1 00:00:15,746 --> 00:00:18,850 So let's start by talking about 3D printing. 2 00:00:20,225 --> 00:00:22,173 3D printing is a lot like normal printing, 3 00:00:22,173 --> 00:00:24,121 but it's in 3D. 4 00:00:24,121 --> 00:00:26,069 (Laughter) 5 00:00:26,069 --> 00:00:28,139 Not that kind of 3D. 6 00:00:28,237 --> 00:00:29,795 But more like this. 7 00:00:32,519 --> 00:00:36,123 3D printing refers to additive manufactoring techniques 8 00:00:36,639 --> 00:00:38,766 that build objects layer by layer, 9 00:00:39,891 --> 00:00:40,991 starting from nothing 10 00:00:40,991 --> 00:00:43,711 and ending up with a completed physical object. 11 00:00:43,711 --> 00:00:44,925 A common exageration is 12 00:00:44,925 --> 00:00:49,120 a 3D printer is just like a Star Strek replicator, 13 00:00:49,120 --> 00:00:50,287 you can make anything. 14 00:00:50,287 --> 00:00:54,195 Although you can make very complex geometries 15 00:00:54,195 --> 00:00:56,025 with a wide variety of materials 16 00:00:56,025 --> 00:00:58,785 like plastics, powders and metals. 17 00:00:58,785 --> 00:01:01,317 3D printing does have its limitations. 18 00:01:04,248 --> 00:01:06,531 This is why we have so many kinds of 3D printers. 19 00:01:07,156 --> 00:01:10,957 These are a lot of different varieties that exist, 20 00:01:10,957 --> 00:01:13,857 of different kinds of additive manufacturing techniques 21 00:01:13,857 --> 00:01:16,323 that fall within the field of 3D printing. 22 00:01:19,448 --> 00:01:21,393 The true magic of 3D printing 23 00:01:21,393 --> 00:01:23,338 isn't it being a Star Trek replicator. 24 00:01:23,338 --> 00:01:25,283 It's how we use it. 25 00:01:25,853 --> 00:01:28,054 A 3D printer is used by designers 26 00:01:28,054 --> 00:01:30,700 to generate their parts in the real world. 27 00:01:31,119 --> 00:01:32,972 So, you can take a design, 28 00:01:34,215 --> 00:01:37,061 plug it in the printer and it'll print it out for you. 29 00:01:37,061 --> 00:01:38,942 And you can take that part in your hands, 30 00:01:38,942 --> 00:01:41,163 make adjustments to it, change your design 31 00:01:41,163 --> 00:01:42,126 and print another one. 32 00:01:42,126 --> 00:01:43,806 So it's used for iterative design, 33 00:01:44,113 --> 00:01:45,733 and it actually checks parts with the real world. 34 00:01:47,233 --> 00:01:49,063 So it's a really useful tool. 35 00:01:50,819 --> 00:01:54,079 A disadvantage of 3D printing is that it's actually pretty slow. 36 00:01:54,741 --> 00:01:57,291 So we have a really nice little 3D printed cup 37 00:01:57,291 --> 00:02:00,114 over here on the left with an integrated straw. 38 00:02:00,114 --> 00:02:00,954 Pretty cool! 39 00:02:01,664 --> 00:02:04,362 That takes about the same amount of time to print 40 00:02:04,362 --> 00:02:09,352 or to manufacture as these plastic cups 41 00:02:09,352 --> 00:02:12,221 or a hundred packs of 50 plastic cups, so 5,000 plastic cups. 42 00:02:12,958 --> 00:02:14,619 So it's about the same amount of manufacturing time, 43 00:02:14,619 --> 00:02:16,541 That's low-balling it. 44 00:02:17,250 --> 00:02:21,381 So, this layer by layer additive process is pretty slow 45 00:02:22,201 --> 00:02:25,502 compared to a formative manufacturing technique. 46 00:02:27,661 --> 00:02:29,933 So, I started to gain interest in 3D printing, 47 00:02:29,933 --> 00:02:31,635 when I was in my senior year at MIT. 48 00:02:31,635 --> 00:02:34,040 And I wanted to make a printer 49 00:02:34,040 --> 00:02:38,195 that was really fast and really cheap 50 00:02:38,195 --> 00:02:40,525 and printing with a wide variety of materials. 