Franz

The Digital Butler for Elevators

Originally commissioned by the relayr GmbH elevator division (now part of Cedes), Franz is an advanced IoT sensing platform designed to bring intelligence to legacy vertical transportation systems. It serves as a comprehensive “wellbeing monitor,” enabling predictive maintenance for infrastructure that was never designed to be connected.

The Problem: The Legacy “Black Box”

Elevator maintenance companies face a massive technical debt: in mature markets like the EU and North America, over 80% of the installed base consists of elevators that are 20+ years old. These legacy systems are essentially “black boxes,” providing zero real-time data to operators.

This lack of telemetry leads to reactive maintenance and unexpected downtime. In fact, research indicates that 60% to 80% of all elevator service calls and downtimes are caused by door mechanism failures. Even the most experienced technicians struggle to predict when a motor current will spike due to friction or when a door track is nearing failure until the lift is already out of service.

Our Solution: Edge Intelligence for Legacy Lifts

We designed Franz to be the eyes and ears of the elevator cabin. By retrofitting existing cabins with a suite of non-intrusive sensors, we provide the real-time telemetry needed to predict failures before they happen. Franz monitors vibration during travel, travel mileage, door motor temperature, and magnetic fields (to infer motor current), sending aggregated, pre-processed data to the cloud for advanced predictive analytics.

The Engineering: High-Integrity Data in Noisy Environments

Building for elevator shafts presented unique challenges—long distances, high electrical noise, and diverse mechanical configurations.

• Modular Architecture: A centralized main board sits in the cabin, equipped with an accelerometer, barometer, and temperature sensors.
• The LVDS Innovation: To solve the “Long Line Problem,” we used robust LVDS (Low-Voltage Differential Signaling) data links to extend SPI buses to remote sensors (like magnetometers on door motors).
• Cat5 Integration: Our design enables the use of standard, shielded Cat5 cables to connect remote sensors to the main board, maintaining high sampling rates and laboratory-grade signal integrity even in the EMI-heavy environment of a motor room.
• Edge Pre-Processing: High-frequency raw data is sampled and processed at the edge before being fed via USB to a gateway, ensuring only relevant insights are transmitted to the cloud.

Franz transforms a 20-year-old mechanical system into a smart, data-driven asset, drastically reducing emergency callouts and extending the lifespan of critical urban infrastructure.