User:J4knee21/enes100/My Work

Write problem/project Goal
A more sturdy robot arm configuration must be built to pick up, move, and set down objects. It also must have interchangeable hands between fin ray and coffee ground.

My First Task
Design a valve that can be controlled by a motor to allow and restrict vacuum flow.

Summary of actual work over first weekend
My work over the break was in no way different than my original task.

Week1 Narrative
I began my weekend using an idea with a wheel which controls the valve itself. The problem I had was that it is difficult to move a wheel forward and backward using only a string attached to a motor. I decided I needed a valve that would close by itself and could be opened. So I decided to use an air blowing nozzle that is spring loaded. By using a pulley it can be opened and then once tension is released it will close on its own. A 90 degree extension on the lever will allow downward pull to control the flow. I believe this will work well and be very inexpensive.

My Second Task
For the second week my task will be to build and test a model of the coffee grind robot end effector.

Summary of actual work over second weekend
My actual work over the weekend stayed on track with what I had set out to do, building the hand. But I was also struck by an idea which combines both the fin ray and the coffee grind hands. It is a hybrid of both that combines both of their gripping power. I may look into this once my original goal is met.

Week2 Narrative
The actual work I did this weekend was directly on track with my original goal. Using some parts I picked up from Lowe's: 2" coupling, 2"bushing, Sink drain with threads, blow gun nozzle, and some birthday balloons, I was somewhat successful. After putting them all together I hooked it up to the vacuum where I discovered a few problems. First of all my balloon was to small and was too constricting to get a good wrap on most objects as seen in :[|Coffee Grind Robot Hand]. Which I hope to fix by getting a bigger balloon. Next once I let off the trigger of the blow gun nozzle there was still a vacuum. So I need to come up with some kind of pressure relief valve.

My Third task
My third task is actually a combination of many tasks. First of all try and fix the problems previously stated I was having with the coffee grind hand. I will try and find a better balloon replacement and I will research and develop and pressure relief system. But also I will look into our method of suspending the hands in a fashion that is interchangeable, sturdy, and again very inexpensive.

Summary of actual work over third weekend
Over the third week my focus was on the original tasks. Which were increasing the gripping power of the hand itself and concocting a plan that to suspend this in mid air. However, I did not get a chance to look very far into the pressure relief valve configuration. This is because I felt I needed to know how my fellow teammate planned to control the original vacuum valve first.

Week3 Narrative
Over the third week I tried several different combinations to try and achieve better results. I went to party city and got the next two sizes of balloons bigger that I could find. Which were the 12" and the 36". Also I decided I would try and use a fine sand called Berkeley springs finely grated sand in replacement for the coffee grinds. I tried both coffee and sand in each of the new sized balloons and got some great results. I found the 36" balloons were way too big and not effective whatsoever, I wouldn't recommend using them, but the 12" balloons showed improvement. The sand proved to be especially effective vs the coffee : [|End Effector Round 2]. I also derived a method of attaching the hand to the wires controlled by the motors. It is very simple, but I feel like using some large hose clamps to a threaded bushing would be sufficient.

My Fourth task
My fourth task will include more work with the coffee grind hand. When playing around with it I found I am losing vacuum because of a faulty seal somewhere so I will look into this. Next will be a lot of work. Including making the table and adding my work to my teammates work to have a hopefully completely function ending model. To add my work I will have to create the attachment for the hand and use some wood working skills to create the base.

Summary of actual work over fourth weekend
What I worked on for the fourth week was right along the same lines as what I had planned. I needed to find a way to keep a better seal within the hand. But I am having a lot of difficulty.

Week4 Narrative
The problem with the suction is one that I honestly should have realized sooner. But the fact that I have realized this is still good. Now the problem seems to be attacking me from several different angles. I believe that the problem could lie just in the threaded portion of the drain itself. But after using Teflon tape I did not get quite the results I would like. So my angle of this week was the try and design a method of changing out the balloons in a secured fashioned drain. To do this I noticed in the center of the cross hairs at the top of the drain is a threaded hole. So I could use a tube with threads to hold the balloon in place. Just make it so that the balloon could be fashioned to the top and then screw the tube into place. This way it will be more securely fashioned into place.: [|End Effector Round 3] The problem with this is that I am having trouble finding exactly what I need as a piece. I have found that the size thread i need is a 7/16", but fitting that would work only come in different sizes. To take care of this I thought maybe I could drill the hole out and fasten a nut to the top of the cross hair region. But the hole is already very thin so if i do this I am afraid it will be way to easy to break. The other thing that jumped out at me recently is that it may not only be the threads. It could be that the shape of the drain does not work well with the balloon. Pressing a piece of PVC onto a balloon creates a really good seal I have noticed. So I thought maybe if I put a piece of PVC and extend it downward in the drain for the vacuum to be created. With this, however, the balloon tends to be sucked up into the pipe and could result in a rupture. So possibly if I put some screen over the pipe it could solve all of my problems. Which I will soon find out.

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