51 00:02:41,095 --> 00:02:43,609 So I was a little disappointed to find out 52 00:02:43,609 --> 00:02:45,571 that these goals were kind of 53 00:02:45,571 --> 00:02:48,123 what the entire 3D printing industry was already working on. 54 00:02:48,123 --> 00:02:49,412 (Laughter) 55 00:02:49,412 --> 00:02:52,428 So, I decided, I needed to take a different approach 56 00:02:52,428 --> 00:02:54,784 if I was going to make a big impact in this field. 57 00:02:56,374 --> 00:02:59,660 So, I kinda looked at the trends that exist within fabrication tools 58 00:02:59,825 --> 00:03:03,765 and you can plot them on this graph here 59 00:03:03,765 --> 00:03:08,379 where the flexibility and speed of a fabrication process 60 00:03:08,379 --> 00:03:10,010 are inversely proportional. 61 00:03:10,010 --> 00:03:14,572 So 3D printing on the left is very flexible, but pretty slow, 62 00:03:14,572 --> 00:03:18,600 and injection molding on the right, making legos is very fast, 63 00:03:18,762 --> 00:03:22,362 but can only make the parts the mold is designed to make. 64 00:03:24,156 --> 00:03:27,546 And I needed something that was both fast and flexible. 65 00:03:27,795 --> 00:03:30,191 Instead of our breakthrough technology 66 00:03:30,191 --> 00:03:33,567 that jumps out of the curve and then I found out 67 00:03:33,567 --> 00:03:37,385 about a little known field called reconfigurable pin tooling, 68 00:03:37,385 --> 00:03:38,886 probably haven't heard of it. 69 00:03:38,886 --> 00:03:43,609 Essentially, the idea is to have a bed of pins 70 00:03:43,609 --> 00:03:46,068 that are adjustable in height 71 00:03:46,068 --> 00:03:47,878 and with those pins, 72 00:03:47,878 --> 00:03:50,636 you can generate a surface for use in molding 73 00:03:50,636 --> 00:03:52,064 or for other applications, 74 00:03:52,064 --> 00:03:54,494 this is from science fiction, this isn't real. 75 00:03:54,764 --> 00:03:56,724 (Laughter) 76 00:03:57,438 --> 00:03:59,798 I was surprised to find out interesting facts though. 77 00:03:59,875 --> 00:04:02,541 This is the first patent in reconfigurable pin tooling, 78 00:04:03,411 --> 00:04:08,107 in 1863, that's 150 years ago. 79 00:04:09,117 --> 00:04:11,055 But in comparison to 3D printing, 80 00:04:11,223 --> 00:04:14,931 the first pattern in 3D printing was in 1984, 81 00:04:14,931 --> 00:04:17,048 that's 29 years ago. 82 00:04:17,558 --> 00:04:24,848 So, if reconfigurable pin tooling is so cool and such an old idea, 83 00:04:25,442 --> 00:04:28,282 why are there no reconfigurable pin tools? 84 00:04:28,573 --> 00:04:33,223 While so many different 3D printers exist on the commercial shelves. 85 00:04:33,403 --> 00:04:36,353 Well, it turns out there are just really hard to make. 86 00:04:37,083 --> 00:04:39,203 So, this is a pin art toy, 87 00:04:39,327 --> 00:04:41,052 you'll probably be familiar with this. 88 00:04:41,052 --> 00:04:43,325 This is the most classic example of a reconfigurable pin tool. 89 00:04:43,325 --> 00:04:46,225 And if I were to make this electronically reconfigurable, 90 00:04:46,565 --> 00:04:50,605 I would have to add a motor to everyone of these pins, right? 91 00:04:50,702 --> 00:04:56,012 And there's about a thousand pins in this sort of cheap desktop toy. 92 00:04:56,264 --> 00:04:58,394 A thousand motors is a lot of motors 93 00:04:58,740 --> 00:05:02,888 and that's a really significant engineering challenge. 