Origami Tower Bridge (London) With a Working Drawbridge

My project is an origami model of London’s Tower Bridge that uses folding mechanisms to lift both sides like a real drawbridge. Each side is folded from a single sheet of paper, and the design uses origami techniques (such as boxpleating) only; no tape, glue, or cuts.

Supplies needed were quite simple:

1. 2 pieces of kraft paper.

I cut both pieces from a roll of kraft paper. A paper cutter was used to prepare the paper only.

The following section goes over my entire design process from conception to final model.

This step is trickier than it may seem because not all subjects work for origami. Buildings with complex curvatures are often impossible to capture with folds. I eventually chose London’s Tower Bridge because I wanted a structure that could move. That made it a perfect fit for an origami action model, where you move one part of the paper and the model responds with a different motion (like a built-in mechanism). Thus the drawbridge was perfect. The tower shape at the ends of the bridge are also optimal because it is symmetrical.

This is the first step in the origami design process. There are 2 main goals for this step:

1. Decide how many pieces of paper you will need to make the subject
2. Make a crease pattern, a diagram showing all the creases of an origami model as if it were unfolded. (That's the red and blue line diagram above)

I usually start by sketching the subject and simplifying it into basic shapes and marking where each flap will go. I decided to use two sheets of paper for the bridge, naturally splitting the design into two halves.

Next, I needed to plan the crease pattern out. In origami, any appendage or long extension is treated as a flap, and breaking the design into flaps makes it easier to plan the crease pattern. For example, a flap for this subject might be the tower itself. Additionally, there are also extrusions such as the wired supports coming from the tower flap. To make a crease pattern, I used a method of design called box pleating, which is ideal because it’s geometric and uses only straight creases that are parallel or at 45°. I drew the crease pattern in Oriedita (shown above). Using other design methods (that may have creases running at 22.5 degrees or 15 degrees) would be better for something like a pyramid or the Shard in London.

I look at my simplified shape and arrange the flaps according to the given shape. This process takes time and patience, but I eventually got to an initial flap arrangement I liked. You can see my arrangement above in the crease (red and blue line diagram)

My next step was to prototype the initial design I came up with. Let me tell you, this was rough. Many flaps didn't turn out the way I wanted them to, and it just didn't look like a bridge. This was mainly due to the fact that I didn't simplify the shape enough, the geometries were still far too complex for origami adaptations. But I didn't see this as a setback because this is all part of the design process. This is why I prototype, because theoretically, things can work, but they may not always be feasible in the real world. In the next step, I improve upon my design by reorganizing my flap arrangement and making simplifications.

I changed my design to include simpler geometries and a more efficient flap arrangement. In origami, efficiency refers to how many flaps you can create with the amount of paper used: using more paper for the same flaps is less efficient, while using less paper is more efficient. In this step, I finalized the bridge design and flap arrangement. Overall, during this step, I increased efficiency by 20% just by reorganizing my crease pattern.

Above are progress photos of this second prototype. You can see the flaps sticking out and the pleats forming the main body of the tower.

In this step, I used an origami mechanism that creates rotation when the pleats are gently unfolded. This will be used to create the draw bridge motion in the final model. See the video for a demonstration of this mechanism.

With a finalized flap arrangement and the draw bridge mechanism, we can now fold the final bridge design. Above is a timelapse of folding half of the bridge. This step is relatively straight forward; I simply used the crease pattern from Step 4 and the mechanism from step 5 integrated into the model.

Finally, we made it to the end product: an origami version of the Tower Bridge in London, complete with a working drawbridge. In the video, I demonstrate how the draw bridge functions in the entire model. There is also a picture of the completed model with both sides finished.

What first drew me to origami was the design process and taking an idea in my head and turning it into something real. In this Instructable, I hope I’ve made that process clear. Origami design is also what inspired me to major in Mechanical Engineering at UC Berkeley, because origami and engineering design share the same mindset: iterate, test, and refine.

Looking ahead, I’d love to see origami-inspired patterns used more often in architecture and structures. Even though this project is a paper model, many folding strategies can scale to real applications. Corrugations, for example, can increase stiffness and strength and could help reduce material use. Additionally, the Miura fold pattern (above) is soft and flexible, but it can transform a material’s structure so that it supports up to 10,000× more weight than the same material when it’s left flat (unfolded). I see applications to origami in structural engineering and architecture, so this Origami Bridge is just the beginning. Origami can be applied to barriers, medical devices, and spaceships.

My goal is to keep exploring where origami and engineering overlap. For now, I’m happy I was able to build a working mini drawbridge. Thanks for reading!