Case study – Transportation
Platform Screen Door Live Monitoring System (LMS)
Gilgen Door Systems (GDS) is a Swiss manufacturer of high-performance automatic doors, with a strong specialisation in Platform Screen Doors (PSDs) for metro stations and rail networks across Europe and Asia-Pacific. PSDs are safety-critical systems – operated continuously, around the clock – and a single malfunctioning door unit can potentially disrupt train services. Until this engagement, GDS's maintenance regime covered preventive maintenance (with scheduled intervals) and reactive maintenance (after an actual failure). Field engineers received alarm notifications but had no remote visibility into door health: diagnosing a fault meant travelling to the station, physically connecting to the PLC, downloading log files, and interpreting raw error codes. With dozens of doors per station and installations spread across multiple metro networks, this approach is labour intensive and presents a lack of failure prediction capability. 56k.Cloud partnered with GDS to design and deliver a cloud-native Live Monitoring System (LMS): a purpose-built IoT platform that bridges the gap between the physical door controllers and a centralised, real-time operations dashboard. The system connects every PSD controller in the network through an industrial edge gateway to the cloud, enabling GDS and metro operators to monitor, diagnose, and respond to door events from anywhere in the world without setting foot on the platform.
The problem
Gilgen Door Systems faced a set of deeply interconnected operational and technical challenges. Door controllers (PLCs) and their associated field bus networks operated in isolated station environments, completely disconnected from any cloud or internet infrastructure. There was no mechanism for GDS or the metro operator to observe door status in real time. When a fault alarm was triggered, the only recourse was to dispatch a technician to the site. Retrieving fault logs involved a physical FTP connection to the PLC, a process that could take hours, particularly at stations in geographically dispersed metro networks. Each station was an island. There was no aggregated view of the door fleet, making it impossible to identify systemic patterns, compare station health, or prioritize maintenance resources based on real risk. GDS's installations were growing across multiple operators and regions. A maintenance model that required on-site presence for every diagnostic event could not scale alongside the business. Metro operators increasingly require detailed audit trails and uptime reporting for safety-critical systems. Manual log collection was insufficient to meet these evolving compliance obligations. To address these challenges, GDS sought a cloud-based IoT platform with edge computing capabilities, one that could connect to the existing field infrastructure without replacing it, and that would form the foundation for a data-driven, proactive maintenance strategy.
- No remote fault visibility
- Manual, time-consuming diagnostics
- Fragmented data, no fleet-level insight
- Scalability constraints
- Regulatory and audit pressure
The solution
56k.Cloud designed and delivered a full-stack IoT solution, spanning hardware selection, edge software development, cloud infrastructure, and a web-based operator dashboard. The architecture was built with three guiding principles: non-invasive integration (no changes to existing field hardware or PLC software), security by design (hardware-rooted device identity and least-privilege cloud access), and SaaS replicability (the platform can be onboarded to new operators without re-architecting the core system). An industrial-grade IoT edge gateway is deployed in the equipment room of each metro station. The device bridges two worlds: on one side, it connects to the station's local OT network, communicating with the door PLCs via OPC-UA – the standard industrial interoperability protocol – and receiving structured fault log and movement profile files via FTP. On the other side, it maintains a secure, authenticated uplink to the cloud over 4G LTE, with a hardware-backed device certificate providing a unique, tamper-resistant identity for each gateway. The gateway runs a combination of industrial IoT middleware (for fieldbus communication) and a cloud-managed edge compute runtime, backed by the cybersecurity features outlined above. Three custom software components run continuously on the device: a heartbeat and telemetry component that polls door operational data from the PLCs at regular intervals (door state, locking time, motor parameters, cycle counters) and publishes it to the cloud in real time via a lightweight messaging protocol; a fault log component that detects and retrieves structured fault event log files from the PLCs on a scheduled basis and uploads them to cloud object storage, with local buffering to handle up to 48 hours of connectivity loss without data loss; and a profile log component that retrieves full door movement profile data (the motor current curve for each door cycle) and stores it in the cloud for trend analysis and early anomaly detection. All edge software components are deployed and updated over the air from the cloud, meaning zero on-site visits are needed for software maintenance. The cloud backend is built on a multi-account, governed cloud infrastructure, with separate environments for development, staging, and production. A landing zone framework enforces security baselines, centralised audit logging, and cross-account access controls across all environments. Incoming telemetry from the gateways is received by a cloud IoT connectivity service, which authenticates each device and routes messages through a rules engine. From there, data flows into distinct processing paths: an industrial time-series data store, cloud object storage, a managed NoSQL database, and serverless compute functions.
The dashboard
The operator-facing interface is a web application providing a multi-level view of the entire door fleet. It is delivered as a cloud-hosted web application accessible to authorised users from any device, with role-based access control and JWT-secured API calls. Real-time analytics results are pushed to the browser via a persistent WebSocket connection, eliminating the need for polling.
- Network map: geographical or schematic overview of all stations; colour-coded health status; alert counts per station.
- Station view: per-station gateway and PLC connectivity status; platform selector; live alarm list.
- Door grid: visual grid of all doors on a platform (up to 40+ per station); per-door status with fault indicators.
- Alerts: real-time alarm feed – obstacle detection, power faults, multiple door failures, with severity classification.
- Parameter analytics: time-series charts for mechanical parameters; configurable warning and critical threshold overlays; historical comparison across doors and dates.
The outcome
The deployment of the LMS across the initial fleet (16 stations and over 640 individual door devices) delivered measurable operational and business results.
Key metrics: 16 stations monitored · 640+ doors under management · 16 edge gateway devices deployed · OTA fleet software updates
- Continuous remote monitoring of every connected door, 24/7, across all stations simultaneously from a single dashboard, without any on-site presence required.
- Sub-minute fault alerting: when a door triggers an alarm, the event is visible on the dashboard and dispatched to the responsible maintenance team within seconds, rather than discovered hours later during a manual check.
- Remote diagnostics: fault logs and operational data are available instantly via the dashboard, allowing engineers to diagnose the root cause of an issue and arrive on site with the correct spare parts and tools, eliminating exploratory visits.
- Early anomaly detection: trending of door mechanical parameters (motor current profiles, locking times, cycle counts) enables identification of doors that are degrading before they fail – enabling planned intervention rather than emergency response.
- Reduction in physical interventions: the ability to triage and diagnose remotely means a significant proportion of alarm-triggered site visits are eliminated or consolidated into planned maintenance windows.
- Improved equipment availability: faster fault response and proactive maintenance scheduling directly reduce door downtime and improve service reliability for the metro operator.
- Compliance and auditability: all door events, fault logs, and parameter history are stored and queryable, providing the detailed audit trail required by metro operators and safety regulators.
- Scalable operations: the same engineering team can now manage a significantly larger door fleet without a proportional increase in headcount. More doors are served per technician.
- SaaS replication: the platform architecture is designed to be onboarded to additional metro operators and regions without fundamental re-engineering. Each new operator deployment inherits the same security baseline, monitoring capabilities, and operational tooling.
It runs in production today. Built with Gilgen's team, owned by Gilgen, and operated by us.