94 00:05:05,759 --> 00:05:08,088 You probably or you might have seen this video 95 00:05:08,088 --> 00:05:10,255 which actually came out this last week. 96 00:05:10,815 --> 00:05:15,451 This is a really cool example of a reconfigurable pin display, 97 00:05:15,451 --> 00:05:18,101 that some of my friends made at the MIT media lab. 98 00:05:19,046 --> 00:05:22,188 And this device is individually actuated, 99 00:05:22,188 --> 00:05:26,202 so all the pins have a single motor on each one. 100 00:05:27,306 --> 00:05:30,535 There's 900 pins within 3 inches resolution, 101 00:05:30,535 --> 00:05:33,764 and it was used for haptic interface 102 00:05:33,764 --> 00:05:36,995 and for making experimental services. 103 00:05:38,197 --> 00:05:41,617 So, if I wanted a surface that was high resolution to use as mold, 104 00:05:42,579 --> 00:05:43,829 why can't I do this? 105 00:05:43,829 --> 00:05:47,537 Why can't I make this surface super high resolution? 106 00:05:48,235 --> 00:05:49,915 Math. That's why. 107 00:05:50,392 --> 00:05:51,362 (Laughter) 108 00:05:51,362 --> 00:05:53,552 Math is fighting me on this one. 109 00:05:55,104 --> 00:05:57,095 When I increase the resolution, 110 00:05:57,115 --> 00:06:00,486 I get this quadratic scaling of the area, 111 00:06:00,486 --> 00:06:03,177 so length times width is area, 112 00:06:03,248 --> 00:06:05,578 and that's a nonlinear term. 113 00:06:06,178 --> 00:06:10,038 So, when we get to high resolutions, 114 00:06:10,038 --> 00:06:11,818 this becomes a really big problem. 115 00:06:11,818 --> 00:06:14,189 We get huge numbers of pins to control, 116 00:06:14,189 --> 00:06:15,730 massive numbers of motors 117 00:06:15,730 --> 00:06:17,751 and it just becomes totally unfeasible, 118 00:06:17,751 --> 00:06:19,231 and everything falls apart. 119 00:06:19,727 --> 00:06:21,699 So faced with this hopelesness, 120 00:06:21,699 --> 00:06:25,331 I decided to do this for my PhD and Masters. 121 00:06:25,331 --> 00:06:26,335 (Laughter) 122 00:06:26,674 --> 00:06:28,244 And undergraduate thesis. 123 00:06:30,427 --> 00:06:33,037 And I've been working on it for about 3 years now. 124 00:06:33,684 --> 00:06:36,884 And I've developed a number of techniques 125 00:06:36,884 --> 00:06:40,084 to actuate pins and to move pins. 126 00:06:40,084 --> 00:06:41,766 These are some of the prototypes 127 00:06:41,766 --> 00:06:43,838 and I actually won an award for one of them, 128 00:06:43,838 --> 00:06:45,008 which is the reason I'm here, 129 00:06:45,008 --> 00:06:46,689 because I got picked up after that. 130 00:06:48,038 --> 00:06:51,076 I was kinda disappointed in all of them so far. 131 00:06:51,076 --> 00:06:52,938 Until recently, and that's kinda of 132 00:06:52,938 --> 00:06:55,114 what I wanted to talk to you about today. 133 00:06:55,114 --> 00:06:58,554 So, I had an interesting idea 134 00:06:58,554 --> 00:07:01,024 when I was working on a different project, 135 00:07:01,024 --> 00:07:03,096 not the reconfigurable pin tooling project, 136 00:07:03,187 --> 00:07:05,209 but I was working on a machine 137 00:07:05,209 --> 00:07:07,291 that had a lot of vibrations in it 138 00:07:07,291 --> 00:07:10,725 and what happened is that I was attaching a part to it 139 00:07:11,353 --> 00:07:13,833 and the screws in that part kept on coming loose. 140 00:07:13,833 --> 00:07:16,004 And it was really frustating at first, 141 00:07:16,004 --> 00:07:19,269 but then I realised that I could actually use 142 00:07:19,269 --> 00:07:22,570 this pattern vibration to turn out screws, 143 00:07:22,667 --> 00:07:25,497 which is actually a really good way of getting linear actuation. 