Requirements

Section Links: Technology | Requirements

Texas A&M University and the Texas Transportation Institute conducted a project to survey “existing electrified advanced transportation concepts.” It evaluated five systems for their technology readiness. The project report, “Dual Mode Vehicle and Infrastructure Alternatives Analysis,” by Christine Ehlig-Economides and Jim Longbottom was published in 2008. Included in it is a set of system requirements for dual mode transportation systems.

These requirements were recast as a list of “must” haves and “should” haves by Jerry Schneider of the University of Washington. We used his list in showing below how the BiModal Glideway system addresses the issue of system requirements.

MUSTS

1. Must provide mixed-use characteristics - accommodate freight, mass transit and personal vehicles.

Our approach: Bimodal has all three in the form of separate models produced by the automobile/truck industry under the criteria established by the bimodal central control agency. Freight and mass transit may use driverless vans stripped of all automotive components, e.g., engine, transmission, etc. for maximum economic utilization. They may also use vehicles which contain driver automobile capabilities. For increased economy the driverless model which runs only on the Glideway, may or may not have wheels for limited off-Glideway mobility. This would require special exclusive Glideway ramps and equipments for controlling unmanned bimodals at designated centers. These centers can be industrial or commercial. Industrial concerns can establish exclusive subsystems between mainline Glideways and their suppliers. Commercial operations can establish major centers for receiving deliveries from many locations and redistributing to the local community i.e., UPS. USPS, etc. or for transshipping to other destinations. Local municipalities can establish their own mass transit systems as needed using minibus bimodals. These vehicles would commute between exclusive off-line mass transit stations on an as needed basis. Minibus bimodals can be manned or unmanned depending on local circumstances.

2. Must have guideway speeds that have a constant velocity - guaranteeing reliability of travel times with traffic flow control and excess capacity designed to prevent impairment of the constant velocity feature (intercity speeds of approximately 130 mph, urban highway equivalents at 65 mph, urban arterials at 32.5 mph, and neighborhood local guideways at 16.25 mph; urban bypass routes could maintain 130 mph; vehicles may move in platoons [groups of 5-10] with 100 to 150 ft between platoons).

Our approach: This bimodal system  estimates 120 mph for the high speed line in order to meet nominal wind speeds of 60 mph, 2 % grades, with 8 driving wheels.  Lesser Glideway design speeds of approximately 90. 60 and 30 mph would be more appropiate for urban Glideways depending on purpose, grades and local congestion, etc.

3. Must be capable of modular, incremental acquisition and be scalable to a national network.

Our approach: This has always been my intent. To be successful, bimodal guideways needs to be universal, at least in the United States. They should  be modular in construction. They will be designed to facilitate modular assembly of standing structures and cross beams that can be laid similar to railroads using similar procedures -- pushing the construction ahead of the line, supplying materials from the line already laid.

4. Must be able to accommodate those with disabilities.

Our approach: To be accomplished by auto industry as they do now.

5. Must have safety that is better than automobile statistics - reduce high speed crashes to less than 5 percent of current highway performance for traffic converted to guideway.

Our approach: Bimodal will fail if we cannot do as near 100 % as is humanly possible. Fortunately, current technological innovation has exploded in electronics, controls, computers, etc. At the same time costs have dropped dramatically. It is now possible to achieve virtually total safety through the use of high reliability parts, redundancy, and total testing every time a vehicle enters the Glideway. This will be combined with close surveillance of the entire system through the central control agency.

6. Must be designed so that the reliability of vehicles on the guideway system renders the probability of breakdowns on the guideway to the range of 10 to 100 disabilities per 100 million vehicle miles with clear strategies for removal of disabled vehicles and their occupants.

Our approach: Effectively, the bimodal vehicle rarely breaks down. The Glideway has no moving parts requiring special maintenance. Repeated testing, close manufacturing tolerances of the bimodal system, critical review of previous breakdowns and immediate corrections are essential. The system won’t work unless possible breakdowns are detected and corrected before they occur. On a single lane Glideway extending 1000 miles with maybe 44000 vehicles on route (one-third of the maximum capacity), if a single vehicle breaks down the entire line stops and waits for instructions or information. If the vehicle is driverless, a pre-located emergency bimodal would be dispatched to the next off ramp after the incident. It would then back up to reach the disabled vehicle and take it in tow. Alternatively, emergency vehicles can lift a disabled vehicle from below the Glideway and lower it to the street to proceed in the street mode. All bimodals have the ability to proceed in an emergency at a slow speed under automatic or manual control to the nearest off ramp. In this example approximately 44000 vehicles would be diverted onto the local highways over a 1000 mile long area if the problem could not be repaired at the site. The system will have emergency procedures developed long before it is operational.

