Mechanics Tensile Lab Test

This week I had to hand in a Laboratory Report. The lab was on material tensile strength, looking at the stress/strain graphs exhibited by different grades (Carbon percentage) of mild steel. The machine we used was a Hounsfield Tensometer.

A part of the report was to describe and explain the equipment used in the experiment. To accompany the text I wanted some images, but I was unable to find images that represented the equipment with any sort of cohesion. To solve this I decided to take the best images I could find, whether sketches, technical diagrams or a couple of photos taken by me, and use Illustrator to create some simple vector outlines.

These show the different equipment used from the top, the Hounsfield Tensometer, the samples used, a Tinsley Strain Measurement Bridge, Ultimate Area Reduction Gauge and Ultimate Elongation Gauge.
Below are a couple of pictures I took of the experiment at the time, they weren't too good but I did use the one on the right for the Bridge.

Finally a couple of graphs from the results of the experiments. The one on the left shows the stress/strain curves of 0.1%, 0.2%, 0.4% and 0.8% Carbon Steel, while the one on the right is the Elongation, Yield Strength and Ultimate Tensile Strength against the increasing Carbon %.

Product Decomposition- NERF Maverick

So for today we had to prepare a presentation for mechanics on the mechanical workings of a simple. The idea was in groups of five to take a simple product, take it apart, documenting the stages and each individual component, and then demonstrating how these pieces interact, facilitate the flow of energy and contribute to the overall function. We were in a three, and the product was surprising complicated.

 This was the item in question, one NERF Maverick toy gun. The gun is designed to shoot small foam darts and then have the barrel rotate a new chamber into position. So we set about disassembling it, removing the multitude of screws from it to reveal....

 A very complicated interior mechanism. We had chosen this because we knew it was completely mechanical, with no electronics so we knew it would be complicated, but still we were somewhat surprise when this jumped out at us (literally with some of the springs). 

 

 So as we deconstructed it we recorded our progress, neatly laying out all the parts and photographing them with their corresponding components, till it was completely apart, as shown above and below.

 Once it was in pieces we then set about photographing the different components, 35 varieties in total with some multiples.

Disassembling the mechanism.

From this procedure and the photos we had taken, we were then able to create a Product Decomposition Report. This involves labeling, and providing information such as how it was manufactured, on each component, detailing how each component interacts with other components and other objects, detailing the overall function, the flow of energy, information and materials and flowcharts on the function and subfunctions. Some pages from the report are below.

 

 Then from this report we (well...I) made this presentation (again only some pages shown below), presenting the information from the report with a mood board at the end, to be presented in class today.

 The presentation session was scheduled from 4pm-6pm, but ended up taking until 7pm, as groups required more time. Other objects chosen included two identical staple guns, four corkscrews, a stapler, a lighter, a garlic slicer and two tape measures, all with less than 20 parts total. So yeah ours was overly complicated. But the presentation still went well, and the lecturer seemed happy with our efforts, so a success, I think.
Anyway I now need to get on adding the finishing touches to the foam models as they are due tomorrow so better crack on.

Hole Punch Surprise Presentation

OK so I'm not 100% sure why I'm uploading this but oh well. This is the video from a surprise (for me) presentation I had to give on the Not Hole Punch Hole Punches I designed earlier for this module (Mechanics for Design). Also the reason for getting a friend to film this for me is not just for this, but also so I can evaluate my own perfomance so I can improve for next time( tip from the Core77 website).

The full story is that we were told this morning by email that we had to give an under 3 minute presentation on the best of our designs to the whole group. I got to the lecture slightly early and ended up talking to the lecturer (he had interviewed me for my place). Whether it was from this or not, I ended up being the first one to give the presentation. In the presentation we had to explain these points on our design:

• The overall function
• Processes-Input and Output
• How it works
• The strengths and weaknesses of the design

As I was first I didn't have any questions to answer and I felt it went okay considering the circumstances. Of course I then had to sit through the following 3 hours of presentations and the lecture that followed (following the 4 hours of lectures this morning). But not too bad all the same. Anyway lots of sketches due for tomorrow so I better get on with them.

Not Hole Punch Hole Punches

Today was a free day so no lectures, so I was able to get lots of work done.
In Mechanics I was given this brief:

•  Design a device for making two 6mm holes 80mm apart and 10mm from the edge of a sheet of paper

So yeah, a hole punch..... that isn't a hole punch.So anyway here are the designs I have come up with, to be honest I think the last one is my favorite one, you'll see why.

So there we are, hole punches that aren't hole punches..... sigh.... what next?