WEBVTT 00:00:00.095 --> 00:00:02.470 The following content is provided under a Creative 00:00:02.470 --> 00:00:03.880 Commons license. 00:00:03.880 --> 00:00:06.920 Your support will help MIT OpenCourseWare continue to 00:00:06.920 --> 00:00:10.570 offer high-quality educational resources for free. 00:00:10.570 --> 00:00:13.470 To make a donation or view additional materials from 00:00:13.470 --> 00:00:17.400 hundreds of MIT courses, visit MIT OpenCourseWare at 00:00:17.400 --> 00:00:18.650 ocw.mit.edu. 00:00:28.750 --> 00:00:32.270 PROFESSOR: As it turns out, not by coincidence, the Apollo 00:00:32.270 --> 00:00:35.950 program that started after Kennedy's speech was made up 00:00:35.950 --> 00:00:38.270 of a few different elements of things that had been sort of 00:00:38.270 --> 00:00:40.590 percolating in the background. 00:00:40.590 --> 00:00:44.490 And one of them was studies at MIT on guidance, not so much 00:00:44.490 --> 00:00:48.290 to the Moon, but to Mars, and coming out of Draper's 00:00:48.290 --> 00:00:48.960 laboratories. 00:00:48.960 --> 00:00:53.290 So I wanted to say a little bit about that story, because 00:00:53.290 --> 00:00:54.290 it's an interesting story. 00:00:54.290 --> 00:00:55.970 And it's one you may not have seen quite in this way. 00:00:55.970 --> 00:00:58.530 So what we've talked about before and the inertial 00:00:58.530 --> 00:01:00.150 guidance and all that sort of stuff. 00:01:00.150 --> 00:01:03.990 This is the sort of very clearly posed paradigmatic 00:01:03.990 --> 00:01:05.240 picture of him. 00:01:07.900 --> 00:01:10.510 And during the Second World War, they started making these 00:01:10.510 --> 00:01:11.010 gun sights. 00:01:11.010 --> 00:01:12.860 And one of them was called Doc's Shoebox. 00:01:12.860 --> 00:01:15.320 And then I think we talked about that too, which allowed 00:01:15.320 --> 00:01:16.930 him to sort of lead the target. 00:01:16.930 --> 00:01:20.300 You can actually see, if you go into the front door of 00:01:20.300 --> 00:01:23.190 Draper Laboratories, they have this prototype that he built 00:01:23.190 --> 00:01:26.740 in his garage, sitting there. 00:01:26.740 --> 00:01:28.610 And then during the war, as we talked about-- 00:01:28.610 --> 00:01:32.590 sorry, during the Cold War, they built a lot of 00:01:32.590 --> 00:01:33.380 different kinds of-- 00:01:33.380 --> 00:01:34.740 I'm going to skip through these-- 00:01:34.740 --> 00:01:37.570 inertial guidance and stuff, particularly 00:01:37.570 --> 00:01:39.210 for ballistic missiles. 00:01:39.210 --> 00:01:44.155 And a bunch of these guys, including this guy here, Dick 00:01:44.155 --> 00:01:49.190 Batten, really did some fundamental work in the theory 00:01:49.190 --> 00:01:51.740 of inertia guidance. 00:01:51.740 --> 00:01:55.980 It was pretty much literally how do I get a nuclear missile 00:01:55.980 --> 00:01:59.850 to land on a Russian city, given the gravity field of the 00:01:59.850 --> 00:02:02.260 Earth is not uniform, and there's a lot of calculations, 00:02:02.260 --> 00:02:04.650 and we don't have a lot of different things? 00:02:04.650 --> 00:02:06.210 And then this group-- 00:02:06.210 --> 00:02:09.430 the guy on the left, his name is Hal Laning and he was a 00:02:09.430 --> 00:02:11.630 computer guy from the Whirlwind group. 00:02:11.630 --> 00:02:15.490 Milt Trageser is the guy in the back there and Dick Batten 00:02:15.490 --> 00:02:16.190 is on the right. 00:02:16.190 --> 00:02:19.560 Batten actually still teaches a course in Core 16 on 00:02:19.560 --> 00:02:20.940 astronomical guidance. 