Vision-guided suction grabber for autonomous fruit picking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current automatic fruit picking machines have low picking rates and cause significant damage to fruits due to complex and time-consuming coordinate transformations in their vision systems, leading to inefficiencies and inaccuracies.

Innovation Solution

A fruit picking device equipped with a robot arm and a vision system where spatial coordinates from the vision system are directly used to steer a suction grabber, eliminating the need for complex coordinate transformations, combined with a funnel-like suction cup and pneumatic system for gentle fruit handling, and a picking hand with a camera and suction cup aligned for efficient fruit identification and picking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If complex coordinate transformation is used in the vision system, then the vision system can provide accurate fruit position data, but the calculation time increases significantly reducing picking speed

Engineering Contradiction:
Improvefruit position accuracyVSAvoidpicking speed
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent extracts and eliminates the complex coordinate transformation step from the vision system pipeline. By directly using the vision system coordinates to steer the suction grabber without transformation, the calculation time is significantly reduced while maintaining picking accuracy, thus resolving the contradiction between measurement precision and productivity.

Inventive Principle:
Principle #2Taking out (Extraction)

2Device complexity

If traditional mechanical grippers are used for fruit picking, then the picking mechanism is simple, but the fruit is likely to be damaged during handling

Engineering Contradiction:
Improvepicking mechanism simplicityVSAvoidfruit damage
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the traditional mechanical gripper with a suction-based grabbing mechanism. The suction grabber uses negative pressure to hold the fruit, eliminating the need for complex mechanical fingers and joints. This substitution reduces device complexity while significantly reducing fruit damage, as the suction method provides gentle, uniform contact pressure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs pneumatic principles through the suction grabber system, using vacuum pressure to grasp and hold the fruit. This pneumatic approach replaces complex mechanical gripping mechanisms with a simpler pressure-based system that is gentler on the fruit surface, thereby reducing damage while maintaining picking effectiveness.

Inventive Principle:
Principle #29Pneumatics and hydraulics

3Adaptability or versatility

If the camera is not aligned with the suction cup, then the picking hand design is more flexible, but complex coordinate transformation is required reducing time efficiency

Engineering Contradiction:
Improvepicking hand design flexibilityVSAvoidcoordinate transformation time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent merges the camera and suction cup into a aligned configuration within the picking hand assembly. By positioning the camera such that its optical axis is collinear with the suction cup's central axis, the system eliminates the need for complex coordinate transformations between the two components. This merging of functional elements maintains design flexibility while significantly reducing calculation time for fruit positioning and grabber steering.

Inventive Principle:
Principle #5Merging (Combining)

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 significantly enhances the time-efficiency and accuracy of fruit picking, reducing fruit damage and increasing the picking capacity, with over 80% of apples detected and harvested without major bruising or damage in field experiments.

Implementation Method 1

The suction grabber comprises a funnel-like suction cup allowing partial enclosure of a fruit and means for generating an internal vacuum upon enclosure of a fruit in said cup

Methodology Applied
Scientific EffectVacuum: Vacuum

Data Source

PatentEP2086308B1Autonomous fruit picking machine
Publication Date: 2011.01.19 KATHOLIEKE UNIV LEUVEN
  • EP2086308B1 patent drawingFigure 1
  • EP2086308B1 patent drawingFigure 2A~2B
  • EP2086308B1 patent drawingFigure 3~4

AI summary

In a first object the present invention provides a fruit picking device which comprises a robot arm carrying a suction grabber and a vision system for the identification of a fruit and the determination of the position of said fruit relative to the suction grabber. The vision system of the device of the present invention is arranged such that the spatial co-ordinates of a fruit as provided by said vision system can be readily used to steer the suction grabber towards the fruit, without the need for complex transformation of the vision system co-ordinates into robot co-ordinates. This set-up of the vision system allows limiting the calculation time required for carrying out a picking cycle, which significantly enhances the time-efficiency of this automatic fruit by fruit picking device.