Testing with the Weight

Today we tested our trebuchet with the weights! It went fairly well, and thankfully didn't break. It went a bit further than the other ones I have seen, so I am pretty pleased with that. We didn't actually measure the distance it travelled or the time it took today because we just wanted to make sure that the angle for the cup holding the ball was right. We glued on the cup and the triangle that it sits on today, after making sure we were satisfied with everything. The wheels have also been made and attached. We also decided to spray some grease on the join between the washers on the arm and the nut, to ensure that the least possible amount of energy is lost due to friction.

The only issue that we are currently having is that unless it is set up with a lot of care, the weight will hit the sides. This means that it doesn't swing completely, and loses a lot of force and energy on the impact. However, this shouldn't be a problem on testing day, because now that we know it happens we can take care in making sure that it doesn't happen on the day.

Below is an image of our completed trebuchet.

Beginning Testing

Today, at the end of the lesson, we tested out trebuchet. We didn't attach the weights yet, but instead just pushed it down. We only wanted to see the angle that the ball would go in, so it didn't need to travel very far. As it was, it went reasonably well, but perhaps slightly too vertically. By changing the angle of the small triangle on the end of the arm, we could make it travel further in distance than it currently is. We did not have time to do this though, because we only began testing it in the last 15 minutes.

During the lesson we also attached the arm with the metal dowel, nuts, and washers, as well as drilling the hole through the end where the weights go. We are getting very close to finishing now, and only really need to do the wheels and adjust some angles on the arm, as well as possibly supporting some areas more if they are put under too much stress when the weights are attached. We are definitely well on our way to finishing, and I am really pleased with our progress. Some images of our trebuchet currently can be seen below. Part of the arm came off during testing, so it is currently being glued back on.

Nearly Completed

Emily and I have now nearly completed our trebuchet. We completed both sides and drilled the hole through the top. Then made the arm and attached it with just the wooden dowel for now. The only issue I have with it currently is that the holes are very slightly lopsided, so that one of the sides is slightly lower than the other. This will probably end up placing more pressure on this side, and could lead to our trebuchet's demise. Hopefully it will probably be fine, and if not we can just place extra supports on that side.

With the catapult arm, Mr Ward said it may be stronger if we glue three pieces of timbre together for the entire length, rather than just around the join. We have not done this, because it was said after we finished, but I still wouldn't have done it anyway, because it would add extra weight to the end with the ball that is being thrown. This would mean it would take more effort to throw the ball, and more energy would be lost, and that end of the arm really does not need to be supported because it will be lifting minimal weight. Instead, we have just reinforced the end with the weight itself, and the join, which I think would be more effective.

We still haven't actually gotten around to making our catapult into a trebuchet, and at the moment I am beginning to doubt that I'll have time. No one else has done one either yet, so it shouldn't matter too much. We could possibly go in to work on it in a few lunch times, but we are running out of time to even do that.

Trebuchet Progress

So far Emily and I have completed one side of the trebuchet and have begun work on the other side. We were working fairly slowly in the beginning because we weren't sure on what to do and had to discuss most things, but recently we have been doing things more automatically and it is progressing much faster. The main issue we have encountered is that the nails are too long for the materials we are using. Even if we use the smallest ones, they will still go all the way through the wood. This is an issue as it is splitting the wood and would definitely be weakening the structure. We have glued extra pieces over the top of parts that have been particularly affected by this to try to hold it together, but that is fairly time consuming and won't solve the problem completely. Other than that, the machines seem to be fairly crowded because it is such a large class, and it is quite slow when you have to return to them frequently to make small adjustments to angles. That can't really be helped though.

If we have time at the end we are going to add more supports to each side to strengthen them even further, so they will hopefully be able to hold even more weight. I am fairly sure we are on track to finish by the due date, and am quite confident that our trebuchet will operate well on the day.

Progress

Trebuchet

Recently we were given the design brief for our new task. We are to design and fabricate a trebuchet capable of propelling a golf ball as far as possible. I am going with Emily for this task, and we have decided that we would like to attempt to make a trebuchet instead of just a catapult, and if it doesn't work we can just revert back to the catapult design. This week we are working on designing our trebuchet, and researching some of the history surrounding them. Hopefully we'll be able to start in the workshop early next week.

Completing my car

A few days ago, my car crashed badly into the end of the track as there was not enough padding, and it slightly ruined my car. It jarred the axle housing, making the car not run straight. It also jammed the wire at the front into the gap at the end of the track and the wheels stopped staying on. It made the time drop from 2.856 seconds to about 3.8. I fixed it as best I could during lunch times as we did not have anymore lessons, and managed to get the time down to even faster than before. In one of my final runs, I got the time of 2.774, which was my fastest. After this I stopped racing it as I did not want to risk anymore complications.

Since my last post, I lubricated more, glued on one of the wheels to make it more steady, and shortened and soldered all of the wires. I also attached a windshield to the front of the car.

Below are some images of my finished car.