00:02:20.940 --> 00:02:23.000 Actually, he may not have taught it this year. 00:02:23.000 --> 00:02:24.450 That's more or less a course he's been teaching 00:02:24.450 --> 00:02:29.060 continuously since 1945 or so, 1946. 00:02:29.060 --> 00:02:33.360 And if you've ever seen when they send a probe-- actually 00:02:33.360 --> 00:02:37.390 they just did this with the Messenger probe to Mercury-- 00:02:37.390 --> 00:02:43.040 and then they sort of swing it around another planet as a way 00:02:43.040 --> 00:02:45.690 to get it accelerated toward its goal, as opposed to just 00:02:45.690 --> 00:02:47.635 sending it directly there, that's actually an idea that 00:02:47.635 --> 00:02:49.110 Batten invented. 00:02:49.110 --> 00:02:53.010 It is now used commonly in all these different space probes. 00:02:53.010 --> 00:02:55.040 And they made this Mars probe. 00:02:55.040 --> 00:02:57.740 And the idea behind this probe was to go to Mars, take one 00:02:57.740 --> 00:03:00.630 picture, and come back to the Earth and reenter 00:03:00.630 --> 00:03:01.890 and drop the film. 00:03:01.890 --> 00:03:05.130 And this thing, which looks just like the Mercury capsule, 00:03:05.130 --> 00:03:06.740 is the film canister. 00:03:09.560 --> 00:03:13.590 And they had also in the '50s, they built the guidance system 00:03:13.590 --> 00:03:17.080 for the Polaris missile. 00:03:17.080 --> 00:03:19.630 And the important thing about the Polaris missile is it was 00:03:19.630 --> 00:03:21.890 the first missile that could be launched out of a 00:03:21.890 --> 00:03:24.210 submarine, out of the Polaris submarine. 00:03:24.210 --> 00:03:29.640 And was a major US, huge project during the '50s. 00:03:29.640 --> 00:03:34.110 And basically they wrote a very short proposal, proposing 00:03:34.110 --> 00:03:38.150 to use that guidance system to go to the Moon. 00:03:38.150 --> 00:03:41.730 And they were awarded a contract August 4, I believe 00:03:41.730 --> 00:03:43.120 it was, 1961. 00:03:43.120 --> 00:03:46.100 It was the first contract of the entire Apollo program and 00:03:46.100 --> 00:03:47.350 it came to MIT. 00:03:49.890 --> 00:03:54.920 Which is some indicator a, of how important they considered 00:03:54.920 --> 00:03:55.570 the guidance. 00:03:55.570 --> 00:03:58.070 Like how do you get there and how you keep from smashing 00:03:58.070 --> 00:03:59.360 into the Moon, and how do you get home and keep from 00:03:59.360 --> 00:04:02.010 smashing into the Earth when you get home? 00:04:02.010 --> 00:04:07.800 And b, it was the only major contract of the entire program 00:04:07.800 --> 00:04:09.290 that was awarded to a university, 00:04:09.290 --> 00:04:11.940 and not to a company. 00:04:11.940 --> 00:04:14.250 And of course, the president was from Massachusetts. 00:04:18.570 --> 00:04:20.790 One of the very senior technical people, Bob Siemens, 00:04:20.790 --> 00:04:23.040 was an MIT guy, a student of Draper's. 00:04:23.040 --> 00:04:25.560 He was essentially the chief engineer at this point. 00:04:25.560 --> 00:04:28.710 And a little bit like the Radiation Lab, there's no 00:04:28.710 --> 00:04:33.980 question that those influences helped steer this contract, 00:04:33.980 --> 00:04:35.580 which was a lot of money. 00:04:35.580 --> 00:04:37.520 Although it was less significant for the money in 00:04:37.520 --> 00:04:39.050 some sense, than for the prestige that 00:04:39.050 --> 00:04:40.020 went along with it. 00:04:40.020 --> 00:04:41.420 And it was sole source. 00:04:41.420 --> 00:04:42.370 There was no competition. 00:04:42.370 --> 00:04:43.260 There was no proposals. 00:04:43.260 --> 00:04:44.840 It just came straight MIT. 00:04:44.840 --> 00:04:48.760 And all kinds of companies protested it to Congress. 