GARAŽA forum

Odlika Vascara 5000 SB, pored velike preciznosti i nemogućnosti ometanja, jeste i prilična ”samostalnost” jer je ovaj sistem vezan sa automobilom samo preko napajanja i signala iz računarske jedinice motora ”matičnog vozila” koji mu pruža informaciju o brzini kretanja samog presretača. Jednostavan princip rada omogućuje ovom uređaju i ogromnu preciznost jer se merenje brzine zasniva na osnovnim referentnim tačkama, koje mogu predstavljati bilo šta na putu.

Na primer, prilikom početka praćenja, vozeći za automobila koji krši propise, dovoljno je da operater u vozilu startuje merenje, a kompjuter automatski izabere neku referentnu tačku na, oko ili iznad puta (bilbord, nadvožnjak, veliki saobraćajni putokaz, drvo itd.), pre nego što praćeni automobil prođe pored ili ispod nje. U tom momentu, sistem je uzima za koordinatu i kada presretač koji prati vozilo, prođe pored iste, jednostavnom računicom uz pomoć vremena i pređenog puta, dobija se prolazna brzina vozila.

Upravo ova jednostavnost i brzina rada čine Vascar 5000 SB jednim od najboljih uređaja u praksi. Iako su se pojavile priče da je ovaj uređaj moguće ometati, to možemo odmah demantovati, jer sam princip rada ne ostavlja mesta sumnji. Naime, Vascar 5000 SB ne emituje nikakve zrake ili impulse da bi ometanje imalo smisla i bilo efektno - on jednostavno snima i proračunava vreme i brzinu kretanja objekata.

H4wkeye napisao:

Grujic napisao:Pa PolCam ne radi bas na istom principu kao Vascar

Ja mislim da su slicni u tome kako mere brzinu. U svakom slucaju ne mozes da ometas sa nekim anti-radarom i tim sranjima.

PolCam EC-II is a user friendly, multipurpose in-car video recording system, developed for traffic control and speed measurement using Doppler Radar technology. Unique system architecture is designed so to be installed on almost any vehicle. The advanced technology makes it possible to use it in any weather conditions, day and night.

Grujic napisao:U kom smislu ljudski faktor?

edit:

H4wkeye napisao:

Grujic napisao:Pa PolCam ne radi bas na istom principu kao Vascar

Ja mislim da su slicni u tome kako mere brzinu. U svakom slucaju ne mozes da ometas sa nekim anti-radarom i tim sranjima.

Pa baš tu nisu slični.

Verovatno ima više verzija PolCam-a, ali evo sa sajta njihovog

PolCam EC-II is a user friendly, multipurpose in-car video recording system, developed for traffic control and speed measurement using Doppler Radar technology. Unique system architecture is designed so to be installed on almost any vehicle. The advanced technology makes it possible to use it in any weather conditions, day and night.

Inače, vidi se razlika na prvi pogled, kada je SAT išao sa njima pa su demonstracije radi izmerili brzinu vidi se da meri mnogo brže nego ostali koji moraju da imaju distancu pređenu

Here's how it works. Assume you're driving down a stretch of divided Interstate roadway. Coming at you is a state trooper with VASCAR. As he spots you he'll look for a reference point where he can begin timing you. Many states paint broad white stripes across the road for this purpose but if the trooper is in open country he's unlikely to have these available. So he will improvise and make use of other landmarks: tar strips, road signs, and shadows across the road all serve nicely. At night he will use the flash of your headlights against reflective road signs, median barriers, reflective mileage markers or even discarded soft drink cans at roadside. As the front of your car passes his mark the trooper flips on his time switch, activating the internal timer. As you continue to approach him he will choose another reference point, wait until you hit the mark then turn off the timer. Now your elapsed time between the two reference points is stored in the computer.

The next step is simple. He passes you, U-turns through the median and drives to the first reference point. Here he turns on the distance switch, travels to the second point and turns it off, recording the distance you traveled. The computer handles the number crunching and displays your average speed to 0.1 mph. The hardware's accuracy tolerance is plus or minus 1 percent. Since at freeway speeds the minimum recommended clock is one tenth of a mile, the operator can miss his marks by a fair distance and still get a clock within a 2-3 percent accuracy window.

Since the operator has to take an active role in using the device, VASCAR has never been popular with lazy officers. But in the hands of an aggressive trooper, especially when used from an unmarked car, VASCAR can be deadly.

Knowing how meeting clocks are done, study up on the others:

Dzoni_m napisao:Vec smo par puta pricali o tome kako radi Vascar. Nema sta na sudu ti da dokazujes nikakav ljudski faktor. Ljudski faktor samo "klikne" da krene merenje i to je sve. Uredjaj ima atest i "bazdaren" je. Ti uredjaji su postojali i u manuelnoj formi jos pre 50 godina. https://en.wikipedia.org/wiki/VASCAR