Design of a 7 HP Diesel Engine Mini Tractor (Large Power Weeder Concept)

Project Overview

We want to create a complete mechanical design for a mini tractor utilizing a 7 HP diesel engine. The project deliverables will include conceptual sketches, 3D CAD models, engineering drawings, bill of materials (BOM), and detailed instructions for fabrication.

Key Objectives:

Design a sturdy yet compact frame to house the 7 HP engine, transmission, and differential.

Provide multiple forward gears, reverse gear, and PTO capabilities.

Ensure maneuverability in small farmland or narrow pathways.

Incorporate safety elements and easy maintenance features.

Scope of Work & Deliverables

Phase 1: Requirement Analysis & Conceptual Design

Requirements Gathering

Discuss and finalize key requirements:

Overall dimensions, power transmission layout, PTO requirements, safety standards, etc.

Outline constraints (budget, available fabrication methods, etc.).

Conceptual Sketches

Hand-drawn or simple digital sketches illustrating the overall layout (engine, gearbox, differential, steering, seating, etc.).

Provide multiple concept options, if possible (e.g., chain drive vs. belt drive, handlebar steering vs. steering wheel).

Deliverables (Milestone 1)

A short Requirements Specification Document (PDF/Word).

Conceptual Drawings (PDF/PNG) showing at least two design options.

A brief Feasibility Analysis (pros/cons of each concept).

Phase 2: Detailed 3D CAD Model

Preliminary 3D Modeling

Create the main assembly in 3D CAD software (SolidWorks, Fusion 360, or similar).

Include major components: engine block placeholder, gearbox, clutch (if applicable), differential, chassis frame, wheels.

Refinement of Layout

Check for clearances, ergonomics (operator seat position), and weight distribution.

Make adjustments based on feedback.

Deliverables (Milestone 2)

3D CAD Assembly File (native format) with all major components.

Exploded View Renderings (JPG/PNG/PDF) of the assembly from various angles.

A short Design Progress Report highlighting any open questions or issues.

Phase 3: Engineering Analysis & Finalization

Mechanical Calculations & Stress Analysis

Perform basic load/stress calculations on critical parts (e.g., frame, axles).

Ensure the design can handle typical field conditions (shocks, vibrations).

Gear Ratios & Transmission Details

Determine appropriate gear ratios to leverage the 7 HP engine effectively.

Check and validate clutch or direct coupling parameters.

Specify chain/belt drive types, sprocket sizes, or pulley sizes.

PTO Integration

Finalize the PTO drive details (speed, torque, output positioning).

Design Revisions

Revise the 3D model based on analysis outcomes.

Update the design to address any identified weak points or conflicts.

Deliverables (Milestone 3)

Updated 3D Model with all revisions.

Stress/Load Analysis Report (could be a short PDF with FEA results or hand calculations).

Transmission & Gear Ratio Report with justification.

PTO Integration Details (if applicable).

Phase 4: Detailed Manufacturing Drawings & BOM

2D Technical Drawings

Generate dimensioned drawings for fabrication (frame layout, gearbox mounting, wheel hubs, bracket details, etc.).

Include welding details, tolerances, material specifications.

Bill of Materials (BOM)

Create a consolidated list of materials, standard parts, fasteners, bearings, etc.

Provide potential vendor/supplier references (if known).

Assembly Instructions

Outline step-by-step assembly instructions (text + diagrams/screenshots).

Include notes on safety, best practices, and recommended tools.

Deliverables (Milestone 4)

Detailed 2D Fabrication Drawings (PDF + native CAD format).

Complete BOM (Excel or CSV) with part numbers, material specs, approximate costs.

Assembly & Fabrication Guide (PDF/Word) with visuals.

Automotive Engineering CAD / CAM Mekanisk Ingeniørarbejde Solidworks Product Development

Projekt ID: #39014174

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