00:04:48.760 --> 00:04:51.120 And it turned out it was fully legal, so they 00:04:51.120 --> 00:04:54.920 never changed it. 00:04:54.920 --> 00:04:56.760 But it was not for a computer, actually. 00:04:56.760 --> 00:04:59.360 It was just for this guidance unit and it was over the 00:04:59.360 --> 00:05:00.420 course of the project. 00:05:00.420 --> 00:05:09.070 And remember, this is 1961 and all they thought about was how 00:05:09.070 --> 00:05:10.620 do we get there and back? 00:05:10.620 --> 00:05:15.560 And they begin working on this problem in seven years or so. 00:05:15.560 --> 00:05:17.520 And the idea was that the astronaut would 00:05:17.520 --> 00:05:19.290 sit inside the capsule. 00:05:19.290 --> 00:05:25.180 And if you looked at the stars with the telescope, you could 00:05:25.180 --> 00:05:29.000 basically align yourself and align the inertia platform. 00:05:29.000 --> 00:05:32.580 Remember the inertial platform navigates with accelerometers, 00:05:32.580 --> 00:05:33.940 which can be very accurate. 00:05:33.940 --> 00:05:37.300 But what's problem with doing that? 00:05:37.300 --> 00:05:38.860 It drifts. 00:05:38.860 --> 00:05:41.370 So it loses its absolute accuracy over time. 00:05:41.370 --> 00:05:44.610 So every once in while, you have to realign it and retell 00:05:44.610 --> 00:05:45.480 it where it is. 00:05:45.480 --> 00:05:49.280 And you could align yourself by just pointing at the stars 00:05:49.280 --> 00:05:51.380 and knowing which way is up, in what's 00:05:51.380 --> 00:05:53.880 called an inertial frame. 00:05:53.880 --> 00:05:57.280 But if you wanted to actually navigate, you had to do things 00:05:57.280 --> 00:05:58.690 or closer to the planet. 00:05:58.690 --> 00:06:00.240 So you could look at particular 00:06:00.240 --> 00:06:02.110 points on the Earth. 00:06:02.110 --> 00:06:04.810 The obvious one, the easiest one is measure the size of the 00:06:04.810 --> 00:06:06.610 Earth, because as you go further 00:06:06.610 --> 00:06:07.365 away, it get's smaller. 00:06:07.365 --> 00:06:09.620 It turns out that's not a very accurate measurement. 00:06:09.620 --> 00:06:12.100 But it is one way to measure where you are. 00:06:12.100 --> 00:06:15.610 The most accurate way to measure it is star 00:06:15.610 --> 00:06:16.070 occultation. 00:06:16.070 --> 00:06:19.270 So that if there's a star that passes by the horizon, you 00:06:19.270 --> 00:06:22.650 note the timing of that star and that gives you a very good 00:06:22.650 --> 00:06:23.790 sense of where you are. 00:06:23.790 --> 00:06:26.470 So there's a whole variety of things-- is anybody into 00:06:26.470 --> 00:06:29.160 astronomy here? 00:06:29.160 --> 00:06:30.230 I never was particularly. 00:06:30.230 --> 00:06:32.670 But last year, my brother brought me a telescope that 00:06:32.670 --> 00:06:35.120 has one of these motorized mounts on it, where you can 00:06:35.120 --> 00:06:37.270 sort of tell it what star it is and it'll go there. 00:06:37.270 --> 00:06:40.770 That's basically what the Apollo guidance computer was, 00:06:40.770 --> 00:06:42.990 where it would point out different stars. 00:06:42.990 --> 00:06:44.500 It had a little database. 00:06:44.500 --> 00:06:47.580 And the database of stars that was used in the entire Apollo 00:06:47.580 --> 00:06:50.710 program was, I forget, something like 100 stars long. 00:06:50.710 --> 00:06:54.230 And it was one junior engineer in 1962, came to the MIT 00:06:54.230 --> 00:06:56.990 libraries and looked up all the star coordinates and put 00:06:56.990 --> 00:06:57.650 them in the computer. 