Sevensense Stories: Schindler
How Schindler is innovating the installation of elevators with 3D Digital Twins
The Schindler Group is an international leader in the manufacturing of elevators, escalators, and moving walks for all types of buildings. It carries more than one and a half billion people each day in buildings, such as residences, offices, or commercial premises and builds tens of thousands of elevators all around the world, each year. The company is headquartered in Ebikon, Switzerland, but it is present in over 140 countries worldwide.
Sevensense is supporting Schindler with the creation of a device for automated scanning and mapping of an elevator shaft. Working side by side, the device Sense-I has been successfully developed and is being used by selected customers.
Before an elevator is installed, each shaft is measured by a technician using plumb lines, double meters, and laser measuring devices. In most cases, this takes place outside of the elevator shaft, as there is usually no scaffolding inside the shaft yet. This process ensures that the shaft and all door openings fulfill the tolerance ranges for the installation. The required measurements are time-consuming and can only be taken at openings in the shaft. It is therefore not possible to verify whether the shaft width is within the tolerance range in between floors. As a result, such problems are only detected during the installation of the elevator. Consequently, rail spacers have to be ordered, which eventually delays the installation and increases costs. Overall it can be said that today's measurement method is incomplete, time-consuming, and error-prone.
Traditional 3D scanners are very well proven in the construction industry to measure buildings and construction sites. However, in most cases, these are stationary, so they can only measure a fraction of a large shaft at once. The mobile solutions are usually relatively expensive and do not produce exact models for the low-structure and self-similar elevator shaft environment. In contrast, the Visual SLAM technology of Sevensense, which accurately measures the environment using multiple cameras and motion sensors, has proven to overcome those limitations and produce reliable results.
Together with Sevensense, Schindler developed the Sense-I measuring device, which automatically generates a complete and very accurate 3D digital twin of an elevator shaft.
Together with Sevensense, Schindler developed the Sense-I measuring device, which automatically generates a complete and very accurate 3D digital twin of an elevator shaft. Sense-I is equipped with our solution: Alphasense Position. This versatile solution can be adapted to fit different requirements, as for this case, the Alphasense Position unit is equipped with four cameras that are aligned horizontally and provide images of all four shaft walls.
The Sense-I device can be operated by pulling it across the entire height of the shaft via a pulley in the shaft head to record images and motion data. Afterward, the Sevensense mapping algorithm transforms the recorded information into a 3D model/digital twin of the shaft. The technician can then compare the reconstructed 3D model of the shaft with the originally planned design. Positions at which the shaft dimensions are not fulfilling the permissible tolerance range are thus identified early on in the elevator installation process and can be communicated to the acceptance technician.
Schindler's goal is to automate everything from inspection to installation. Eventually, they are aiming to use the Sense-I to inspect a shaft, place rails automatically in the CAD model of the building, and then let a specialized robot equip the whole elevator shaft with rails.
Currently, the Sense-I is being used by selected customers of Schindler, involved in the commissioning of high-rise buildings. The device, equipped with Alphasense Position, brings down the inspection time for elevator shafts from multiple days, for installing the plumb lines and measuring the shaft on every floor, to a maximum of one day, even for large multi-shaft elevators. Moreover, it makes it safer than conventional methods and enables additional insights into the condition of the shaft.
As an overall result, this innovation not only demonstrated to save time and costs for Schindler and its customers, but also proved the versatility and precision performance of Sevensense’s Visual-SLAM technology.
Read more about our cooperation with Schindler in the article by Studer, Bitzi and Zimmerli, “Intelligent 3-D Elevator Shaft Mapping”, CTBUH Journal, 2021 Issue 1.