Presence Sensor Aggregation for Low-Traffic Lighting Buses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lighting systems face challenges with heavy communication bus traffic due to frequent reporting of presence or motion sensor data, which can overwhelm limited communication capacity and jeopardize system operation, especially in support of digital service applications.
Innovation Solution
A sensor module that aggregates presence data within a time grid, using a counter to track occupancy time periods and communicates this data to a remote controller on a regular basis or upon request, reducing the frequency of reports and allowing for a slower, cost-efficient bus system like DALI.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If presence or motion sensors frequently report occupancy data to the remote controller, then digital service applications can be supported, but communication bus traffic becomes heavy and may overwhelm the limited communication capacity
Solution Approach 1:
The sensor module performs preliminary aggregation of occupancy data locally before transmission. The processing means aggregate unit time periods in which presence is detected, and only then submit the aggregated data to the remote controller. This preliminary processing at the sensor module reduces the volume of data that needs to be transmitted over the communication bus.
Solution Approach 2:
The sensor module acts as an intermediary between the occupancy sensing function and the remote controller. It aggregates multiple occupancy detections into consolidated data packets, mediating between the need for detailed occupancy information and the limited communication capacity of the bus system.
2Loss of information
If multiple sensors continuously report presence data to the remote controller, then accurate occupancy information is available, but communication bus capacity is exceeded
Solution Approach 1:
The sensor module aggregates occupancy data from multiple sensors and time periods before transmission. This preliminary aggregation ensures that occupancy information is consolidated and accurate, while reducing the frequency and volume of communications to maintain system reliability.
Solution Approach 2:
Instead of continuous reporting, the system uses periodic aggregation where the sensor module submits aggregated occupancy data at regular intervals or upon request. This periodic communication pattern maintains information accuracy while preventing communication bus overload.
3Loss of information
If sensors report every detection event, then complete occupancy data is captured, but communication traffic increases system complexity and energy consumption
Solution Approach 1:
The processing means aggregate multiple occupancy detection events into consolidated time period data before transmission. This preliminary consolidation maintains complete occupancy information while simplifying the communication protocol and reducing overall system complexity.
Solution Approach 2:
Multiple individual occupancy detection events are merged into aggregated time period data. This combining approach preserves the completeness of occupancy information while reducing communication overhead and simplifying data handling protocols.
Data Source
Figure 1
Figure 2
AI summary
A sensor module (1) for a lighting system (3) is provided, comprising sensing means (101) and processing means (103). The sensing means (101) are configured to sense a presence of a person within a sensing zone (102) at a time instant. The time instant falls within a corresponding unit time period of a time grid. The processing means (103) is configured to aggregate those of the plurality of unit time periods in which the sensing means (101) senses the presence of the person. This may reduce an amount of traffic reported by presence or motion sensors of a lighting system in support of new digital service applications, and may further allow for a deployment of a slow but cost-efficient and energy-saving bus system such as a DALI or a KNX interface.