RoadRAMP MiniTwin BYPASS
Where road tube just isn't enough.
Portable axle sensors with lane isolation and lane discrimination to eliminate “shadowing” for more accurate volume & classification counts on busy City, County & State roads.


The Problem

Volume, speed and axle vehicle classification on busy two and four lane sites, using road tube or mini tube installed in  “A minus B” or “long & short tube” configurations, becomes increasingly inaccurate when peak traffic volumes exceed 200 vehicles / lane / hour.

The problem is “shadowing” – as when two vehicles in their separate lanes, simultaneously strike the installed axle sensors sending invalid and unclassifiable signals to the traffic counter. This is a problem that becomes more severe as the traffic volume increases.

The Solution

The solution is to use RoadRAMP MiniTwin BYPASS Units for volume, speed and classification projects on busy, two-lane City, County and State roads and also four-lane divided highways, when peak traffic volumes exceed 200 vehicles / lane / hour.

RoadRAMP MiniTwin BYPASS Units provide true lane discrimination, eliminate “shadowing” to give highly accurate data for volume, direction, speed and classification counts, in each separate lane. The accuracy of the data being limited only by the speed and sensitivity of the traffic counter.

RoadRAMP MiniTwin BYPASS Units are compatible with most available pneumatic traffic counters. They are quickly installed using the same materials and similar installation techniques as used for installing regular road tube.

RoadRAMP MiniTwin BYPASS Units Features:

  • Eliminates "shadowing" on busy, multi-lane sites
  • Ideal when peak traffic volumes exceed 200 vehicles per lane / per hour
  • Provides separate and independent axle sensors in each lane
  • Gives true lane discrimination for better classification results
  • Yields highly accurate classification data in each lane
  • Installed with existing materials and techniques
  • Compatible with most pneumatic traffic counters
  • Faster, simpler installation for multi-lane layouts
  • Less time in the road means increased safety
  • Reuseable for multiple installations

Design Features

Each 30ft. RoadRAMP MiniTwin BYPASS Unit (see Fig 3) consists essentially of two mini road tubes (0.185” i.d.) assembled as a single, compact component only 0.850” wide x 0.375” high. Each mini tube is assigned to one of two lanes and is identified by a colored tube connector to simplify installation. (Fig 4)

  • The left tube (black connector – first lane), consists of two sections
  • An initial 15ft. section, which is the first lane, axle sensor
  • A second 15ft. section, which is redundant and not used
  • The right tube (white connector – second lane) , also with  two sections
  • An initial 15ft. BYPASS or blocking section with an “incompressible", flexible inner tube that is installed across the first lane and connects to the second lane axle sensor
  • A final 15ft. section which is the second lane, axle sensor
   
Use MiniTwin BYPASS Units for volume, speed and classification on busy two and four-lane roads when peak traffic volumes exceed 200 vehicles / lane / hour
 
MiniTwin BYPASS Units are for use on two to four (divided or undivided) lane City and County roads
 
Fig 3 - Mini Twin BYPASS Unit
(30ft. long x 0.850” wide x 0.375” high)
 
Fig 4 - Connectors
-Black connector for lane-1
-White connector for lane-2
 
Fig 5 - “Figure 8” wire loop is adjustable to suit road width

The “incompressible” bypass or blocking section allows pneumatic signals, generated by traffic in the second lane, to travel through the "incompressible" bypass or blocking section in the first lane and pass to the traffic counter on the shoulder with no interference from traffic in the first lane.

Signals generated by traffic in the first lane, pass directly across the shoulder to the traffic counter. In this way and with separate, independent axle sensors in each lane, Mini Twin BYPASS Units achieve true lane separation and very accurate vehicle classification counts, regardless of traffic volumes.

RoadRAMP Mini Twin BYPASS Units are installed using the same materials and similar installation techniques as used for installing regular road tube and mini tube. The 30ft units are sufficiently oversized for each end to be secured well away from the traffic flow, providing better personal safety for the installers.

RoadRAMP Mini TwinBYPASS Units are compatible with most pneumatic traffic counters, as supplied by -

JAMAR - IRD - TimeMark - Diamond - Metro Count - MITRON - PEEK - Others

RoadRAMP Mini Twin BYPASS Units are quick and easy to install, with the installing technician spending less time on the road.

Click here to download RoadRAMP MiniTwin BYPASS installation instuctions (MTB Installation.pdf)

 

 

 
     
 
Please contact info@roadrampsystems.com with questions or comments
Copyright © 2006 Roadway Data Systems Corporation