 Hi everyone. Today me, Ashot Arshanyan and Sergei Kriakosyan are going to be talking about our capstone project, which is modeling, simulating and prototyping well-known mechanisms. We picked six mechanisms and modeled them in a 3D modeling software, SolidWorks, and prototyped them using a 3D printing software and the 3D printer. So our main motivation for this project was to have a physical and visual representation of different physics concepts that we learned during our classes. In my opinion, this would be really helpful for the students as it would be for us too. And also we think that it is very important to have a visual representation of the applications of the concept in this simple mechanism so that it can be projected to more complex ones that we use in real life every day. So the final product of this project is this stand right here. As you can see that includes all six mechanisms as well as their pictures and the description of their motion next to them. But this is not the only deliverable. We have also uploaded all the files publicly to a Github repository that will be shared with all the students that want to experience the same journey. And now we're going to go through every mechanism one by one. So our starting with the first mechanism you can see right here. So this is a rocker lever mechanism with the rotating disk. So as you can see from the diagram, so there are two cranks, this one and four. The crank one is rotating evenly around the fixed axis. And there's also the guiding fixed piston pipe which is moving in the rails of the rod too. And the main property of this mechanism is that this P4 is rotating on the disk and it's going to the inner and outer radius of the disk to this rails. So the main applications of this mechanism are the windshield wiper project and quick return mechanism. These are just some examples. There are a lot of applications for this and as you can see from the for these two pictures. So here's the path of the crank one and the path of crank four. As you can see the crank four is not making the uniform circular motion. And here on the graphs you can see that the velocity along the y-axis which is the upwards axis and the velocity this is the for the P4. So and the velocity along the z-axis which is along the mechanism main part. And as you can see it is not uniform and the maximum velocity is achieved in y-axis achieved in this part of the movement and along the z-direction during the bottom and the top part of the disk. So going to the next mechanism it's the mechanism of the anti-parallelogram with trailed road and slide. This is also a piston mechanism. It needs to satisfy some conditions like AD equals DC and BC equals AD. Right here as you can see AD, CD, DD and AD does creating the anti-parallelogram ABCD. There are two main roads CD and AD as mentioned and the lower one rotates 360 degrees while the upper one only does 180 degree rotation. This is done to make the piston move unevenly which is basically the application of this mechanism. The roads are connected with the solid road BC which also makes the piston move unevenly. This mechanism has this claw-looking parts at the point G and H which is used to limit the motion of the road BC. However in our implementation we used this motion limiter right here and right here as you can see to limit the motion of the upper road to make the piston move unevenly. This is by the way our modeling of the mechanism in solid works and some of the applications of such mechanism can be two-stroke engines or scroll compressors basically anything that any technology that uses pumps and we also extracted the paths of the roads that I mentioned from solid works and you can see the full circle rotation and the half circle rotation as well as from the graphs of the piston they show the velocity of the piston you can see that the velocity is not uniform meaning that the piston does move unevenly and the highest velocity is achieved when the piston is somewhere in the middle. The reason why this gap is so long is we made it so that it's possible for the piston to do the motion in the reverse direction we would just need to put the piston in the right part. So the next mechanism is the crank slider hammer mechanism A with the elastic link so as you can see from the diagram the crank one is revolving around the fixed axis A and the slider two which is also the hammer is going up and down in the fixed guides A here and they are connected with the elastic link three so elastic link here plays a role of a suspension so that if the if this part would be solid the mechanism would break if the object here for example would be too big but in this way we are preventing from doing that so the main application of this mechanism are the dynamic analysis and testing of different materials and structures so that the impact flow can be applied on the objects and the results can be measured also a great way to optimize this mechanism is to use the piezoelectric actuators which would convert the electrical impulses into the deformations and it would change the property of the elastic link and it would change the the kind of measurements that we get from when the impact load is applied on different objects. The next mechanism is very similar to the previous one called Crank Slider Hammer Mechanism B with an elastic link this has all the same applications as the previous mechanism this is the previous one and this is the one I'm talking about right now the main difference is that the elastic link is different in the previous one it's a spring and in this one is this is a same flexible sheet metal we wanted to include both of the mechanism to showcase the different types of elastic links so the next mechanism right here so this is the punching cum machine which you can see there is a cum here with two profiles AA and it's rotating around the fixed axis and it's moving up the PNC which is connected rigidly with this part which is the rod one and also the hammer at the bottom so yeah this mechanism is used to convert the rotating motion into the linear motion and in our case the linear motion is used to again either to punch or stamp or to deformate objects underneath so and these are the applications some of them are like stamping machine that may be used to stamp pages or coins and the forming mechanism that can deform any object that is located underneath and the sixth mechanism is called three link how mechanism of punching hammer in this mechanism cam one which is right here and this part right here rotates around the fixed axis a and pushes the roller five down which makes the main road three go up and down and puncture the product that is put underneath it it can be metal or no metal we added a spring to