• Advanced traffic responsive traffic signal control
• Automated sign control system.
• 200 camera video surveillance system.
• Sophisticated electronic transportation monitoring systems.
• Time critical geographic information system (GIS)
• Automated transportation information system.
• Integrated transit and traffic operations.
• GPS and ocher technologies based vehicle tracking system.
• Automated incident management system.
• Aerial surveillance operations.
• Automated integration with police / fire computer aided dispatch systems.

The existing TMC is staffed from 6:00 AM to 1 1:00 PM 365 days a year. As staffing allows the TMC is planned to be staffed on a 24 hour basis.

Initially a traffic engineer would fly in a contracted airplane with a contracted pilot each morning and evening rush hour and would use a portable radio to radio problems to the Transportation Management Center. Within a few months of the start of the project the Department of Transportation entered into a contract to lease an airplane on a 24 hour basis and the Department of Police assigned two Sergeants with existing commercial pilot licenses to fly the airplane. A radio pack was designed and constructed by county personnel to provide multiple communication frequencies that allow the observer to contact most police, fire, and transportation agencies in the Washington D.C. area including state highway and police agencies.

In 1992, because of budgetary reasons the Montgomery County Department of Police had to withdraw the two pilots from the project. The Department of Transportation contracted pilot services with the company supplying the aircraft. The project has been solely operated by the Department of Transportation since 1992.

Montgomery County uses a single engine high-winged airplane. The airplane was chosen over a helicopter because of operating costs. The airplane can be operated for approximately $80 per hour versus $300 per hour for a helicopter with similar performance capabilities. It was decided that for 99 percent of and landing capabilities of a helicopter. Five years of experience has proven this to be true.

Over the past five years the airplane used by Montgomery County has chanced to meet the requirements of the county. Initially, the county leased a Cessna 172, a small four passenger airplane with limited room for personnel, equipment and passengers. In 1990, the county contracted for a Cessna 182. The Cessna 182 is a larger four place airplane with sufficient room for personnel, limited equipment, and passengers. The Cessna 182 was replaced in the late 1993 with a Cessna 206. The Cessna 206 is a six place airplane with excellent load carrying capabilities. The Cessna 206 was required to be able to carry the additional equipment associated with on board live video broadcasts.

The aerial surveillance project has been a critical part of the Department of Transportation's transportation management program. On a typical flight the airplane either finds or quickly responds to incidents that impact the transportation system. The observer contacts the appropriate authority to respond to the problem, notifies the TMC to adjust traffic signals, etc. in the area of the incident, and directly notifies the airborne radio traffic reporters of the problem. The airplane is known as MC-10.

MC10 performs on a regular basis traffic management functions, police surveillance, environmental protection activities, assists fire and rescue in locating fires in the rural and other hard to access areas. MC-10 is used for still and video photography.

Providing a live video picture of what was happening to the TMC would help managers on the ground make appropriate decisions as they would have the "big picture" which cannot be readily described over the radio or by land line. Multiple ground units would have to describe a situation and their description is usually controlled by what they can actually see, which is very limited on the ground.

In July, 1991, after several meetings the State of Maryland, Montgomery County, the State of Virginia, and Fairfax County, Virginia delivered a proposed demonstration project for live aerial video to the Federal Highway Administration (FHWA). The demonstration project would be divided into stages, the first would be to test live video from a helicopter and from a fixed wing airplane. Other stages were proposed enhancements to the information gathered by the aircraft. Fairfax County, Virginia would install a video camera system on one of its police helicopters and Montgomery County, Maryland would implement live video capabilities in its fixed wing airplane.

After FHWA approved a 50/50 funded demonstration project for stage one, Montgomery County Department of Transportation prepared specifications and advertised through the normal bid process for a contractor to supply and implement the specified video system. The normal bid process in Montgomery County takes six months. Because of limited knowledge by the county's procurement office of the type of company that would be qualified and improper advertisement of the bid the county received no bids. The Department of Transportation was then authorized by the county's Chief Administrative Officer to contact capable vendors directly and obtain bids. Four companies submitted bids and the Department of Transportation negotiated a contract with the qualified lowest bidder. A contract was signed in April, 1993 with N-Systems Incorporated (NSI) located in Columbia, Maryland.

Some equipment was ordered and other components of the system were designed and manufactured by NSI.

During the Summer and Fall of 1993 installation and testing of the system began. Testing had to be stopped when the county upgraded the airplane from the Cessna 182 to the Cessna 206. As part of the contract for the Cessna 206 a new console was to be constructed by the airplane contractor and installed in the airplane. This console would contain the multiple radios, video monitor, S-VHS recorder, GPS receiver, and microwave transmitter. The console was completed at the end of December, 1993. As of the date of this article, the console is temporarily installed in the aircraft with permanent installation scheduled by the end of January, 1994.

