Introduction

This is the first in a series of posts on an Autonomous Compact Factory (ACF). This idea arose from the authors need to consolidate an advanced engineering workshop into a form factor that is extremely compact, portable and suitable to fit aboard a sailboat. Other use cases include rapid deployment into disaster zones, for military usage within vehicles, as an air portable capability and even for deployment to other planets to support humans in space.

Concept

The autonomous compact factory should have additive and reductive manufacturing capability, support direct human and autonomous operation, be lightweight and energy efficient and support auto material loading, self cleaning and tool / material change.

Functional Requirements

  • All modules to fit within a 500mm cube space claim
  • No module to exceed 50 kg in transport mode. Total factory weight not to exceed 100 kg.
  • Work volume to not be less than 400mm cube. Work chamber to support inert gas volumes and positive pressure.
  • Have reductive functionality of a lathe, mill, EDM and surface grinder. Material limits tbd.
  • Have additive functionality of TIG welder, Laser welder, 3D printer and composite resin injection
  • Robot arm with 3 9 DOF joints. Can be used for tool replacement, polishing, welding, laser, composites fluids and loading and unloading material
  • Self load and unload material from the work chamber
  • Self cleaning
  • Remote and direct operation
  • Autonomous and unattended operation

Non Functional Requirements

  • Operate from off grid power sources
  • Have form factor to fit within vehicles, boats, aircraft and space capsules
  • Be module and can be carried by one person
  • Have self healing, self cleaning and self calibrating capabilities
  • Minimise use of consumables and special tooling
  • Have adaptive vibration and noise control for operation on a normal table or floor

Design Criteria

The Autonomous Compact Factory is simple in that it is a single work center that performs multiple roles but unusually complex in that it supports a multitude of additive and reductive operations. The following unique design to criteria will be explored further using modelling and simulation techniques.

Noise, Vibration and Inertia

Traditional machine tools use mass damping for stability and to support high tolerances. The Autonomous Compact Factory cannot use mass damping and will experience undesirable inertial forces. This necessitates the use of active damping.

Tooling, Wear and Tool Changing

It is not feasible to include a typical complete set of tooling for the ACF. Therefore a limited set of cutters, abrasives and form factors will be used. Very high speed ( > 10,000 rpm) and small tooling (3 - 5mm diameter) will be needed.

Continue reading articles in my Mechanical Engineering series