Nomadic
devices
Nomadic devices are probably not suitable for
ISIG since the volume of traffic and the latency in cellular communications could be
limiting factors
Since DSRC is being used for safety applications,
ISIG can listen for BSM messages at an intersection with little additional
effort.
Level
of Market Penetration
EVP and TSP are low hanging fruit as these fleets
are generally owned and operated by public agencies.
FSP is similar, but the fleet is diversely owned
and operated.
Early results indicate that about 25% market
penetration is needed for ISIG and PERF MEAS
PERF MEAS could be effective with lower market
penetration if longer time frames are considered (to get several observations)
Possible
Effects of Communication Errors and Latency
The use cases for priority requests (EVP, TSP,
and FSP) include acknowledgement confirmation, so random communication loss should
not have an impact unless complete loss occurs.
A few seconds of latency in the priority use
cases will only result in slight impact to performance.
Latency in ISIG can impact the Dilemma Zone
protection and signal performance.
The
marginal benefit with data from existing sensors
ISIG benefits from existing detection when the
market penetration is low (or when the traffic volume is low and market penetration is
medium)
Vehicles need to be observed (detected) to alert
the controller that a vehicle needs to be served.
Current EV and TSP sensors provide some level of
data that can be used in priority applications, but the standards (SAE) support
system level interoperability and the algorithms (EVP, TSP, and FSP) are more advanced
than existing algorithms
The
modal benefits of connected vehicle data are critical
Knowing that a vehicle is transit, truck, or EV
can significantly impact the ability to provide safe priority
Signal control can benefit significantly using
connected vehicle data to measure queue length, saturation flow rates, startup lost
time, etc. These measures are not available without CV data
Pedestrians (and bicycles) will be significant
beneficiaries (using cellular)
Performance observation is not possible without
CV data [This could be one of the biggest benefits and doesnt depend on only
MMITSS it should be part of every DMA]
Potential
Deployment Impacts
Near
Term Impacts
Significant benefits for priority control: EVP,
TSP and FSP in an integrated, multiple vehicle environment
Mobility for disable pedestrians using the PED
SIG application
Mid
Term Impacts
Performance Observation by Mode (near term for
EVP, TSP, and FSP)
Improved Signal Control (ISIG) as market
penetration increases
Long
Term Impacts
Reduced dependence on complex infrastructure
based detection systems (only 1 RSE required)
Ability to adjust traffic control policy
(priority) based on mode (and movement)