3D Virtual Models
Introduction
In recent years, modern engineering design and manufacture has benefited from the introduction of affordable yet powerful 3D, solid modelling, computer-aided design software. I have the opportunity of using this ‘high-end’ 3D design software to enhance our gauge 1 hobby.
BR 9F Loco: Screen shot.
All the gauge one and 16mm locomotives modelled in 3D are successful, proven designs and most builders will have little difficulty with the component drawings. However, there are new hobbyists without any sort of engineering background. They most definitely appreciate the enhanced details provided by a fully viewable 3D virtual model.
The process was originally applied to the 'PROJECT', which is the intellectual property of G1MRA and was well received by all who use it as a valuable reference. The virtual model of 'DEE', another G1MRA model, is also provided as a CD ROM.
The 3D model provides a comprehensive study of the designs as a virtual model including all parts and assemblies. More and more models are being added as the designers appreciate the benefits afforded to those who wish to build their pride and joy.
The 3D Viewer: eDrawings®
At the heart of this virtual model study, is a powerful and fully featured 3D viewer provided royalty free for use with the CAD software. The model was created with Solidworks® .The data is in the form of eDrawing® which can be viewed on your personal computers assuming it has a minimum specification. A media viewer must be installed to see the supporting materials such as photographs and video.
The 3D viewer enables the virtual model to be rotated and studied from every conceivable angle. The viewer is embedded within the eDrawing£reg; and is loaded almost instantly whenever the particular model image is loaded.
The visual effect of the 3D viewer is awesome and the user is left to ponder 'how do they do that?' This form of subject presentation produced a storm of positive comments when it first came to industry. I know it took me by surprise when I first saw it. Victor Meldrew would say 'I don’t believe it!' and I must say that I think it is a quantum leap in terms of quality technical illustration capabilities, which will leave many people absolutely astounded.
There are many powerful features in the 3D viewer, almost too numerous to list here.
The visualisation
- On the companion 3D CD ROM, the components and assemblies are fully coloured to offer a general representation of the materials used in construction in full 3D visual form. The effect is similar to the hand-drawn and coloured general arrangement drawings of the Victorian era, but infinitely better.
- Each model floats in the graphics window as it is automatically animated between each of the main view orientations: front, back, RH side, LH side, top, bottom and an isometric view.
- The model is shaded using light and colour to portray planes and curves. The appearance of metals is simulated by the specular properties of the respective surfaces.
Screen shot of boiler showing a transparent interior view.
- The ground plane below the model is shadowed to give a visual reference for up and down.
- The assembly is smoothly switched and animated to the next view selected by clicking the appropriate single icon.
- Other, non-orthographic views may be selected by spinning the model freely in space, like a flying toy in suspended free fall.
Assemblies
Within the graphics window, every part and sub-assembly is labelled with the component name as the cursor passes over it.
- The component build structure of assemblies is listed to show all the items within them i.e. a full parts' list.
- Easy identification is made of the part in the assembly since it changes colour in the graphics window as the part name is clicked in the parts’ list window.
- Assemblies or components may be separately viewed to show variations in design. For example, both gas and spirit-fired variants are shown. The two different configurations can be selected for separate viewing.
- Multiple or repeated parts are quantified by number within the parts-manager window of the viewer.
- Drawings of the finished locomotive with its tender are provided and treated in the same way as the model but the output is placed within a drawing boundary which can be output to a printer. The drawings are suitable for framing and wall hanging, subject to the availability of a suitable colour printer.
Cross-sectional views through structures
- Sectional details can be selected and viewed as sections through the assemblies in any of the XY, YZ & XZ axes and in any position along the length, depth or height of the model.
- The edges of components can be illuminated to define their boundaries in red as they touch the section plane. This helps to show the surface limits of the components at the plane of the section.
Cross Section.
- The position of the section plane may be moved up, down and along the model simply by pulling the plane through the model with the cursor. The visual effect is similar to a medical CAT scan of the human frame or a bacon slicer.
- Sections can be established on any available plane surface of the model, which may be at any angle within the structure. These auxiliary views can be viewed in registration with the primary view or in a perpendicular direction, so that clearances around the item can be confirmed when an item is not aligned with the main axis of the model. For example, the clearance between the trunk-guide tube and the front axle.
Viewability
- Components may be grabbed and lifted from the model assembly for closer study of the component or to enable the user to view hidden details.
- Following partial or full disassembly, the model rebuilds itself instantly at the click of a single 'Home' icon.
- The changes applied to the model by the user are not permanent and clicking the 'Home' icon smoothly re-establishes the integrity of the model.
- Parts may be made transparent to view internal drilled holes or cavities, such as those in the cylinder or the valves within the steam chest.
Cylinder solid or "see through"
- Parts may be hidden completely to make assemblies simpler.
- An individual part may be selected from the parts' list and every other part in the assembly may be hidden at the click of a button, so that the specific part may be studied separately.
- Difficult assemblies may be viewed 'in place' by switching the visual properties of the obscuring structures around them from opaque to transparent.
- All views can be zoomed, rotated and panned.
- Areas of special interest can be windowed and maximized to the screen for close viewing and print out.
Animation
- The moving components of the steam cylinder and motion are provided as an animation. These may be set to run for one cycle, continuously or forward and reverse.
Mark-Up facilities
- The viewer enables typed text comments to be added in the form of 'Cloud references' to comment on details in the course of construction. This is useful for adding drilling and tapping sizes to the drawings before the printed output is taken to the workshop.
- The particular drawing with added comments can be sent to other hobbyists via e-mail in order to seek or give advice about specific problems.
- Comments are numbered and can be specifically replied to with an associated comment added by the person assisting you.
- Comments can be accepted, rejected and/or deleted.
- There is even a place to record the contact details of the individual who has sent the comments back to you.
- The comments facility provides a set of graphic sketching tools. The tool allows lines, rectangles, circles, arcs and splines to be drawn onto the component drawings and saved to your hard disk.
- A blank drawing sheet is provided to enable simple sketches to be created and sent via e-mail to others.
Printed output
- All screen images can be saved in numerous formats for inclusion in other documents and or instantly sent to your PC's printer.
- The output is of suitable quality for presentations or wall pictures, depending on the PC printer's inherent quality.
- The output may be black and white with the hidden lines removed or fully coloured.
- The screen colours may be optimized for user preference: background colours, highlight colour etc.
- All views may be portrayed as true plane projections or with correction for perspective.
Screen shot of close up view of the valves and pistons in situ.
Bonus reference material is usually included on the disk in the form of a video and a short slide show of stills showing details of the fine models.
Why not contact me if you are interested in giving your pride and joy (locomotive design) similar treatment? lets talk