Wobbling Bridge 2 –
I built a wobbling bridge a few years ago for the Hex House in Oklahoma. This design can be found in my other posts.
This new design lets the bridge sway (back and forth up to 6 inches) while the planks tip up and down. These movements would need to be very subtle as to not make it too difficult for people to walk on.
Also, the method for swaying can be used alone without having the planks tip. The same goes for the planks, if you don't want the bridge to sway.
Lets start with the basic design concept: A rope bridge with planks for walking on.
Once you step on the bridge it moves away from you about 2 or 3 inches. Once you are on it the bridge sways forward and back. The rope helps you keep your balance. As you walk, the planks tip up and down (about an inch).
Andrew deRuiter's Bridge 1.jpg
The drawing shows a concept I have known as the garden-swing-chair method. Some porch or garden swings use a low hanging bar attached to the seat to swing it back and forth. I took this concept and added it to my bridge drawing. You can see these bars behind the posts. One thick bolt attached to the post and to the bar. Then, at the bottom of the bar is another bolt attached to the bridge.
Andrew deRuiter's Bridge 2.jpg
This is a better picture of the posts. I drew out two legs to support the posts but I think 3 is better if someone leans too hard on them. The posts, btw will have a lot of weight keeping them in place.
Andrew deRuiter's Bridge 3.jpg
This picture shows the planks moving up and down. I figure a long pipe running down the middle will make the boards tip. Each board will need to be attached to the pipe with brackets.
Andrew deRuiter's Bridge 4.jpg
This picture shows the bridge without the planks, that is, all but one. The one is there to show how it is attached to the pipe. The framework is attached to ever post to hold it up.
There are excellent rope bridges made of cables running through each plank and again under for support. There are different options for building your bridge. I offer this design only as a creative concept. It might be a great option for a home haunt where the traffic is not as high. If you like this idea for a pro haunt, you should build one from wood first to test it. Then change the bottom frame to metal and look into stronger posts.
Feel free to look over my other wobbling bridge and any of my other designs.