Today, we are going to talk about the graphics tools for engineers. In this course, we are going to look at modern engineering graphics tools in common use, when to use these tools, as well as the difference in their presentation. Well, you can see that these graphics tools for engineers can be roughly divided into three categories. If you have been reading lots of textbooks for engineering graphics, you will find them telling you the same thing: there is freehand drawing by engineers, there is ruler-and-compass construction, and there is CAD, computer-aided drawing. In this course, as we have mentioned before, we will focus more on the freehand drawing and the CAD. Here I am going to show you that in the courses of traditional engineering graphics, we attached great importance to ruler-and-compass construction. This was when I was a student myself, what I learnt about engineering graphics was all ruler-and-compass construction. So ruler-and-compass construction is like this, We have a big drawing table with T-square, to ensure the lines drawn are parallel. There is also the triangle, I think most of you have used this in primary school or secondary school. This triangle, it's a bit longer, it has 30˚, 60˚, 90˚. There is also the 45˚ triangle, that is, we have 90˚, 45˚, 45˚. Then, there is the compass for drawing circles, this special pen, plus this drawing paper. This is a set. In a traditional engineering graphics course, the teacher will ask you to draw on this drawing table with the help of these specialised tools and finish the whole process of drawing here. This was what I was taught when I was in school This is a great picture in my collection. How engineers work back in 1915. I think this looked very smart, you know, with the suit and the vest, and everyone in front of the drawing tables. An engineer came into the office, hung his blazer on the chair and got to work. This is how he worked, he drew, he drew and he drew. So this are the tools for engineers. You can see that they are using the same tools, the triangle, the ruler, etc. and they have a big bag to carry the tools and get the work done. This is a traditional engineer and the ability he required. But after all these years, I don't think the modern engineers need to start from here. Well, this is my personal opinion, and in Department of Civil Engineering of NTU, our teaching emphasis on freehand and CAD too. So you need to come to the understanding that this is what we are going to focus on in this course, we will not put any emphasis on ruler-and-compass construction. If you have special interest in this, you need to find some classic engineering graphics textbooks to learn it yourself. But I think for the current and future engineering demand, what you need is the ability to draw freehand and with computer. And these are our focuses of the course, the skill to draw freehand and with computer. So, today, I will explain briefly which graphics tools are needed by the engineers of today, and the engineers of the future. Well, let me first talk about tools for freehand drawing. The first will be 2D sketching. An engineer must be able to draw a 2D sketch, to express via 2D method. This we will go into details in our next class. 2D sketch, about how to draw circles, squares and gradually, how to combine circles and squares to compose different items in reality. This is a simple example of the sketch. I asked the students in my course to go to the site and draw the buildings freehand. So mostly, this is expressed in 2D, because I asked them to draw the front view, the side view and the back view. Apart from 2D sketch, we also need 3D sketch, that is, to express a 3D structure through sketch. This is a 3D sketch, to express a 3D object from different perspective. Then, apart from freehand drawing, there is the computer drawing. This includes the 2D computer drawing. This is actually just like the 2D sketch I talked about. These are like two sides of the same coin. After you finished with the sketch, you draw it with computer. Just now you’ve drawn the dots, lines and planes with you hand, now you are to express them in computer language. Then, it will be very accurate. You had originally draw a rough form, well, it is usually like that, then, this rough sketch, as you try to draw it with computer program, you will need more accurate information, only after you have all the exact information, you are able to draw a 2D CAD accurately. So this drawing is more precise and more useful in engineering. Then, we will be seeing the 3D CAD. In computer aided drawing, the basic is 2D CAD, it is very easy to learn, the components are quite simple. Basically dots, lines and planes form almost all kinds of engineering graphics. Then, the 3D CAD and 2D CAD, many people thought that's just the difference of an extra D, but that's a huge difference. It is different from the basics. 2D CAD is form by dots, lines and planes; while for 3D CAD, you need to draw the actual 3D structure therefore, this brings the level of accuracy and difficulty of drawing to a whole new level. When I learnt Engineering Graphics, 2D CAD is one course, and you need to take another course to learn 3D CAD. However, nowadays, the tools for Engineering Graphics is becoming simpler and simpler, and 3D CAD is now user-friendly to the majority. Ordinary engineers are able to use such technologies. Here is a good example, this is a 3D drawing. Now, we have a good program, you just need to construct the axis X, Y, Z, draw the 3D structure, and give computer commands about every side, what are their properties, where is the light source, where is the camera, after rendering, the program will produce a very artistic graphic. With the standard of modern engineering tools, it is not so difficult to render very fine 3D graphics. It is even good enough to fool our eyes. That is, if we take a real picture, and one that is rendered by the computer, with the current technology, most of the programs can render a picture that you cannot tell the difference from the real one. So these are the tools we need to know, and also, to use. Then, the next level of difficulty lies with a tool called BIM, Building Information Model or this nD, n dimension tool. This has been developing for quite some time now in the academic circle. It has already started to influence the engineering circle a lot. So the modern engineers should gradually learn nD and the BIM tool This will be another course, so I will