7. Must be economically competitive with an evolving baseline design of internal combustion engine/electric hybrid automobiles.

Our approach: Model for model it will cost more. But for the all-electric whose price goes up with range due to the cost of battery power which is not likely to come down due to shortages of the raw materials necessary, the bimodal price is a trade off – a shorter range under battery for unlimited long range at high speeds. While on the Glideway, vehicle batteries are being charged. Factoring in safety, time used for other activities instead of driving, time saved from congested traffic, and reduced costs per mile make bimodal an attractive alternative.

SHOULDS

1. Should use zero or ultra-low emissions vehicles.

Bimodal vehicles are zero emission vehicles excluding emissions from electric power producers. I cannot predict what form of power production will be used, wind, photovoltaic cells, ocean energy, natural gas, oil, etc.

2. Should be user scheduled - efficient and accessible 24/7/365, on demand.

Our approach: Bimodals will be available to be owned, rented, leased, sold, by the public; government, industries, etc. and would be under complete control of owners 24/7.

3. Should have throughput capacity of vehicles at least four times that of conventional highway lanes in the urban environment and eight times that of conventional highway lanes in the intercity environment - this requires short headway between vehicles and may dictate a requirement for more than tire/pavement frictional braking capabilities for emergency use.

Our approach: Bimodals traveling 60 mph in urban environment on Glideways at intervals of 20 feet would have a maximum throughput of 15840 per hour. 120 mph and 40 foot intervals would also yield 15840 vehicles per hour. This is far in excess of “should have” requirements. Bimodal vehicles use 4 pairs of steel wheels on steel rails. This gives bimodals 8 driving and braking wheels improving acceleration and deceleration friction capabilities.

4. Should have direct origin-to-destination service with no intervening stops while in automated guideway mode.

Our approach: All bimodal vehicles accelerate and decelerate on entrance or exit ramps prior to entering a main line where all vehicles are operating at the design speed of that line.  The only time any vehicle on the main line changes speed is in an emergency when all vehicles slow or stop simultaneously.  On entering a Glideway if a bimodal does not pass an internal test or does not meet design specificati0ons, it is automatically aborted to an off line prior to joining a predetermined open position on the main line.

5. Should have an elevated or underground guideway to avoid at-grade conflicts and minimize right-of-way requirements and noise/visual footprint of the system.

Our approach: We have always planned elevated/grade separated, with minimum rights of ways and small footprints, soundproofing rails and wheels and making system as unobtrusive a possible. Cost savings of going elevated include no policing, no street signs, no traffic lights, no parking concerns, no traffic accidents, no striping, right of way planning or maintenance, and no bulky freeway on-off ramps.

6. Should be compatible with remote automated parking systems.

Our approach: Our system requires more engineering design for loading and off-loading bimodal vehicle occupants while on a Glideway off ramp (or commercial rail sidings) for purposes of controlling the vehicles to proceed driverless to parking facilities, which may be some distance away. It is doable, needs analysis of which system is preferable.

7. Should be capable of single mode PRT operation for people movement and be cost-effective for low/medium density population areas (2,000 to 2,500 persons/square mile).

Our approach: Our mass transit system should suffice. Vehicles stationed at strategic locations can pick up passengers nearby and deliver them to selected stations. These PRT will be re-stationed by a central controller in response to real-time predetermined user demand.

8. Should be capable of operating in an automated (driverless) mode while on the guideway.

Our approach: It is our plan to use driverless vehicles for personal transit, mass transit, transporting cargo, mail, industrial and commercial purposes. A driverless bimodal can be a minivan with or without automobile functions. Stripped down vans can be used for cargo, mail, parcel post, etc. They can be loaded/unloaded at specified centers which only authorized bimodals could depart or enter and receive instructions. Similarly, mass transit vehicles can enter a given mainline with instructions to exit at specified stations to pick up or drop off passengers. Software can be designed which prepositions people mover vehicles stored at central parking structures to designated waiting areas in preparations for a flow of commuters to or from commercial areas. The concept should be designed by the Bimodal central agency and made available to all communities desiring their own PRT system. The PRT aspect of bimodal systems should be determined by local cities and communities and generally would support dense populations with outlying suburb commuters. The design speeds of bimodal PRT Glideways should be in the 30 or 60 mph range in dense urban areas where there will be frequent ramps and curves, 90/120mph between cities etc.

9. Should preferably have public-private financial backing for the new system - users repay capital, operating and maintenance, energy costs, and financial return to investors.

Our approach: A bimodal user pay these costs through charges to his/her electric utility bill.

