Pool Cleaner Speed Control for Path Accuracy

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Swimming pool cleaning devices often experience deviations from their intended path direction due to abrupt braking or impact with pool walls, leading to cumulative position errors, especially in larger pools, and existing sensors, particularly mechanical ones, fail to provide reliable control for maintaining stable cleaning paths.

Innovation Solution

A method where the cleaning device operates at low speed when approaching a pool wall, reducing position errors by controlling the distance and speed, and using differential motor speed control to guide the device into offset or parallel cleaning paths, allowing for controlled stopping and efficient cleaning patterns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the cleaning device travels at high speed along cleaning paths, then cleaning productivity is improved, but position accuracy deteriorates due to cumulative errors from abrupt braking or impact with pool walls

Engineering Contradiction:
Improvecleaning speedVSAvoidpath direction accuracy
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The cleaning device dynamically adjusts its speed based on the cleaning path phase. It travels at high speed along central cleaning paths to maximize productivity, but automatically reduces speed to low speed when approaching pool walls or obstacles. This dynamic speed adjustment resolves the contradiction by allowing high speed where safe and low speed where precision is needed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The control device continuously monitors the cleaning device's position and speed, using feedback from sensors to detect when the device is approaching a pool wall or obstacle. Based on this feedback, the control device adjusts the motor speeds to reduce the device's speed before impact, preventing cumulative position errors while maintaining high speed during open water cleaning.

Inventive Principle:
Principle #23Feedback

2Reliability

If mechanical contact means are used to detect pool walls, then reliability is improved, but device complexity increases and response time is insufficient for abrupt stopping

Engineering Contradiction:
Improvedetection reliabilityVSAvoidsensor system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control device performs preliminary action by reducing the cleaning device's speed in advance before it reaches the pool wall or obstacle. Instead of waiting for mechanical contact to trigger a response, the system proactively lowers speed based on predicted proximity to walls, providing sufficient reaction time for smooth stopping without complex sensor systems.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The cleaning device uses its own motor control system to detect and respond to pool wall proximity. The control device monitors cleaning path progress and automatically adjusts motor speeds to prevent impact, making the system self-regulating without requiring external complex sensor systems or additional mechanical contact means.

Inventive Principle:
Principle #25Self-service

3Stability of the object's composition

If the cleaning device reduces speed when approaching pool walls, then path stability is improved, but cleaning time increases

Engineering Contradiction:
Improvecleaning path stabilityVSAvoidcleaning time
Core Design Contradiction:
Stability of the object's compositionVSLoss of time

Solution Approach 1:

The cleaning path is segmented into different phases: high-speed cleaning phase in open water and low-speed approach phase near pool walls. The control device manages each phase separately, maintaining high speed during stable cleaning sections and reducing speed only briefly during wall approaches. This segmentation allows the system to optimize for both speed and stability without sacrificing overall cleaning efficiency.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP1826338B1Working method and cleaning device for cleaning a swimming pool
Publication Date: 2011.11.16 3S SYSTTECHN AG
  • EP1826338B1 patent drawingFigure 1
  • EP1826338B1 patent drawingFigure 2

AI summary

The method involves driving a cleaning device (2) in a passage in a cleaning path (4) from an initial position in a forward direction to an excavation position in a swimming pool wall (3) at a low speed. A covered distance in the path is measured, and the device is guided into another passage in another cleaning path (5) at low speed. The device is guided in the path (5) at high speed up to a covered distance that is smaller than the former distance. The device is again driven in the path (5) until the wall is excavated. An independent claim is also included for a cleaning device with a control device.