Usability
The convenience and usability of the portable ATIS was measured based on setup times, ease of system use, and usefulness. Setup times were observed by a student researcher at the beginning of the showcase. The goal of this project was to have a fully functional system deployed within four hours. This includes site specific system modifications, placement, calibration, etc. This goal was based on the assumption that a system was fully functional and “off-the-shelf.” Only the Adaptir system was fully functional; the other three systems operated off-line. Adaptir is an open ended system that can be utilized for a number of uses and required some tailoring for this specific application. Additionally, software had to be modified for the specific demonstration location. These activities were completed by the vendor and the level of effort was not monitored. Research staff were only able to monitor the actual field setup times (discussed further below). Note, that these setup times do not include some of the site-specific calibration completed by vendors, nor does it include configuration of communication equipment for the off-line systems.
The Blufax system came preassembled and had the least hassle. No maintenance was needed after the initial switch of the power button. Setup time was simply the travel time to the site locations plus about 5-10 minutes to lock the system to a secure object and turning on the unit.
The iCone units also came preassembled and offered little trouble. The iCone units weigh 60 pounds each and needed to be loaded onto a truck to be transported to the site locations by at least two people. Once at the site location, the iCone units were turned to face the oncoming traffic at approximately a 45-degree angle and the power switch was turned on.
The LPR cameras took the most time for setup. The cameras needed to be mounted on the trailers so that they were able to easily pick up on license plates in the near lane, the software needed to be calibrated, and the wiring had to be connected to the power source/communication system. This was all done prior to leaving the shop; however, it could have been done in the field and would take an additional 20 minutes. Each trailer took approximately 30 minutes for setup and calibration. An extra two hours was spent troubleshooting the problems with the LPR camera at location 3 before it was determined the cable was faulty.
The speed radars for the Adaptir system were set up and ready on the first day of the showcase. The timeframe for mounting and connecting the system was approximately 30 minutes per location. The antenna had to be relocated to a higher vantage point on the trailer to ensure the best communication line of sight. This was done prior to the first two trailers leaving the shop and took about 15 minutes. The RTMS radar also had to be relocated to a specific angle and was therefore remounted, which delayed the deployment of that trailer for another day.
Because several systems were attached to individual trailers, total setup time for a location ranged between 10 and 30 minutes, depending on drop-off location accessibility and the preassemble status. The trucks could only hitch up two trailers at a time, so multiple trailers would mean multiple trips or multiple drivers. The positioning of the trailers proved to be the most time consuming due to accessibility. The actual powering-up took less than five minutes, waiting for the indicator lights to verify the system was working and collecting data. Systems without need for the trailers (Blufax, iCone) would have an estimated setup time of less than five minutes, as their systems are essentially self-contained.
In several conversations with the on-site system manager, he stressed the LPR system needed the most maintenance of the four systems. Hours of setup time would have been saved if all the equipment was checked out first to ensure all the cables and cameras were working properly before they were brought to the project site. In addition, the manufacturer of the LPR system has six separate configurations for data collection, and they were not set up for an offline collection. He noted that the other three data collection systems worked well and required little maintenance or troubleshooting time.
In several conversations with a Caltrans District 2 representative, he noted that the Blufax system seemed like the most realistic and reliable system for use in a rural area like District 2. His one concern was regarding the detection rate and how it would be affected by the limited cell coverage in the district. He also noted that an external power source would need to be used to limit the recharging of the units.