00:06:57.650 --> 00:07:00.760 And that's the one they used all the way through. 00:07:00.760 --> 00:07:03.850 And astronauts were then trained to know which stars, 00:07:03.850 --> 00:07:05.610 and they each had a number on them, and they could align 00:07:05.610 --> 00:07:10.460 themselves with the catalog and make sure they were 00:07:10.460 --> 00:07:12.040 getting there. 00:07:12.040 --> 00:07:15.900 And eventually, they ended up putting a digital computer in 00:07:15.900 --> 00:07:18.900 it, which was a pretty radical step at the time. 00:07:18.900 --> 00:07:21.990 Because again, computers were room-size things. 00:07:21.990 --> 00:07:25.080 And this was a computer that was briefcase size. 00:07:25.080 --> 00:07:27.540 And for those of you who are into computers, it looked a 00:07:27.540 --> 00:07:30.570 lot more like a microcontroller than a 00:07:30.570 --> 00:07:32.470 full-up, general purpose computer. 00:07:32.470 --> 00:07:36.680 It was modest numerical capability, but lots of I/O 00:07:36.680 --> 00:07:40.530 and interrupts and things going in and out, 16 bits. 00:07:40.530 --> 00:07:43.440 And it wasn't actually a single chip thing, like a 00:07:43.440 --> 00:07:45.810 microcontroller today, but it had a lot of those 00:07:45.810 --> 00:07:51.000 characteristics, including this interface for the crew. 00:07:51.000 --> 00:07:53.580 And it tied into the inertial system. 00:07:53.580 --> 00:07:56.560 So you have this combination of the gyroscopes, the 00:07:56.560 --> 00:08:01.180 telescopes, the computer itself, and this display 00:08:01.180 --> 00:08:03.560 keyboard unit. 00:08:03.560 --> 00:08:06.620 And this is-- 00:08:06.620 --> 00:08:08.870 actually I forget who this is. 00:08:08.870 --> 00:08:10.790 I think it's Jim Lovell. 00:08:10.790 --> 00:08:12.360 No, Jim Lovell's the next one. 00:08:12.360 --> 00:08:15.170 One of the Apollo astronauts operating this system. 00:08:15.170 --> 00:08:19.290 And there would have been a display keyboard like that, up 00:08:19.290 --> 00:08:22.480 on the main console, which he's looking at, you can see 00:08:22.480 --> 00:08:23.320 at the top. 00:08:23.320 --> 00:08:24.080 I don't know if you're familiar. 00:08:24.080 --> 00:08:27.430 Has anybody seen the Apollo capsules down in the 00:08:27.430 --> 00:08:31.080 Smithsonian Air and Space Museum? 00:08:31.080 --> 00:08:32.500 They looked very awkward on Earth. 00:08:32.500 --> 00:08:35.580 But they were easier in space, where when they're launching, 00:08:35.580 --> 00:08:38.220 this guy, he would be in the launch position, and have his 00:08:38.220 --> 00:08:41.470 back on the ground, looking at this control panel. 00:08:41.470 --> 00:08:43.539 And then when they get into space, he 00:08:43.539 --> 00:08:45.080 actually can move up here. 00:08:45.080 --> 00:08:48.460 And this is actually 90 degrees from that position. 00:08:48.460 --> 00:08:51.300 And there's a whole station where they navigate from. 00:08:51.300 --> 00:08:57.420 And what they would do would be navigate by-- 00:08:57.420 --> 00:09:00.140 again, they're not flying the spaceship doing this. 00:09:00.140 --> 00:09:02.750 They're just aligning the inertial system. 00:09:02.750 --> 00:09:08.340 And then once the inertial system knows where it's going, 00:09:08.340 --> 00:09:11.160 they type in where they want to go on the keyboard. 00:09:11.160 --> 00:09:16.930 And so every few hours or so, the inertial system would need 00:09:16.930 --> 00:09:17.690 to be realigned. 00:09:17.690 --> 00:09:20.620 So it would point at where it thinks the star was. 00:09:20.620 --> 00:09:22.660 The astronaut would look through these telescopes. 