Lift Arm Orientation Control for Loaders

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Operators of power machines, such as loaders, face challenges in precisely controlling the position and orientation of work implements relative to gravity, leading to material spillage during lifting and lowering operations, especially on uneven terrain.

Innovation Solution

A system and method that control lift arm and tilt actuators using an enabling input device, lift arm control input, and tilt control input, with a controller managing power source signals to move the lift arm to a target position and maintain the implement carrier at a consistent orientation relative to gravity, incorporating sensors for position and orientation feedback.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the lift arm path is not perfectly vertical, then raising or lowering the lift arm changes the orientation of the implement with respect to gravity, but this causes material to spill out during the raising or lowering process

Engineering Contradiction:
Improveimplement orientation controlVSAvoidmaterial spillage
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The system uses an orientation sensor to detect the implement's angle relative to gravity and provides feedback to the controller. The controller automatically adjusts the tilt actuator to maintain the desired orientation, creating a closed-loop control system that prevents material spillage during lift arm movement.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The tilt actuator serves as an intermediary mechanism between the lift arm movement and the implement orientation. By independently controlling the tilt degree, it mediates the relationship between vertical lift motion and horizontal material stability, allowing the implement to remain level even as the lift arm follows a non-vertical path.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If the power machine travels over uneven terrain, then the relationship between the implement and gravity changes, but this makes it difficult to maintain consistent implement orientation

Engineering Contradiction:
Improveterrain adaptabilityVSAvoidimplement orientation stability
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The orientation sensor continuously monitors the implement's angle relative to gravity regardless of terrain conditions. The controller receives this feedback and automatically compensates for terrain-induced orientation changes by adjusting the tilt actuator, maintaining stable implement orientation even when traveling over uneven ground.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system uses the orientation sensor to automatically detect and correct its own orientation deviations caused by uneven terrain. The controller and tilt actuator work together in a self-regulating manner to maintain the desired implement orientation without requiring external intervention or manual adjustment by the operator.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If repetitive positioning of the implement is required for digging and loading operations, then the operator must repeatedly concentrate on precisely controlling the lift arm, but this reduces operational efficiency

Engineering Contradiction:
Improveimplement positioning precisionVSAvoidoperational efficiency
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The system uses sensors to detect the lift arm position and implement orientation, providing continuous feedback to the controller. The controller automatically adjusts the actuators to achieve and maintain the desired implement position, eliminating the need for repetitive manual concentration and improving operational efficiency while maintaining precision.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The controller acts as an intermediary that translates the operator's high-level positioning commands into precise actuator control signals. It mediates between the operator's intent and the actual implement position, automatically handling the repetitive adjustments needed for precise digging and loading operations.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3289142B1System and method for positioning a lift arm on a power machine
Publication Date: 2023.04.05 DOOSAN BOBCAT NORTH AMERICA INC
  • EP3289142B1 patent drawingFigure 1
  • EP3289142B1 patent drawingFigure 2
  • EP3289142B1 patent drawingFigure 3

AI summary

A method of controlling a lift arm actuator (114; 314) and a tilt actuator (124; 324) to control positioning of an implement carrier (130; 330) coupled to a lift arm (120; 320) of a power machine (100; 300). An activation signal is received from an enabling input device (166; 370). A lift arm control signal is received from a lift arm control input (162; 362) commanding movement of the lift arm. The lift arm actuator is controlled responsive to receipt of both of the activation signal and the lift arm control signal to move the lift arm to a target lift arm position and to move the implement carrier to or maintain the implement carrier at a target implement carrier orientation relative to a gravitational direction.