Modelling and Boning a 3D Crane in Autodesk 3DS Max

As one of my very first serious ventures into 3DS Max, I thought it would be sensible to document my progress. In this case, I am modelling a robotic crane arm that would be seen in a mechanical working environment to pick up and manipulate parts.

I have taken screenshots of the modelling process from start to the boning process (which according to the graphics pipeline is the last remaining task of the actual modelling process) - the rest of the process covers such things as texturing and lighting the model, but requires no actual manipulation of the polygons.

The first process was to block out a general shape from the reference picture that was provided. This entails using primitive shapes for each segment of the model, that will eventually be manipulated further to more closely resemble the real life counterpart in a more detailed manner. This can be noticed throughout the modelling process that I document below.



Starting off, I created two very simple shapes - a cylinder (in the purple) and a box (in the green). These shapes, as aforementioned, are simply placeholders that will be edited in more detail at a later stage in the development.

This is what the model looks like when the blocking out stage is finalised. The next step is to position the segments correctly. This isn't always applicable, but in this case it was easier to create all the segments exactly upright or horizontal and then rotate the pieces into their correct location.

The following step is to start adding some basic details to the primitives that contain the basic shape of it's real life counterpart already. For example, the green box contains the general shape that can be seen in the reference picture and therefore only needs small tweaks and added details to acquire something that resembles it even more closely. These details may be very small, such as simply rounding off the box or adding in smaller cylinders, as you can see below.

Detail then follows on the cylindrical part of the model, which consists of using methods like extruding and selecting specific edges and faces. The result was a further detailed base for the model.

When detailing the blocked out model, it makes sense to go from the ground up on a prop model like this crane. So the next step was to shape the small contraption that allows the arm to rotate backwards and forth. I decided to also add in some extra detail while I was working in the same area.

Working my way up the model and gradually detailing it further, I hollowed out the big block that acted as the arms between the upper and lower portions of the crane. I also duplicated the lower connection mechanism and moved it into place ready for when I work on the upper part of the prop.

I then duplicated the mechanism once more and moved it further up the same piece of the upper part of the crane. At this point, I realised I will need to edit a part of the model that is at a slant. Due to the nature of the program and how it works, it's a lot easier to work on a model when it's on a 90 degree plane. This is when creating an instance comes into great use - by creating an instance, I can create an exact reference copy of a certain part of the model. Once I had created the instance, I rotated it to a 90 degree plane. I then make the changes required to the piece of the model, using the 'Attach' tool to denote to the program that it is part of the reference. The changes made are then applied to the original copy of this piece of the model, and are automatically rotated into place.

Once happy with my reference's looks, I deleted the block-out primitive and the cylindrical detailed shapes were left remaining.

Then, still using the reference, I added some extra detail onto the cylindrical mechanisms. I added faces / plating that would hold and support the mechanisms in place while attached to the primary rotary arm.

Before I decided to move onto the main attraction of the arm - in a Toy Story Alien voice: the claw! - I wanted to add some more intricate details, quote similar to others already applied, to the newest addition to the model. I added two, thin cylindrical like objects to either side of the claw-close end of the secondary arm.


Now, work begun on the claw part of the model. It was the most modelling-heavy segment of the whole project, however I was very happy with how it turned out. It began, such like the blocking process, with a simple primitive block. I then chamfered the edges to get a smoother and rounded look to the block, before placing in a cylinder and intersecting it half way into one side of the block.

I was aware at this point that I was only creating half of the claw, as I would duplicate and mirror the other half from the existing half. This method works due to the claw's symetrical nature.

After applying some more detail to the block, I mirrored it and attached it to the instance copy. The result was pleasing and I was beginning to grow happy with my model.





The next step - now that the model is created - is to bone the model. This process gives the model a skeleton (rigging it) and prepares it for animation. This process allows me to set certain bones and attach them to certain segments (one or more) of the model. I can also set which parts of the model get affected by certain movements, and using a painting method I can allocate tension and how many segments get affected by each bone.





Now that I have completed the modelling and boning process, my model is now ready for animation. Animation can be done within 3DS Max or you can use a different animation program. The possibilities are endless and I'm very excited to see what I can do with the program a few years from now.