the main road three to make it go back up after the cam one is not in touch with the roller anymore the the main road will just go up and wait for the cam to come back and push it down again and that's complete the cycle applications of these mechanisms can be in automotive engines textile machinery the mechanism itself looks like a sewing machine and that's mainly about the mechanism themselves talking about the physical environment the stand is planned to be put in one of a way labs to be showcased for the students car incidents and future they are the mechanism and the stand is plan to perform under normal conditions and should not be damaged in room temperature with normal appliance to however students are are in car is not to apply excessive amount of pressure to the mechanism to avoid breakage however they can guide with one hand to put that the mechanism and do the motion so that the mechanism doesn't bend or it's used we use the double sided tape to tape it down to the stand so that it doesn't break or anything and some potential issues with the 3d printed parts is the accuracy of their design so since the 3d printing the technology is working in a way of depositing the layers of material on top of each other this may cause some parts to warp or to be misaligned and yeah this can lead to bad performance or mechanisms failure and also it is because of that it is a bit difficult to produce the 3d printed parts with tight tolerance we actually had this problem during the printing and assembling that the offices that we made were not enough and we did some amount of physical work needed to be done with the 3d printed parts so that they can fit into each other so this is mainly it as we mentioned before that every file that we used for our modeling is uploaded publicly to github everyone can have access to it we can provide the link and everything so that students can reprint the parts again and or look at the models and get acquainted with them more thank you very much I wanted to say if I would do a science museum I would buy this from you guys and probably order more that's the idea and this is the message to the next cohorts of engineering students if they want to continue there is a big plan okay just question one question do you think this size and this setup that we have made can be actually motorized with small motors so that you can like visually can press a button and you can start moving and you see how it works or it will not work because of the like all the problems that you mentioned yeah yeah so yeah actually we there was a idea initially to have the motors also with it but yeah as we mentioned with the 3d printed parts it's a bit because of the high friction and between the parts it's pretty hard to do that but yeah I think we had a plan issue we just yeah if I can just to follow up comments so somewhere in between a real motor and real parts on one extreme and on the other extreme a lot of text and eloquent presentation there's probably a place in a presentation like this for a video or animation or something so you don't have to explain point eight a point they rotate move up on picture I mean just some of those videos are worth a thousand pictures right I mean something to shorten so you can get to the substance more to just show think this is a perfect topic to do it some kind of demonstration if a real demonstration is or the challenging for those reasons I bet you can even find a stock video of any of these things work yeah actually we yeah we actually animated them in the solid in solid works but in the first mechanics when you were showing the first one you there was a slide telling what the applications I think you missed for the others or very few that's very important it's a very close yeah I mean here no it was here too maybe one briefly yeah yeah we try to include some applications for that that's the most important for students and for everyone to understand okay I understand what it does but why yeah the main idea was that so that it they understand how it is used in the complex mechanics that are used like every day so because all this is like internal combustion engines and everything that all this is used there so that's why yeah no I think yeah everything was included well I have two technical questions actually one of them is kind of a follow-up questions of the previous ones so as a zero of estimation based on what you learn throughout this project what would you say which mechanism out of the six would break break down the first you'd have the shortest life last longest longest life this one the first one would definitely last the longest because as you can see is the biggest one with the dimensions comparatively this was our first try and as you can see somewhere here we super glued it together because the components were too big for the printer to print in one go that's why we just super glue them together on two goes so this would last the longest I believe this would break first if it had to break because the you know the parts are miniature I believe more fragile than others but if we're talking about applying the excessive amount of force I believe if we added a spring here which there is an opportunity because this mechanism can be deassembled and we can add a spring and diagram it was like that so we assemble it back and if the spring has a lot of stiffness when we will do this for the mechanism to work I believe this does have some threshold after which it's really good that you guys have an impression if you want to do more tests to have more quantitative analysis of it it's really good that you know where to start from my second question is regarding the acceleration and the velocity graphs what's the message you trying to tell me by showing those graphs like or let me rephrase the question if you remove those graphs what would I be missing what kind of information I would be missing with those graphs we try to prove that the mechanism the motion that we try to achieve we did achieve with the for example with the uneven unevenly moving piston is we try to show that the piston indeed does move unevenly when and in the real life we did achieve that motion as well and in the 3D modeling software but you could tell me the same information as you just did with writing text so what's the for example also difference if you remove that graph and explain this in a single sentence so why shouldn't get in the graph I think that for the mechanism where we showed the graph is just visually even in the software works it's not quite visible the concept that we are trying to represent that's why we included it there again like to prove that actually it's like that because another mechanism is like nothing to show that that is not visible so