Storytelling With Robotics

Project Statement:       The aim of Project 2 was to create a motorized automata - an apparatus that can translate rotational movement from a motor into a small scene that tells a story. My concept from the beginning was a dock scene with a fisherman pulling up a crab pot from the side of the dock, and throughout the project the crab pot became an assortment of garbage to produce an environmentalist message about cleaning up the bay.       With this project, I wanted to challenge myself by designing a custom mechanism that would create the effect of an object on a rope being pulled up by a person and then gravity pulling it back down. This entailed making cams with arms that could push down the rope holder with enough force to lift the weight on the other end. To facilitate the up and down movement of the rope while minimizing lateral movement and friction, I designed a custom rope holder apparatus. The final key parts of the mechanism were the ge...

Once the mechanism was functional, I needed to paint the entire apparatus, attach the wooden boards and pilings, and make the figure standing on the dock.  An important consideration was ensuring that nothing would interfere with the rope. It could only be affected by two sources: the platform being pulled down by the cams, and gravity pulling the weight back down the other direction. To ensure this, I cut one of the planks in half to allow for a hole in the middle of the dock.  For the paint, I did a base coat of brown and then went over some parts later with gray-blue and green to give the wood an aged effect. I also painted the bottom a bluish color to seem like water. The next part was to make the figure. My original prototype was made of aluminum wire, and I had assumed this would be temporary. However, I couldn't really think of a better way to make a movable figure. I thought about 3D printing it, making it out of clay, or fabric, but all of these options either require...

My main focus at this point was finalizing my mechanism. I 3D printed the posts for my rope holder platform as well as a duplicate of the platform itself. One of the platforms would serve as a base with ready-made slots for the posts, and the other would move with the rope. Luckily, the 3D printed posts had much less friction, but still enough integrity to stop the platform from moving left and right or forward and backward. I ended up having to reprint my cams because the arms on the first version snapped off. I added a taper to the arms to increase their strength. I also tried adding set screws, but the holes were too small. The central hole for the shaft on the second version of the cams was also too big, so I tried resin printing some plugs for the cams so that they'd fit on the shaft. This didn't work super great because I had to break the plugs a little to get them to fit, but ultimately it made it possible for the cams to be super glued to the shaft. I also printed and a...

The next part of my mechanism that I worked on was the loop that the string would go through. It's made out of the same metal rod as the shaft, and the idea was to incorporate this metal piece into the figure pulling up the crab pot. For this reason, I tried to bend the metal as if it were the leg of the fisherman.  The next part would be one of the most challenging aspects of the project. The rope needed to be able to move freely up and down while being constrained from moving side to side or forward and backward. The end of the rope not attached to the crab pot also needed to be able to be pushed down by the rotating pieces attached to the cams. I prototyped a four-cornered platform like the picture below, with hand-cut posts and a 3D printed rope holder. This had the right movement, but the wooden posts caused a ton a friction.  Here you can also see I've moved to two cams, one on either side of the platform because I needed equal pressure on both sides. The free-moving asp...

The first part I decided to make was the wooden boards for the dock. I had ordered some wooden dowels of 1 inch diameter for the pilings (the poles) and I wanted to make sure the boards would look like they had the right scale compared to the pilings. To make the boards, I sawed balsa wood on the band saw. Since I wanted the dock to seem somewhat old and weathered, I wasn't too worried about making perfect cuts. Some inconsistent spacing between the boards was also fine, in fact it was better, because real docks warp over time. Looking back, it would've been interesting to add some manual warping to the boards. I also started brainstorming how I could make the figure standing on top of the dock. Since I had ordered some aluminum wire with the intention of using it to make my crab pot,  I tried shaping a figure out of it. Additionally, I drew some sketches of how he should be standing based on reference images of people pulling heavy objects with ropes. You can see that I haven...

For Project 2, we had to make an automata, a motor-powered mechanical device that does some kind of movement. When I saw the dimensions of the wooden box in the example project, I immediately thought of a fishing dock. My family lives near the Chesapeake Bay, and we have family friends who have a dock behind their house, and they have crab pots hanging off the side of their dock. I decided to try to create a movement with my mechanism that would look like a person lifting a crab pot up and having it fall back down.  Here are some of my sketches brainstorming the look and mechanics of the automata. I was thinking about how I could maybe use a belt or a cam to create the motion, but the hard part is that the box needs to move in the opposite direction to the motion.  I was also thinking about ways I could get the figure's arms to move with the rope to make it look more like he was pulling it, but this was a not a huge priority. Originally, my plan also involved 3D printing a lif...