This has been one of my favourite units so far, and I wish we could have spent longer on it so we could experiment more with different designs. I am definitely looking forward to racing the cars on Monday, but am also slightly worried that mine will not perform as well as it has been because I have been experiencing complications lately. Hopefully everything will be fine, and even if it isn't, I know that I have made my car as well as I could have and am very satisfied with how it has done.

Progress on car

Since my last post I have glued on the engine, switch and batteries. The first time I raced my car, when it hit the end the engine and switch came off. When gluing them back on, I used much more glue than the first time. Every single time I have raced it after that, one of the batteries has come out when it reaches the end. I don't think this is a problem, if anything it is better because it automatically switches off after every race.

I am fairly happy with how it has been working out so far. In the final few lessons that we have I am going to work on changing small things to improve its speed. I can lubricate the axis that the wheels are on, as well as the side of the wheels that comes into contact with the body. On top of that, I can lubricate the wires on the front and back end, and shorten all of the wires. I also need to solder the wires near the end of the process. If I feel I have time, I wouldn't mind testing out the engine with the smaller cog to see if it works any better.

Images of the progress on my car can be seen below.

Reverting to original design

I have changed my mind about the location of the engine again. I am placing it under the body, like I was originally planning on doing. There should be plenty of space under the car, and if the batteries are placed towards the back, the weight will be centralised in the correct location anyway.

Change to design

I have decided to place the engine on top of the car, with the batteries angled on top of that. This is because the engine would have to be quite far forward in order to match the cogs if it were underneath, and this could make the car more unbalanced. I think it would be more important to have the car less aerodynamic but more balanced, than unbalanced and aerodynamic.

I have also progressed further in the creation of my car. I have attached the large cog and wheels to my car. It goes almost perfectly straight, leaning a very slight amount to the right, but not enough that I bothered fixing it. An image of my car so far can be seen below.

Starting making my design

So far we have had a couple of lessons on designing/making our cars. I have made the body of it and attached two thin pieces of wood to the base of this to give more support to the plastic for the wheels when I attach it. I changed the body of the car so that it is curved on the front. This was done to make it more aerodynamic and an easier shape to attach the barrier at the front to.

In the next lessons I am going to attach the wheels and make sure that it goes straight, before attaching the cogs and gluing on the engine, batteries and switch.

Ideation

In class today I designed the first cart that I am going to make. The body is going to be made of coreflute, so it will be very thin and light. The motor is going to be placed under the body to make it more aerodynamic. The batteries will be placed near the back of the car to keep the weight centralised slightly in front of the back wheels. A scale drawing of the design can be seen below.

I am thinking about making a later design for my cart using ProDesktop, because then I can get the measurements more exact and the materials will be lighter. I would be able to extrude two holes through the body for the metal pole that the wheels are on, and this would be perfectly straight. I am not sure of what design I would use for this yet, or if I will even have time, but I would like to be able to at least try it.

Theory Lessons - Things to keep in mind

Design tips:
-Lubricant on copper wire at the front and back of the cart, as well as on the metal that the wheels are attached to.
-Weight centralised just in front of the wheels
-Piece of plastic in front to divert the air more smoothly, making the cart more aerodynamic
-Make the cart as light as possible, but not so light that it would flip.
-Thinner body of cart is faster -By changing the positions of the large and small cogs, the cart can either have fast acceleration with a slower top speed or slow acceleration with a very fast top speed.
-Taking the outer layer as well as the silver piece of the wheel helps.
-Higher quality batteries can help slightly

Torch Completion

I have just finished making my torch and am quite pleased with how it turned out. I brought a laptop home tonight and was fiddling with the program, changing little things in the design until I was satisfied. I made each part of the torch several times, each with a small detail changed in it until I decided on the one that I liked the best. For instance, in the barrel of the torch, I made it with the helixes both extruded subtracting material and adding material, and also played with the diameter of each helix. I did similar things with the other parts, but in the end decided to keep them fairly simple because the barrel was already rather complex. With the top cap, I changed it slightly from my original design, adding a small lip at the top to form a small amount of protection around the glass that would cover the reflector.

I am going to try to take home a laptop again on Thursday or over the weekend so that I can make any final adjustments to my design, make the engineering drawing and print out all of the components. I am also planning on beginning work on the written component tomorrow. I have planned out in my head what I want to include in all the different aspects of it, so hopefully it won't take too long.

Also, I am very excited for our next unit of work! I have been looking forward to it ever since it was first mentioned. I have a very competitive nature, and due to this I will probably put a lot more effort into the task than is necessary, but will certainly have a lot of fun while doing it. I am aiming to be able to beat Mr Ward's time, even though I know it is fairly unlikely.

Torch Design Decision

I have settled on a design for my torch. It will be a generic torch shape with spirals around the barrel of it. I am not sure if it will be possible to have multiple spirals crossing over each other yet, so I will try it and if it doesn't work I'll just have one. I haven't done a spiral before, but I found an exercise in the textbook, using the sweep tool, that is fairly similar to what I want to do, so I can modify it to fit my needs. The spirals, while adding interest to the barrel of the torch, will also provide a more rough surface, thus causing more friction between a hand and the barrel. This will make it easier to hold on to than a smooth surface, making it more effective for protection.

