Elevator Slide Door Obstacle Detection Using Shifted Light Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sliding door devices face challenges in accurately detecting obstacles due to simultaneous light emission from both light emitters, leading to reduced detection accuracy when light beams are blocked.
Innovation Solution
A sliding door device with first and second light emitters on opposite sides of a doorway, each emitting light beams of different wavelengths, and corresponding imaging means, controlled to turn ON at shifted timings to enhance obstacle detection accuracy by eliminating the effects of reflected light beams.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If both light emitters simultaneously emit light beams to cover the entire doorway area, then the monitored area is fully covered, but the detection accuracy decreases because reflected light from obstacles cannot be properly detected
Solution Approach 1:
The patent applies periodic action by controlling the light emitters to emit light beams in sequence rather than simultaneously. The controller activates the first light emitter, waits for the camera to capture the reflected light, then activates the second light emitter. This periodic emission pattern allows the system to cover the entire doorway area while maintaining detection accuracy, as each camera captures light reflections from obstacles without interference from simultaneous light emissions.
2Productivity
If light emitters emit light beams simultaneously to ensure continuous monitoring, then the monitoring coverage is complete, but obstacles are not detected reliably due to light beam interference
Solution Approach 1:
The patent applies preliminary action by having the controller activate light emitters in a predetermined sequence before capturing images with the cameras. The controller first activates the first light emitter and waits for the camera to capture the reflected light pattern, then activates the second light emitter. This preliminary sequential activation ensures that light reflections from obstacles are captured reliably without interference, maintaining both monitoring continuity and detection reliability.
3Measurement precision
If the light emitters are controlled to emit at shifted timings to improve detection accuracy, then obstacle detection reliability improves, but the system complexity increases
Solution Approach 1:
The patent applies self-service by implementing a control system that automatically manages the sequential activation of light emitters and timing of camera captures without requiring external intervention. The controller internally coordinates the emission timing of light emitters and the imaging timing of cameras, using built-in timers and control logic to ensure proper sequencing. This self-managed approach improves detection accuracy while keeping the added complexity contained within the control system itself.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution improves obstacle detection reliability by covering a wide area and preventing obstacles from being missed, ensuring safe and accurate door operation, including preventing passengers' belongings from getting stuck during opening and reversing door movement if an obstacle is detected during closing.
Implementation Method 1
the light beam reflected by an obstacle is incident on one of the cameras
Implementation Method 2
a pair of cameras, each being for imaging the light-emitting surface of the light emitter opposed thereto
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
In a slide door device in which a first light emitter and first imaging means are provided on a first side of a doorway and a second light emitter and second imaging means are provided on a second side. The first light emitter includes a first light-emitting surface. The second light emitter includes a second light-emitting surface opposing the first light-emitting surface. A controller controls the first and second light emitters and the first and second imaging means to detect an obstacle in vicinity of the doorway, and controls opening and closing of a door according to presence and absence of an obstacle. Further, the controller turns ON the first light emitter and the second light emitter at timings shifted from each other.