not emphasise a lot on this. Anyway, in principle, BIM is Building Information Model. So this is not just the dots, lines and planes and the structure, when you see the graphics produced by BIM, it may seem exactly the same as 2D CAD, but behind this drawing, there is a database. From this database, it will generate a picture according to your angle, your needs in your work, and you can print it out. Though it still looked similar to 2D CAD or 3D CAD, there is an engineering database in this. Now, what good does that do? For example, we change some information in this database, all the graphics, all the relevant graphics will change together. For example, I change the window in this building, all graphics that is related to this window will change. So this is the Engineering Graphics tool that is being developed right now. I believe in the near future, many engineers must learn how to use this tool. In this professional field, if you don't know how to use the tool, it is just like you don't speak the language. Next, there is the animation tool. People may think that, why does an engineer need to learn animation? Isn't that for entertainments? Engineering, as I have mentioned, we need to be able to narrate an incident. The best way to narrate is actually through animation. Whether it is an animation that is showing one frame at a time or a very smooth animation like cartoon, they can both help people to understand how your work is going to proceed as well as the final result of your work. This is a good student example, my postgraduate student made an animation of the hoisting of multicrane. We were helping a petrochemical plant to design the route for large scale hoisting. So how will this large object be hoisted and move through such complicated factory, and eventually reach its final destination? It will be hard to explain this with words or with 2D graphics. There may be a lot of your own assumptions and in reality, it is not what you have imagine. So as we cooperate with some companies, we will express it through videos. So engineers must understand the production of videos. We are all very familiar with videos, that is, movies. Think about what is there in a movie, there is the music, the story, the scenes, the sounds etc. They combined and become something that not only tells us about the incident itself, it echoes in our heart and touches our heart. There are the visual elements in this. Take another good sample, actually, it is a sad example, our team got a case from the Soil and Water Conservation Bureau last year, that is about the Xiao Lin Village, it is the 8th August Storm stimulation video. In this video, we must build a 3D scene and render. We have to show the movement of this 3D scene and describe the whole incident very clearly, the cause and effect, and describe how the storm destroyed the village and killed more than 600 villagers. We describe this incident through story-telling. From the natural rainfall, to mudflow and landslide, up to the miserable ending of burying Xiao Lin Village, the whole description will let us learn our lesson. Such a video, well, we may not say that movie-making is something we as engineers must master, but in the process of producing this video, I discover that. actually, the modern engineers, even the future engineers, should have the ability to produce a video. That is, to show our expertise through a story, to let the public understand. Some may say this does not sound like the work of an engineer. But the reality is, like I am a teacher in engineering field and this is something I do very often. There are also a lot of engineering consulting companies, when they are doing some conceptual design, they realise that, graphics alone, or animation alone, cannot impress the proprietors. They cannot let the proprietors totally understand the concept of their design. So this requires an engineering video to express the concept of the design. So I believe that the future engineers will gradually need to learn how to produce videos, and use it as a way to communicate with the public. Lastly, I will like to add another tool, which may not sound familiar to everyone, the game engines. What is a game engine? It is a 3D virtual world. You can add 3D models in this 3D space, you can also add some physics into it. Such as people walking in there, if they miss their footing, they will fall, such physical phenomenon. In the game engine, we will feel as if we are walking in a real virtual world. There are reactions, such as, if we bump into the wall, we will bounce back etc. Here let me give you an example, this is the game engine we have developed in the past few years in cooperation with University of Washington. This is a game engine to describe engineering accidents and disasters. This is related to engineering. With this game, the workers at the site can really feel the danger of such scenarios, what terrible outcomes these scenarios may cause. Like in this video, the worker is fixing the roof, but because of a wrong move, or a faulty safe-guard, something unfortunate can occur. So the game engine give us real feelings, and through such real sense of danger, we don't need to experience those unfortunate incidents to learn our lessons. We learn some engineering experiences and lessons in games. So, in the field of Engineering Graphics, I think an engineer need to learn this. If we understand such language, it will help us to communicate better. For a short summary, in this course, we will focus on freehand and computer drawing. It is impossible for me to teach everything, but we will emphasise on the 2D sketch and 3D sketch, freehand sketch. Both of them are important. And then, I will teach you 2D CAD and 3D CAD. The point of today's long talk is so that you understand, after we have these bases, we still have quite a lot of tools to learn. Such as 3D CAD, BIM/nD CAD, animation, videos and game engines. I believe in the future, more tools will be developed. All these are ways of communication for engineers. And so, as long as it is needed, let us not limit ourselves on traditional engineering graphics alone and think nothing of the newly developed ways of communication. That will be a great pity. So today, I hope to give you such a spectrum, from the freehand drawing of the early days, to the future development of computer programs. And also, to let you know that, for this course, we will learn the 2D and 3D sketch and 2D CAD. That's all for today's lesson.
