Technology used in the Milpitas PRT project was developed over decades by scores of people working to create a system that satisfies a long list of performance criteria. While the design is detailed in the ITNS Business Plan, most people are satisfied learning about the high-level aspects of PRT capacity, cost, and hardware.
Find a clear overview of public transit metrics and trends of service provided/consumed in the United States at National Transit Summaries and Trends (NTST).
Self-Conflicted Public Transit
Consider how self-conflicted conventional mass transit keeps getting in its own way.
- Adding stations to increase access adds stops – which slows down service.
- Increasing capacity with larger vehicles requires bigger, more expensive infrastructure.
- Bigger infrastructure is best laid out along dense corridors.
- Passengers must first get to the corridor where they await and ride the next vehicle, then somehow get to their ultimate destination.
- Adding a new line adds a transfer to many trips. Passengers hate waiting during transfers.
Automated transit networks (ATN) avoid these conflicts in the following ways.
- Move all stations onto sidings, so through traffic bypasses them at speed.
- Use many small vehicles traveling close together (like cars, not widely-spaced buses).
- Smaller vehicles require smaller infrastructure – that costs less and fits into more places and spaces.
- Use small, interconnected one-way loops spread throughout the community – not just along corridors.
- Small vehicles travel from origin to destination without stopping, traveling on small loops that minimize out-of-the-way travel.
- A network of interconnected loops can be infinitely expanded with no need for transfers.
ATN does not suffer from self-conflicts and can thus provide quick, reliable service throughout the service area with good capacity and low cost.
Capacity
Due to experiences with mass transit systems, some people question the ability of PRT’s podcars to move significant numbers of people. They overlook our dominant transportation option, the automobile, that uses small vehicles to transport most of us, most of the time. So, a better question is: Can PRT deliver satisfactory service using a few guideways spaced roughly 1/2 mile apart? Read how a single guideway can transport as many people as multiple lanes of freeway.
Cost
Mass transit systems have also conditioned people to expect high price tags for building and operating public transit infrastructure. People familiar with the cost of building at-grade Light Rail Transit (LRT) and BART ($60M/mile and $230M/mile respectively) would naturally question the $30M/mile cost of elevated PRT guideways. Likewise, the goal of providing free service is also questioned. Learn why PRT is relatively inexpensive to build and operate.
Hardware
Engineers and gadgeteers are likely more interested in the hardware details of the PRT system proposed for Milpitas.
Videos that introduce PRT concepts and operational systems (in bold).
- 3-minute YouTube video introduction to PRT system (or a version that’s not on YouTube)
- 2-minute review of ATN Systems 1975 to 2023
- Deeper introduction to PRT technology
- 5-minute look at the existing Heathrow Airport (ULTra) PRT system
- 3-minute overview of Autotren (Modutram) PRT system being developed in Mexico
- 15-minute video of Santa Cruz PRT plans and existing systems worldwide
- 17-minute video of 1970’s PRT-like system at Morgantown, West Virginia
- Bubbles & Beams: 4-minute vision of a possible future traffic system, that makes it easy for anyone to travel.
- Glydways: Always Moving (30 seconds)
- 4-minute tourist experience of the Skycube at Suncheon Bay!
- 10-minute intro to Google spin-off Swyft Cities PRT project.
- 30-minute Glydways presentation to Santa Cruz County Regional Transportation Commission (March 7, 2024)
- 2-minute SkyGlyde video of system operational since 2024 in China.
“… changing your mind is one of the best ways of finding out whether or not you still have one.” ― Taylor Mali