00:09:22.660 --> 00:09:25.360 One was a sort of low power, for getting the thing in the 00:09:25.360 --> 00:09:25.910 field of view. 00:09:25.910 --> 00:09:28.300 And one was a high power, for the precision pointing. 00:09:28.300 --> 00:09:30.120 And then he had these two little sets of 00:09:30.120 --> 00:09:31.390 toggle switches here. 00:09:31.390 --> 00:09:35.840 One of them would just move the mirror in one axis and the 00:09:35.840 --> 00:09:37.830 other would actually rotate the spacecraft around. 00:09:37.830 --> 00:09:41.330 And between those two things, they would realign the star. 00:09:41.330 --> 00:09:43.600 It would usually be off center, just a little bit. 00:09:43.600 --> 00:09:45.100 And they would say no, that's not where it should be. 00:09:45.100 --> 00:09:46.390 It should be here. 00:09:46.390 --> 00:09:48.790 And then enter it into the computer 00:09:48.790 --> 00:09:49.860 and say that's centered. 00:09:49.860 --> 00:09:52.550 And the computer would take those error corrections, in 00:09:52.550 --> 00:09:54.080 what today we call a common filter-- 00:09:54.080 --> 00:09:55.130 Batten was one of the inventors 00:09:55.130 --> 00:09:57.180 of the common filter-- 00:09:57.180 --> 00:09:59.835 and then update its guidance solution. 00:09:59.835 --> 00:10:04.120 It turned out you could do that very accurately in 00:10:04.120 --> 00:10:05.270 getting to the Moon. 00:10:05.270 --> 00:10:08.880 And in Apollo 8, this is Jim Lovell, who is probably best 00:10:08.880 --> 00:10:12.480 known for his commanding of Apollo 13, a few years later. 00:10:12.480 --> 00:10:14.490 But this is Apollo 8, where they first flew to the Moon. 00:10:14.490 --> 00:10:15.900 And here you can see him doing it. 00:10:15.900 --> 00:10:18.690 And there's the keyboard unit up there. 00:10:18.690 --> 00:10:21.950 And there was essentially no real hands-on of the joystick, 00:10:21.950 --> 00:10:23.290 flying to the Moon. 00:10:23.290 --> 00:10:25.850 It was much more OK, we've got our unit aligned. 00:10:25.850 --> 00:10:29.300 He did this 200 times over the course of the trip to and from 00:10:29.300 --> 00:10:30.810 the Moon on Apollo 8. 00:10:30.810 --> 00:10:34.170 This is where they orbited, but they never landed. 00:10:34.170 --> 00:10:41.440 And he realigned it 200 times. 00:10:41.440 --> 00:10:43.790 It had very, very accurate navigation. 00:10:43.790 --> 00:10:46.600 And the rest of it would be OK, here's where we want to 00:10:46.600 --> 00:10:48.920 go, here's the velocity we want to achieve. 00:10:48.920 --> 00:10:52.330 And the computer would just orient the spacecraft, set up 00:10:52.330 --> 00:10:54.880 the big thruster to fire, fire it, and then have the big 00:10:54.880 --> 00:10:56.720 velocity change. 00:10:56.720 --> 00:10:59.280 A bit change in how the astronauts expected 00:10:59.280 --> 00:11:00.606 to fly to the Moon. 00:11:00.606 --> 00:11:01.538 Yeah, Sarah? 00:11:01.538 --> 00:11:03.402 AUDIENCE: Is that a picture of the Command Module or the 00:11:03.402 --> 00:11:04.340 [INAUDIBLE]? 00:11:04.340 --> 00:11:06.180 PROFESSOR: This is in the Command Module, actually. 00:11:06.180 --> 00:11:08.220 AUDIENCE: So there was a DSKY in both? 00:11:08.220 --> 00:11:10.330 PROFESSOR: There was a DSKY in both, yes. 00:11:10.330 --> 00:11:12.720 So there were two identical copies of the computer, one 00:11:12.720 --> 00:11:16.230 was in the Lunar Module and one was in the Command Module. 00:11:16.230 --> 00:11:19.100 They had different software running on them though. 