will let me solder the wires directly to the board and reduce the chance of them vibrating loose while traveling.

I need a power source for the Arduino. So, have to look into the best way to use the 12V available. The system will only be powered while it's parked. So, I think I can get away with using a cigarette lighter plug (I have a few of them on hand). I've read that the Nano can take 6-20 volts on the VIN pin. If that is not true, LET ME KNOW!

Rubber grommets and wire loom! Can't forget those.

I'm just trying to think this all out ahead of time. So, if anyone sees something I'm forgetting, or not taking into account, speak up.

Be sure to read the section of the datasheet for the sensor about placing glass, or whatever, in front of the aperture for the beam to exit/enter.

dougp:
Be sure to read the section of the datasheet for the sensor about placing glass, or whatever, in front of the aperture for the beam to exit/enter.

I read that elsewhere. I haven’t dove into the datasheet (yet). Probably should before I order it though. Also, read where it’s advised to use separate glass for each side with a barrier between to avoid reflections. That might be fun trying to accomplish. lol

You might also consider hiding a game cam or a small surveillance cam to see what is going on. I don't know the image quality, but there are some small and inexpensive motion sensitive cams being advertised. Kind of like the doorbell cams.

Have you ever heard how loud someone screams when they get a good shock when they don't expect it?

A guy I knew who owned a business in a difficult part of town and people took joy at peeing on the handle to his back door after leaving local bars. The camera did not help, in fact more people seemed to want to be in movies and would use hi door as a urinal. The guy went to Fleet Farm and got n electric fence power supply, having weed burning capabilities. It took a little bit of bicycle tire inner tubing and silicone glue to electrically isolate the door knob so the power supply would not short to ground except through the path provided by the urine. The owner put up a large sign saying it was dangerous to approach any further. It is too bad that there was no sound recording to accompany the video, but given how wide the mouths were opened it is assumed that the people were in an advanced level of agony, most were at least 3 feet away from the original position on their butts still emptying their bladder.

Now for the Mr Wizard warning: "Don't try this at home children"

Remember electricity can be your friend and used for a wide variety of applications.

“It took a little bit of bicycle tire inner tubing and silicone glue to electrically isolate the door knob so the power supply would not short to ground except through the path provided by the urine.”

Interesting story, but the “bicycle tire inner tubing” kind of gives it away.

wwbrown:
Have you ever heard how loud someone screams when they get a good shock when they don't expect it?

A guy I knew who owned a business in a difficult part of town and people took joy at peeing on the handle to his back door after leaving local bars. The camera did not help, in fact more people seemed to want to be in movies and would use hi door as a urinal. The guy went to Fleet Farm and got n electric fence power supply, having weed burning capabilities. It took a little bit of bicycle tire inner tubing and silicone glue to electrically isolate the door knob so the power supply would not short to ground except through the path provided by the urine. The owner put up a large sign saying it was dangerous to approach any further. It is too bad that there was no sound recording to accompany the video, but given how wide the mouths were opened it is assumed that the people were in an advanced level of agony, most were at least 3 feet away from the original position on their butts still emptying their bladder.

Now for the Mr Wizard warning: "Don't try this at home children"

Remember electricity can be your friend and used for a wide variety of applications.

:smiley: :smiley: :smiley:
Great idea!

But unfortunately, I don't relish the thought of spending thousands of dollars and countless hours on a lawsuit. Especially one that the idiot judges around here would find in favor of the thief. Idiot people win frivolous lawsuits brought on by their own stupidity every day it seems.

Got the siren in the mail today. OMG is this thing loud! It won't have any issues making someone lose control of their bladder. LoL