The end cap is square, with straight, relatively sharp edges. During a potential attack, these could be used for self defense, while not putting the user at risk. The top cap and reflector are similar in design to other torches.

A scale drawing of my design can be seen below:

Ideation

I began properly ideating today and I now have three main ideas. The first is to make the torch in the shape of a gun. The batteries would be situated in the handle, and the switch to turn it off and on could be the trigger. This would mean that the torch could be quite small, but still detailed to fit in with the design brief. It could also be good for deterring potential criminals as it would look threatening even though it is harmless.

My other two ideas are both modelled off items in shows/movies that I like. They are a sonic screwdriver from Doctor Who, or a wand from Harry Potter. Both of these series' have large fanbases, and the items would therefore attract a large audience. I am leaning more towards these two ideas than my first one as I think they would be more interesting to make and also fit better with the conventional torch shape. Images of both the items can be seen below.



At the moment, I cannot decide which I prefer between my second two ideas. I am interested in doing the wand because I have been wanting to learn how to do a spiral/spring for a while, and I could include it in the embellishments of the design if I chose to do this. On the other hand, the sonic screwdriver is a better shape to fit all of the pieces of a torch. As it is slightly wider, it would be better for accommodating the batteries, reflector etc. I am going to continue looking for more ideas in the lesson tomorrow to see if I can think of anything better, or improve on the ideas I already have if I can't think of anything.

In today's lesson I completed the pen assembly, meaning that I have completed all of the exercises that need completing, so I can now focus on ideation for my torch. I do not have many ideas yet, but in the next lesson I am going to look up different images to try to decide on what I would like to do.

ProDesktop Progress

Since my last post I have made a lot of progress on ProDesktop. I have completed most of the tasks required for the assessment. These are both toy blocks, calculator, clock face, cart wheel, phone, energy drink bottle and aluminium motor cycle wheel. I found the aluminium motor cycle wheel to be the most challenging as it did not give much explanation on how to create it. It also involved using most of the tools that we had used so far, and adding on the mirror tool. While it wasn't exactly difficult to make, I found it hard to make the shapes similar to the ones in the design. Even so, I am pleased with the end result of it.

I have had an issue with the file for my phone. Last lesson, just after I had completed it, the program crashed and damaged the file so it won't open. Mr Ward has said that I don't have to redo it, but I am still slightly annoyed because it had taken a few lessons and I was really proud of how it had turned out. I had put in a lot of detail into the design. For instance, where there were extrusions subtracting material below the workplane, instead of just leaving it as a hole, I had either rounded or chamfered the edges depending on what was on the phone to make it as accurate as possible. I had also done all of the measurements very exactly to make it as well as I could. I was planning on adding the text on the back and attempting to create the Apple logo as well, but the program crashed before I could do this.

I am fairly close to beginning work on my torch now. I just need to complete the pen and then I can do the torch. I am planning on making the torch as well as possible, and incorporating as many different skills as I can in order to make up for not handing in the phone. I haven't really thought of many ideas yet, but there is one that I wouldn't mind trying. I am going to look up how to make a spring, but rather than putting it inside the torch (because in springs in actual torches, the coils slowly become smaller as you move closer to the top, and I think it would be difficult to make it realistic) I want to have the spring design extruded slightly around the surface of the handle of the torch. This could serve to improve aesthetics, and also provide extra grip around the handle for ease of use. I am excited to start work on my torch, and will hopefully begin properly ideating soon.

Starting on ProDesktop

At the start of this week we began working on the CAD program ProDesktop. So far we have mainly been revising things that we learnt last year. These include extruding, protruding, rounding edges and duplicating, along with other basic aspects of the program. The most helpful thing I have learned so far is how to alter extrusions after you have completed them. I did not know how to do this last year and due to this I have occasionally had to restart my work completely because I had extruded the wrong amount. I believe everyone could benefit from knowing how to do this, and as it does not explain how to do it in any of the textbook exercises we have been doing, perhaps Mr Ward could show the class.

Images of the Final Product

This our completed resort. In the last lesson, we made a few final improvements to a couple of different aspects of the resort, like the cabins, dirt and trees, and attached the waterwheel. To do this we used the wire from a pipe cleaner. This involved taking all of the fluff off the pipe cleaner, which took quite a while, but there wasn't any other material we could see that would look as good or work well. It fit well through the center of the wheel and was very easy to bend into shape and glue to the mountain.

I am very happy with how the resort turned out and had a lot of fun making it. Overall, we didn't have many problems creating the resort, and any that we did have were easy to fix. I think that it has come together nicely and looks fairly realistic. All we have left to do in this task is the oral on Friday, but we have already written that so we only have to complete the PowerPoint.