Padlock Project

Research began with the purchase of a transparent lock meant for lockpicking to assist in understanding how a basic lock functions. 

Using a digital caliper, physical measurements were taken of the model. Although these were not used in the final design because they were often strange values, likely due to imprecise manufacturing tolerances, they served as a useful basis to design a replica.

To assist in orginization, a naming convention was chosen. This takes on the form: Lock_<Partname>_<Version#> for parts, and Lock_<Partname>_<Version#>_Drawing_<Version#> for drawings.

The first component designed was the shell of the lock. This was decided based on the fact that all other components needed to fit inside the dimensions of this part.

One of the most complex individual parts, the lock slot is the main part that allows the key to interact with the padlock. Comprising of 6 holes, a slot, 2 pins, and a channel for the key to slide through, this part required a deep understanding before it could be properly created.

Due to the multiple cuts, revolved features, and sweeps dependant on dimensions of other parts, this part was particularly challenging. It was critical that the part be precise while also allowing for a great degree 

Although all based from the same original model, each pin has a different height, corresponding to how far the key must raise it so that the lock can be opened. the radius along the top of each pin is also the same as the Lock slot cylinder.

Each pin is identical, all serving to transfer the pressure of individual springs to their corresponding lock pins to keep the lock engaged when a key is not inserted.

The two loop locks serve as the main components that prevent the loop from moving when the design is in its locked position. When the lock slot is twisted, each loop lock pulls inwards and allows the loop to move freely.

The loop stopper functions to prevent excess vertical movement of the loop.

Although an aesthetically simple design, the key needs to be precise for the entire lock to function properly. Each ridge on the lock corresponds to a lock pin height.

Because of the many fine details and complex geometries, this drawing was particularly challenging to create well. 

Similarly to the Lock slot, this part was feature rich and difficult to create a well dimensioned drawing. Ensuring that there were enough views and dimensions so that everything was clearly defined, while at the same time not having multiple instances of the same measurement was particularly challenging.

In an effort to make the assembly model act as it would in real life, I utilized a set of multiple configurations with different constraints and mates to model real physical behavior.

Initially I had wanted to put dynamic springs in the model, however even when they were correctly modeled as parts they created issues at the assembly level. I chose to leave these out of the final model as they removed the ability for the model to be interacted with.

Demonstrated by the exploded view, the final assembly consisted of many individual and unique parts. All of these parts interact in realistic ways with each other. Although a challenging project, it was enjoyable and taught me many valuable lessons.

The most valuable thing from completing this project, in my opinion, was the experience and practice gained in designing and constructing assemblies of my own design.

The most impressive part of my project in my opinion was the ability to be physically interacted with. This was a choice I made, and was not a requirement. It is easy enough to make a fully constrained model where no parts are free to move, or a model where multiple configurations correspond to different static states of the model. However, it is far more challenging to create a functioning assembly where all parts interact with each other to model real life behavior.