Synergies Between PRT and Driverless Cars

Prof. Em. Ingmar Andreasson

LogistikCentrum AB

Ingmar Andreasson

• Bus network planning 1970:ies

• Taxi fleet management 1980:ies

• Driverless transit since 1990:ies

• PRT design and control patents

• Professor Traffic simulation KTH

• Vice President Advanced Transit Association

New transport modes are needed

• Use of private cars has decreased

• Fewer youngsters take driver’s license

• Car industry in crisis

• Energy crisis

• Climate crisis

• Congestion

• Lack of space for roads and parking

Peak car (Britain)

Some development trends

• Electric cars

• Car-sharing

• Co-modal trip planners

• Autonomous cars

• Driverless transit

Google car

NHTSA Levels of automation

• L1: Function specific (ex: braking)

• L2: Combined functions (ACC+lane)

• L3: Limited self-driving – Driver can cede control under conditions– Google car, platoons

• L4: Self-driving – Can run empty, shared or public– In parking lots, reserved lanes

SARTRE project

0.3 sec headway (6 m gap) @ 85 kph in mixed traffic

Driverless transit

• Vehicles can be small

• Short headways

• Individual, on demand

• Non-stop between transit stops

• Reserved right-of-way

⇒Personal Rapid Transit

Morgantown PRT since 38 years

• 73 vehicles

• 80 million passengers

• No serious accident

Modern PRT

• Small, light

• Short headways

Automated Transit Networks (PRT)

• Steering, braking, navigating since 1975

• Reserved lanes or separate “roads”

• Empty repositioning by demand

• Excellent safety

• Available to all (age, disabilities, license)

• Low energy, no pollution

Synergy contributions from cars

• Resources for development

• Low-cost sensors

• Better batteries

• Economies of scale

• Communication protocols

• Acceptance of short headways (0.3 vs 3 secs)

• Strong industry lobby

Economies of scale

100 000 € 100 000 € 30 000 €

Contributions from PRT

• 38 years operating experience

• Proven safety

• Standards and certification

• Ride-sharing strategies

• Empty vehicle management

• Safe and smooth intersection control

Ride-sharing patterns

O D1 D2

Same destination

Two destinations

Two & pick-up

(Pick-up & continue)

Vehicle surplus/deficits

Vehicles in station

– Vehicles allocated to depart

+ Vehicles (loaded or empty) on way in

– Passenger parties waiting

– Expected passengers during call time

Management of empties

1. Call/send based on surplus/deficit

2. Swap destinations so longest waiting

passenger gets nearest

3. Send remaining to largest deficit

Intersection control

• Approaching vehicle calls controller

• Controller allocates passage time-slot

• Notice of passage time sent to vehicle

• Vehicle adapts speed to fit slot

• Individual greens to pass

• = Merge control in asynchronous PRT

Dual-Mode

Car development

• Manual plus Driverless on guideway

PRT development

• Guideway PRT plus manual control

⇒Convergence of Car and PRT

Dual-mode cars

Dual-Mode is attractive

• Door to door travel

• Guideways and access can be widely spaced

• Need not be connected to network

• Attractive along arterials with queues

• Allows gradual implementation

• Vehicles private – less public investment

• No operator – V2V control

• Public system possible on guideways

Dual-Mode infrastructure

• Guideway = public road

• Relieving road congestion

• Open for equipped and checked vehicles

• For small vehicles only

• Less investment than new roads/lanes

• Small footprint

• Suitable for battery charging and debiting

Conclusions

• Embrace Driverless Cars and PRT

• Developments supporting each other

• Both converge into Dual-Mode

• Network of reserved roads/lanes/guideways for

autonomous vehicles

• Private and public transport on same network

• Automated taxi – “aTaxi”

• Eventually in mixed traffic