10. Should maximize the use of existing rights-of-way and interface to adjacent conventional roads in a seamless manner.

Our approach: This requires considerable negotiations between the railroads, highway, all local, state and federal governments (and may be the killer of any proposed multimodal system). The bimodal system is designed to be as cost-effective as possible. This is accomplished by using minimum land space by utilizing a single lane, elevated tracks; vertical switches permitting high speed, close spacing between vehicles; and the same through-put density as a three lane highway at twice the speed. The BiModal Glideway is particularly well-suited for sharing rights-of-ways with highways, railroads, etc.

11. Should provide security and privacy for individuals or small groups traveling together by choice - door-to-door service in the same cabin.

Our approach: The BiModal Glideway system meets this requirement with personal vehicles, cars and minivans.

12. Should have an evolutionary path to the final network vision that is plausible - perhaps PRT/mass transit in urban areas and a terminal-to-terminal captive system for freight with later ability to join mass transit systems and freight links to create a full network, accessible to private dual mode vehicles.

Our approach: The BiModal Glideway system meets this the goal of this requirement. See No. 8 above.

13. Should have a guideway design that is modular to facilitate factory construction and on-site, easy assembly/replacement and accelerated build time with minimal disruption to adjacent activities.

Our approach: As stated in 10, design for cost-effectiveness. It uses modular concrete and steel, no moving parts, steel rails and wheels. The Glideway can be the most expensive part of any transit system, requiring space, materials, engineering, equipment, destruction of previous structures, etc. This is particularly so when the land has to be purchased. Bimodal is designed to be the least expensive possible with individuals and commercial entities paying for the vehicles and paying off the indebtedness for development/construction.

14. Should consider a triple lane guideway - one in each direction and the middle one for diverted traffic in event of maintenance/repair/contra-flow needs.

Our approach: I do not see how a middle lane could divert traffic from lanes going in opposite directions without very complex controls in event of a malfunctioning vehicle. We can develop a main line by having it double-decked above or below using vertical switching to clear a problem off our main line however I believe our system can prove to be so much safer than highways that an occasional delay could be acceptable. It should be rare. With sufficient ramps a broken down vehicle would never have to be moved very far, either under its own reduced power or by a rescue vehicle. A second rail would not help if there was a major break in the lines. Maintenance and repairs can be performed at specified dates and times, mostly by special vehicles checking tracks and bar-graph visuals at speed.

15. Should be able to accommodate cars of approximately the size/shape of today's conventional cars and about a 3,000 lb load per vehicle including vehicle and occupants (freight vehicles to handle two pallets with about 2,000 lb per pallet and allowing about 2,000 lb vehicle weight, two pallet sizes/shapes to fit within 5ft x 5 ft x 10 envelope; actual size and weight limits are to be optimized and negotiated through competitions and impact analyses).

Our approach: Like Bimodal plans, see 18 below.

16. Should be designed for all-weather operation without impact to performance or safety.

Our approach: Weather shields on both sides of Glideway protect from rain, hail, wind, and snow. Super storms require reducing speed on a specific involved rail to 30 or 60 mph or stop if necessary. Shields are shaped to deflect side winds up and over vehicles and protect electrical components, bar codes etc. Performance can be influenced by approaching tornados, extreme weather and controlled by the local bimodal control center by communicating and reducing speed for a specified tracks. Safety first.

17. Should use vehicles that use stationary electric grid power while mobile on the guideway.

Our approach: We plan on using an optimized power and propulsion system. Considering the magnitude of this system it is highly conceivable that power producers will be willing to work closely with the propulsion designers. This could provide a very efficient/effective transit system. Our power will be supplied by power producers through third rail and, possibly, other power pick up systems. The specifics have not been determined; several areas need investigation. All doable. Throughout our concept there are many areas with potentially good trade-offs which require extensive consideration before finalizing which is where we need federal, industry and scientific/academic support.

18. Should enable terminal-to-terminal automated/driverless freight movement.

Our approach: We can provide this with our system as is. Our main lines are capable to handle mixed models of bimodal vehicles. All are equally capable to interface with the Glideway. One exception is the driverless van for moving some forms of cargo and people which are captive Glideway vehicles and require special handling for entering or leaving the main Glideway. Once on the Glideway all vehicles operate the same way, they “read the bar graphs” for continuous information which determines their speed, acceleration, location, determining local operational practices, etc. This determines which driverless can go where and when any vehicle can prepare to exit on a desired ramp. Driverless only vehicles enter- exit on very specific ramps leading to secure terminal locations equipped for them.

19. Should have a guideway that optionally provides hardened infrastructure for electrical conduits and communications cables.

Our approach: This is part of our weather protection. The electrical and communication equipment are installed under the weather covers and protected by them. The details have not been developed like many of the details. I can justify the science but to decide one good system over another will require extensive system engineering and analysis.

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