Traction Drum Mower Steering via Segmented Drive

Solution Overview

Problem

Existing riderless mowers with traction drums cannot turn without operator-assisted tilting, which damages turf, and autonomous devices lack the ability to rotate like traditional mowers with traction drums.

Innovation Solution

A system with a traction drum and steering member that allows independent rotation of the drive section and lifting of tools using motors, enabling the mower to steer and turn without tilting, and utilizing differential traction drums for precise control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the mower uses a traction drum for propulsion, then weight distribution is improved and turf damage is reduced, but the ability to turn without operator assistance is lost

Engineering Contradiction:

Improveturf damageVSAvoidturning capability

Core Design Contradiction:

Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The mower is divided into a stationary base section containing the traction drum and a rotatable steering section containing the cutting head. This segmentation allows the cutting head to rotate independently for turning operations while the traction drum remains fixed to maintain even weight distribution on the turf.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The steering section is made dynamically rotatable relative to the stationary base section through a steering motor. This dynamic capability enables the mower to turn without tilting, while the stationary traction drum maintains stable weight distribution during both straight-line travel and turning operations.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If the operator tilts the mower to turn, then turning is enabled, but the cutting head damages the turf

Engineering Contradiction:

Improveturning capabilityVSAvoidturf damage

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The mower is divided into a stationary base section containing the traction drum and a rotatable steering section containing the cutting head. This segmentation allows the cutting head to rotate independently for turning operations while the traction drum remains fixed to maintain even weight distribution on the turf.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A steering motor acts as an intermediary mechanism between the control system and the cutting head, enabling rotation of the steering section without requiring physical tilting by an operator. This eliminates the harmful effect of tilting-induced turf damage while maintaining turning capability.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Extent of automation

If autonomous control is implemented, then operator assistance is eliminated, but the ability to rotate like traditional mowers is lost

Engineering Contradiction:

Improveautonomous operationVSAvoidrotation capability

Core Design Contradiction:

Extent of automationVSEase of operation

Solution Approach 1:

The steering section is made dynamically rotatable relative to the stationary base section through a steering motor. This dynamic capability enables the mower to turn without tilting, while the stationary traction drum maintains stable weight distribution during both straight-line travel and turning operations.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The autonomous mower performs its own steering and turning operations through the integrated steering motor and rotatable steering section, eliminating the need for operator assistance. The system serves itself by automatically controlling the rotation of the cutting head relative to the stationary traction drum.

Inventive Principle:

Principle #25Self-service

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

Enables autonomous, damage-free turning and operation of mowers with traction drums, maintaining even weight distribution and minimizing turf damage, while allowing for efficient cutting and clipping collection.

Implementation Method 1

the drive section can be rotated by a steering motor independently of the steering section, thus altering the path of the mobile object

Methodology Applied

Scientific EffectDifferential rotation:

Implementation Method 2

a lifting motor lifts the tool off of the terrain when necessary

Methodology Applied

Scientific EffectMechanical lifting:

Implementation Method 3

by controlling the rates of rotation of the drums, the mobile object may be turned accurately

Methodology Applied

Scientific EffectDifferential traction:

Data Source

PatentUS7853373B2System for steering a traction drum driven mobile object

Publication Date: 2010.12.14 MTD PRODUCTS INC

AI summary

A turf device driven by a traction drum. The traction unit is connected to the tool by an articulable joint which allows the traction unit to rotate horizontally (yaw) and vertically (pitch), as well as roll side-to-side in relation to the tool. The articulation allows the tool and the traction unit to follow undulations in the terrain separately and allows the mobile object to turn by yawing the traction member in relation to the tool.