• Airplane
  • Microwave transmitter
  • GPS receiver
  • Color video camera
  • Color video monitor
  • S-VHS player / recorder
  • Microwave antenna

   

• Transportation Management Center
  • Microwave receiver
  • Automated tracking antenna
  • Antenna control system
  • Color video monitors
  • S-VHS editing system

   

• Portable Ground Transmit and Receive System Transmit
  • Microwave transmitter
  • Microwave antenna
  • Color video camera
  • Tripods
  • Batteries
  • Receive (3 sets)
    • Microwave receiver
    • Microwave antenna
    • Color monitor
    • S-VHS player recorder
    • tripods
    • batteries

Should the automatic tracking fail the antenna on the roof of the EOB can be positioned manually from the TMC through a touch screen control unit. Audio can be sent over the microwave system from the airplane to the TMC.

In the airplane an industrial grade color video camera is mounted so as to aim out of the side window behind the observers seat. The observer can monitor the video system and record what the camera is viewing. An additional monitor is mounted so the pilot can also see what the camera is viewing and adjust the track of the airplane accordingly.

The portable transmitter system provides the county the capability to transmit live video from the scene of an incident or other activity directly back to the TMC. The portable system uses the same type of microwave transmitter as is installed in the airplane. A directional microwave antenna is mounted on a tripod and is aimed in the direction of the tracking antenna on the roof of the EOB. Since the portable unit is using the same antenna as the airplane both systems can not be operational at the same time. When the ground unit is in use the staff in the TMC moves the roof mount antenna until an acceptable microwave signal is received.

The ground based portable receivers can receive transmissions from the airplane or from the ground based transmitter. The portable receiver antenna can be used as a directional antenna to receive the signal from the airplane when the airplane is in the distance or can be pointed straight-up and will receive transmissions from the airplane as it circles overhead.

The portable units will be used by the Maryland State Highway Administration, Montgomery County Department of Transportation, and one unit will be installed in Montgomery County's Police/Fire and Rescue Command Bus. The Command Bus is sent to major incidents to serve as an on-scene command and communication center.

As part of Montgomery County's automated transportation information system the video and audio received from the airplane or ground unit can be sent over the government network to other agencies. The video and audio can also be sent from the TMC over the subscriber cable television system into homes and businesses. The on-air television broadcast stations are presently connecting to the TMC's system and will be able to receive the same video and audio and then retransmit as part of their news broadcasts. The airborne and portable video can be combined with video from the fixed video surveillance system.

Preliminary testing indicates the airborne system performs exceptionally well as long as a good signal can be received. Initial tests indicates that the video signal can be received from the airplane while it is over any point in Montgomery County as the airplane flies at its normal altitude of 1000 feet above the ground. There are certain areas of the county where other microwave signals are interfering with the signal from the airplane. This may be addressed by going to another frequency. Tests of the portable receivers have been very successful. The directional mode allows personnel on the ground to track the aircraft manually in the distance. The distance the airplane can be received is dependent on the altitude it is flying and if any solid objects or terrain block the microwave signal.

The portable ground transmitter works well as long as terrain or solid objects do not block the microwave signal. Testing has been successful from distances up to 3 to 4 miles even though the antenna is mounted on a tripod sitting on the ground. Extended distances and increased areas of coverage could be possible with a 40 foot telescoping mast for the antenna. As part of Montgomery County's transportation management program an incident management and transportation analysis van is planned. This van will be specified with a telescoping antenna and other equipment to integrate with the airborne and ground based video system.

Presently, the camera mounted in the airplane is not stabilized so image steadiness is dependent upon how turbulence impacts the airplane. When the camera is zoomed in closer any movement is exaggerated. The first stage of the demonstration project was to demonstrate the use of live video and how well a microwave signal can be sent from an airplane to a traffic management center. Improvements to the video image can be greatly enhanced by installing a gyro-stabilized camera mount.

Montgomery County has been reviewing and testing a stabilized video system which can be readily adapted to the existing microwave system and could be mounted on the Cessna 206 as it was recently certified and tested on a Cessna 172. The stabilized system is manufactured by Wescam, a major supplier of stabilized film and video equipment used by the motion picture and television industry. The system mounted on the Cessna 172 has been tested by Montgomery County personnel. The Wescam system has been used to track individual vehicles from the Cessna 172 and will readily allow the operator to fix the camera on an incident or intersection. The stabilization maintains a steady image even in severe turbulence.

Montgomery County's aerial surveillance program is critical to the county's transportation management program. The airborne video system greatly enhances the aerial surveillance program. The airborne video system provides ground personnel, including decision makers, the ability to make educated decisions on what actions should be taken because they see the total impact of an incident or event on the transportation system. The video images can be shared with other agencies and the media. This sharing of the "big picture" helps other agencies respond to situations and allows Montgomery County Government and the media to disseminate improved information to the public.

Montgomery County has just started testing the airborne and ground based system. Initial findings indicate the system can be enhanced by installing a gyrostabilized camera. Low light capabilities could be added for night time operation. Fixed remote receiver sites would improve reception in those areas with interfering signals.

Even the initial tests have proven that "live" broadcast quality video from an airplane can be done.

The "live" video can be a valuable tool to help manage traffic on a daily basis and during incidents or special events.

Montgomery County plans to complete its evaluation of the airborne system during the first quarter of 1994 with results forwarded to the Federal Highway Administration soon after. Montgomery County hopes to work with the State of Maryland and the Federal Highway Administration to further enhance the aerial video project.