Electric Utility Vehicle Control System Architecture

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Utility vehicles, such as lawn and garden tractors and mowers, face challenges in control systems that require improved efficiency and functionality, particularly in transitioning between operational modes and ensuring safe and efficient power management, especially with the rise of electric drive systems which need advanced control architectures to manage traction, auxiliary functions, and safety features.

Innovation Solution

A control system architecture for utility vehicles that integrates a user interface, sensors, and controllers to manage electric transaxles, mower deck operations, and safety features, utilizing a traction controller, auxiliary controller, and communication buses like CAN to regulate power distribution, speed, and direction, enabling programmable functions like panic stop and power management.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If electric drive systems are used in utility vehicles, then fuel efficiency and environmental performance are improved, but control system complexity increases due to the need for advanced power management and mode transitions

Engineering Contradiction:
Improvefuel efficiencyVSAvoidcontrol system complexity
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The control system is divided into multiple independent controllers: a traction controller for managing drive motor operations, an auxiliary controller for PTO and other accessories, and a master controller for coordinating between them. This segmentation allows each controller to specialize in specific functions, managing complexity through modular architecture while maintaining overall system efficiency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A master controller acts as an intermediary between the traction controller and auxiliary controller, coordinating their operations and managing power distribution. This intermediary structure enables centralized power management and mode transition control without requiring direct complex interactions between all system components.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If multiple controllers are used to manage different vehicle functions, then functional versatility and power management capability are improved, but communication overhead and system integration complexity increase

Engineering Contradiction:
Improvefunctional versatilityVSAvoidsystem integration complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The master controller serves multiple functions: it coordinates traction control, manages auxiliary functions, monitors system status, and handles mode transitions. This multi-functionality reduces the need for separate dedicated controllers for each function, thereby reducing communication overhead and integration complexity while maintaining functional versatility.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The master controller combines coordination and monitoring functions that could be distributed across multiple separate controllers. By merging these functions into a single coordinating unit, the system reduces the number of communication interfaces and integration points, simplifying the overall system architecture.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If advanced power management and safety features are integrated, then operational safety and efficiency are improved, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improveoperational safetyVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control system incorporates feedback mechanisms where the master controller continuously monitors system status from both traction and auxiliary controllers, and adjusts power distribution and operational modes accordingly. This feedback-based coordination enables advanced safety features and power management without requiring overly complex hardware architectures.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The master controller performs preliminary coordination and validation of control signals before they are executed by the traction and auxiliary controllers. This preliminary action ensures safety and efficiency requirements are met before operations commence, reducing the need for complex post-execution monitoring and intervention systems.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3109091B1Control systems and methods for electric drive utility vehicles
Publication Date: 2021.11.10 HYDRO GEAR LP
  • EP3109091B1 patent drawingFigure 1
  • EP3109091B1 patent drawingFigure 2
  • EP3109091B1 patent drawingFigure 3

AI summary

The invention provides for a utility vehicle comprising a plurality of vehicle systems comprising an accelerator system providing an accelerator input signal, a traction system, and an auxiliary system; a plurality of operator interfaces for operating the utility vehicle each providing an operator interface input signal; a plurality of sensors each providing a sensor input signal; and an electric motor control system in communication with the plurality of vehicle systems, the plurality of operator interfaces, and the plurality of sensors; the traction system comprising at least one electric drive motor in communication with a driven wheel of the vehicle; the auxiliary system comprising at least one electric auxiliary motor in communication with an auxiliary mechanism; and the electric motor control system comprising: a traction controller in communication with the at least one electric drive motor to facilitate adjustment thereto based on the accelerator input signal and at least one of the sensor input signals; an auxiliary controller in communication with the at least one electric auxiliary motor and the traction controller to facilitate adjustment of the at least one electric auxiliary motor; wherein the traction controller and the auxiliary controller are configured to provide integrated power management and safety control of the at least one electric drive motor and the at least one electric auxiliary motor such that one or more of the at least one electric drive motor and the at least one electric auxiliary motor is automatically adjusted in response to conditions of the vehicle as determined from one or more of the accelerator input signal, at least one of the operator interface input signals, or at least one of the sensor input signals.