Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - S-CODE (Switch and Crossing Optimal Design and Evaluation)

Teaser

Track switches are a fundamental element of any rail network which has multiple routes. Without them it would not be possible to safely guide trains from one route to another. However, they also limit the capacity and overall reliability of the network because of the potential...

Summary

Track switches are a fundamental element of any rail network which has multiple routes. Without them it would not be possible to safely guide trains from one route to another. However, they also limit the capacity and overall reliability of the network because of the potential impact of faults in the track-switch and the system’s safety critical nature. Since the inception of railway track switches, almost two centuries ago, very little has changed in terms of their basic layout and operation apart from the introduction of point machines. In contrast, industries such as aerospace, automotive and manufacturing have made radical improvements to their products and processes through the introduction of advanced materials and new designs incorporating mechatronics technologies.

The challenge for the S-CODE project is to emulate some of the achievements and advances in other sectors in order to develop improved solutions for railway switches and crossings. Hence, the overall aim of S-CODE is to investigate, develop, validate and initially integrate radically new concepts for S&C that have the potential to lead to increases in capacity, reliability and safety while reducing investment and operating costs. The project will identify radically different technology concepts that can be integrated together to achieve significantly improved performance for S&C based around new operating concepts (e.g. super-fast switching, self-healing switches).

The key outcomes and innovations of the S-CODE project will be:
• The development and prototyping of a modular whole system switch and crossing architecture that allows subsystems to be changed over the life of the S&C. This will enable innovations to be added as they become available. The architecture and subsystems will be modelled to allow rapid development of further capabilities.
• The design and prototyping of Next Generation Design components that can be incorporated into the architecture, using new materials and technologies to create a variety of permanent way subsystems.
• The design and prototyping of a Next Generation Control subsystem that can be incorporated into the architecture, which will include an ‘immune system’ capable of self- adjustment, self-correction, self-repair and self-healing.
• The design and prototyping of a Next Generation Kinematic subsystem that can be incorporated into the architecture, that includes new actuation and locking philosophies that make use of concepts such as redundancy and ‘limp-home’ through the use of novel actuators and mechatronic systems.
Analysis will be undertaken to quantify the value of these innovations from the perspective of reliability, life-cycle costs and higher speed switches/train throughput.

Work performed

There are three phases to the S-CODE programme:

Phase 1: Requirements and initial design
Phase 2: Technical concept development
Phase 3: Demonstration and evaluation

Phase 1 of the project, which was complete at the end of the first reporting period, focused initially on understanding the top level functional requirements for a track switch system. Then literature reviews were combined with horizon scanning in order to identify best-practice and potential innovative technologies from beyond the rail industry. Bringing these together through divergent thinking design workshops allowed over one hundred radical high-level design ideas to be generated. From this set it was then possible to systematically down select to a manageable set of twenty two designs. These were then combined to provide five high-level layout concepts for analysis in Phase 2. The technology concepts are being developed and integrated into the five new switch concepts. This is being done through a combination of detailed design, computer modelling in CAD, multi-body dynamics, simulation and visualisation. The output of this exercise will be a suite of technologies for control, health monitoring, new use of materials and components, and novel kinematic systems and mechatronic actuation systems, which can be combined in a variety of ways. Following this plug-and-play tool-box approach the project aims to generate a range of technologies, which can be used individually to improve the performance of current S&C, and can be brought together in order to provide radically transformed switches in the future.
Some of the main elements currently in development include:
• Plug and play modular architecture that will allow different components and subsystems to be replaced, renewed and updated over different time-frames.
• Next generation control - using embedded electronics, control and sensors to re-imagine the control, monitoring, inspection and safety approach and thereby improve reliability and reduce life cycle costs.
• Next generation components will use novel materials and design to enable the switching and locking function to be radically changed, to improve the wheel/rail interaction, and to reduce the need for complex inspection and maintenance.
• Radical kinematic systems which will harness the power of mechatronic systems and fault tolerant design to yield improved actuation in terms of reduced switching time, improved reliability and availability.
Phase 3 of the project will focus firstly on the evaluation and validation of the technologies proposed. Initially, the concepts will be validated individually through both laboratory testing and simulation. Then these modular technology elements will be integrated to produce candidate solutions for development at higher technology readiness levels. The impact of the S-CODE research outputs will be assessed by the partners and stakeholders using methods for the assessment in terms of RAMS, LCC and capacity, and other criteria which are currently being identified.

Final results

In terms of impact on the railways and progress beyond the state of the art, the S-CODE project team are working toward a set of top-level targets that indicate their ambition for future switch and crossing technology:

• 100% increase in capacity
This will be achieved by a range of measures which include: firstly, a decrease in the time needed for switching and locking, which reduces the headway allowance; secondly, seeking to increase the travel speeds through S&C; and finally, significantly improving the reliability, availability and maintenance of the switch system.
• 30% reduction in the life cycle costs and increased safety
The design efforts are focused toward simplicity, with built-in fault tolerance, health monitoring and modular architecture throughout the system. This will significantly reduce maintenance costs as the system moves to condition based maintenance, and will see dramatic improvements in reliability (target 50%) and availability (target 100%). The modular nature will make installation, upgrade and improvement far simpler processes than at present.
• 50% increase in reliability and punctuality
This will be addressed through fault tolerant systems and maintenance free design, combined with the development of innovations in the area of health monitoring that will ultimately lead to an S&C immune system for self-healing. Concomitant with this, our research aims to reduce wear and tear around S&C by suggesting improvements to the infrastructure and, in some cases, the vehicles in order to optimise the wheel/rail interface.

Website & more info

More info: http://www.s-code.info.