 We've just seen that 3D printing is changing architecture and it's also changing product and engineering design as well. The first step is through geometric complexity. So for example what you see here on the slide is examples from my first semester mechanical engineering design students who do a customized design project that we 3D print and we 3D printed 1500 design variants over the last three years. We can also think about automating this. So in our work through the combination of artificial intelligence and optimization we can automatically generate such wheels and fabricate them automatically for example in the inline skate that you see here. So 3D printing is really changing our designers and also changing the way that we design. Some people will say complexity is free with 3D printing. I would argue that actually complexity is shifted now upstream to the design process. If this is a 3D printer print bed it has on the order of 10 to the 12th voxels that can be individually designed. If we think about that it's the space is too large for any designer to consider. We also have a 3D printer that prints 40 materials simultaneously. This adds a material dimension as well to the geometry dimension to expand our solution space and create structures that for example vary their elasticity in response to in this case batteries. It could be used for example for shoe insoles or any type of seat. Our vision in my lab is to be able to create a tight coupling between the new design tools that we need to be able to take advantage of the 3D printing processes and the processes themselves including material understanding. And this tight coupling will allow us to really exploit the capabilities here rather than just throw it over the wall to the 3D printer. We focus in our work at the moment on ladder structures because there's an opportunity here to be able to 3D print structures that previously were too costly or too complex to fabricate. Ladder structures are known to be lightweight and we can customize them for the examples that you see in terms of a helmet, a customized implant that you see here for a spinal disc or a ski. In this case of the implant it's a spinal disc implant and we can optimize up to 100,000 elements for the topology of the structure, the material and the geometry so that it fits exactly into the location of the spine and for the patient and we do this in a matter of minutes rather than hours or days. We can also take advantage of the multi-material properties and think about a soft core for the implant to mimic a natural spinal disc or soft inserts into a helmet that customize the helmet and absorb energy impact. So there are many opportunities of the material dimension as well of 3D printing. The next step then is to think about creating active structures. So structures that move after printing and that's the fourth dimension. Here what you see is a range of bistable joints, these joints open and close. You see one open on the left hand side and on the right you see the varying force required to close these. These are monolithically printed, no assembly needed and we can tune them to vary this activation force. In 4D printing what we do is then allow the structures or program the structures to respond to the environment and if we do this they will automatically open or close in response here to temperature. So this is a shape memory polymer that's used to do this and programmed for a certain activation. We can then combine these to create structures that assemble themselves or deploy. Here you see a structure raising up in response to the temperature in the environment and in our case it's load bearing and that's a particular new aspect to our research that these can be really used as functional structures and not just geometries. We can also think about sequencing the actions so we can program these so that the first joint opens then the second and then the third and this will allow us to also achieve multiple states of our structures. And again this is through smart design of the structures, the geometry as well as selection of the materials and that's what's being varied to time the sequence. So going back to our main expertise it's really in the development of computational design tools to be able to design these structures. So we can do it by hand or we create in this case a simulation tool and that tool can generate and simulate all the active states of the structure that you saw being manually deployed on the left hand side. This allows us to design multi-state structures, all these structures are stable in their final state, no energy input is necessary and to really look at the complexity of the space that we can create of these 40 printed or active structures. In order to, I've shown you different capabilities in 3D printing and 4D printing, I'm convinced that in order to really achieve the creativity possible with these techniques through the materials and through the new geometries we must create these computational design methods to move really from simple examples and teaser videos to real applications that are used in industry. Thank you very much.