144 00:07:25,881 --> 00:07:28,941 So moving something along its axis. 145 00:07:29,530 --> 00:07:34,270 So, what I decided to do is apply this to reconfigurable pin tooling. 146 00:07:35,739 --> 00:07:36,719 And here it is. 147 00:07:37,505 --> 00:07:38,705 It actually works pretty good. 148 00:07:38,705 --> 00:07:40,506 This an array of screws, 149 00:07:41,268 --> 00:07:44,508 that has a specific pattern of vibration applied to it, 150 00:07:46,023 --> 00:07:49,058 and that causes selective screws within the array 151 00:07:49,058 --> 00:07:53,619 to actually turn out and turn them back in as well. 152 00:07:54,267 --> 00:07:55,579 And it works like this: 153 00:07:57,276 --> 00:07:59,751 this is a schematic of the actuaction here. 154 00:07:59,751 --> 00:08:03,468 We have dislocations within the square array of screws 155 00:08:03,468 --> 00:08:05,741 and if you dislocate it just right, 156 00:08:05,777 --> 00:08:08,677 around the screw you want to turn and you reset it, 157 00:08:08,766 --> 00:08:12,466 you get a non linear torque applied to one of the screws, 158 00:08:12,546 --> 00:08:16,046 and you get motion, so pretty cool. 159 00:08:16,334 --> 00:08:19,224 And the coolest thing about this is that the only actuator you need, 160 00:08:19,224 --> 00:08:23,258 the only motor you need for this array is for the edge pieces. 161 00:08:23,258 --> 00:08:26,764 So the edges are always going to scale linearly 162 00:08:26,764 --> 00:08:30,191 with the resolution versus the number of pins scaling 163 00:08:30,191 --> 00:08:32,210 this huge quadratic term. 164 00:08:33,087 --> 00:08:36,070 And all the pins actually are just little screws. 165 00:08:36,070 --> 00:08:37,697 Screws are very cheap, 166 00:08:37,697 --> 00:08:40,039 and you get can cheap linear actuators on the edges 167 00:08:40,039 --> 00:08:41,371 for vibration. 168 00:08:41,371 --> 00:08:44,520 And this works really well at high resolutions 169 00:08:44,520 --> 00:08:46,564 because that ratio becomes higher and higher, 170 00:08:46,564 --> 00:08:48,708 as you get higher in resolution. 171 00:08:48,708 --> 00:08:52,113 The ratio between linear and quadratic terms within the array. 172 00:08:52,113 --> 00:08:53,273 With me so far? 173 00:08:53,273 --> 00:08:55,603 (Laughter) 174 00:08:57,522 --> 00:08:59,990 So, after doing this project, 175 00:09:01,610 --> 00:09:03,256 I'm actually pretty confident 176 00:09:03,256 --> 00:09:06,100 now more so than I have been in the past, 177 00:09:06,100 --> 00:09:09,418 that this HD pin surface could be a reality, 178 00:09:09,418 --> 00:09:11,179 and you could see one of these on your desktop 179 00:09:11,179 --> 00:09:12,920 and download a file into it 180 00:09:12,920 --> 00:09:14,399 and have it reconfigure its surface 181 00:09:14,399 --> 00:09:17,286 into an arbitruary file that you found online 182 00:09:17,318 --> 00:09:22,039 and you use it as a design tool because you could use it as a mold 183 00:09:23,075 --> 00:09:26,047 instead of just 3D printing objects layer by layer 184 00:09:26,047 --> 00:09:28,349 or along with a 3D printer as well. 185 00:09:28,349 --> 00:09:30,615 So, it's really just a close cousin to 3D printing 186 00:09:30,615 --> 00:09:32,161 versus any sort of replacement. 187 00:09:32,161 --> 00:09:34,741 And here it is, this is kind of the pitch, 188 00:09:34,741 --> 00:09:38,311 the digital mold as the next tool 189 00:09:38,311 --> 00:09:44,102 to help form and shape the future of personal fabrication. 190 00:09:44,842 --> 00:09:45,673 That's it. 191 00:09:45,696 --> 00:09:47,536 (Applause)