00:11:19.100 --> 00:11:25.170 And in Apollo 13, that turned out to be a huge benefit 00:11:25.170 --> 00:11:28.680 because they could shut the entire Command Module down and 00:11:28.680 --> 00:11:37.670 transfer the coordinates from one to the other and keep the 00:11:37.670 --> 00:11:40.780 inertial solution of where they were in the Lunar Module, 00:11:40.780 --> 00:11:42.370 while they powered down. 00:11:42.370 --> 00:11:45.460 So they had a redundant system without really what being 00:11:45.460 --> 00:11:47.780 aware of it, in a certain way, without planning it, although 00:11:47.780 --> 00:11:49.520 they did sort of plan it. 00:11:49.520 --> 00:11:51.690 And the interesting thing is these were two separate 00:11:51.690 --> 00:11:52.410 spacecrafts. 00:11:52.410 --> 00:11:53.830 How would you do that today? 00:11:53.830 --> 00:11:57.220 Well, you'd have some network and you just say, copy the 00:11:57.220 --> 00:11:58.080 coordinates over. 00:11:58.080 --> 00:12:00.290 And all they could do there was read it off the LED 00:12:00.290 --> 00:12:03.820 display and yell it down the tunnel. 00:12:03.820 --> 00:12:05.700 And the other guy would type it in. 00:12:05.700 --> 00:12:06.700 There was no electrical 00:12:06.700 --> 00:12:07.990 connection between two computers. 00:12:12.680 --> 00:12:16.610 This is actually-- the picture in the MIT Museum, behind the 00:12:16.610 --> 00:12:19.350 prototype of the computer that's sitting there. 00:12:19.350 --> 00:12:21.840 It's Davey Hoag, one of the engineers on it, just another 00:12:21.840 --> 00:12:22.620 view of it. 00:12:22.620 --> 00:12:24.880 Although it's a very interesting thing here, this 00:12:24.880 --> 00:12:28.530 was the original block 1 version of the computer. 00:12:28.530 --> 00:12:30.520 And the idea was the astronauts would be able to 00:12:30.520 --> 00:12:32.500 repair the computer in flight. 00:12:32.500 --> 00:12:35.470 And it's sort of like, anybody ever have an old IBM PC where 00:12:35.470 --> 00:12:36.080 you could pull-- 00:12:36.080 --> 00:12:37.870 I guess PCs are still this way. 00:12:37.870 --> 00:12:39.950 You can pull the cards out and put new 00:12:39.950 --> 00:12:41.180 cards in them and stuff. 00:12:41.180 --> 00:12:42.100 That was the idea here. 00:12:42.100 --> 00:12:44.430 You'd be able to pull the cards out. 00:12:44.430 --> 00:12:46.790 And they actually talked about the astronauts having tools 00:12:46.790 --> 00:12:49.060 and soldering irons and things to repair 00:12:49.060 --> 00:12:51.750 the computer in flight. 00:12:51.750 --> 00:12:57.220 That turned out to be a bad idea because on a space 00:12:57.220 --> 00:13:00.360 flight, and this is still true today, the physical 00:13:00.360 --> 00:13:03.180 environment becomes completely contaminated with all of the 00:13:03.180 --> 00:13:05.880 exhalations from the human bodies. 00:13:05.880 --> 00:13:09.880 And on one of the Mercury flights, one of the 00:13:09.880 --> 00:13:11.840 electronics boxes shorted out. 00:13:11.840 --> 00:13:16.050 And it turned out there were urine crystals from the 00:13:16.050 --> 00:13:18.070 astronaut that had-- 00:13:18.070 --> 00:13:21.140 it was vapor I guess, that had crystallized on the circuits 00:13:21.140 --> 00:13:22.020 and shorted them out. 00:13:22.020 --> 00:13:25.990 And so after this, they ended up going away from this 00:13:25.990 --> 00:13:28.640 in-flight repair and just building one sealed box that 00:13:28.640 --> 00:13:31.270 was completely hermetically sealed, no possibility of 00:13:31.270 --> 00:13:32.240 repairing it. 00:13:32.240 --> 00:13:34.670 And how did they have redundancy you might ask? 00:13:34.670 --> 00:13:35.760 And the answer is they didn't. 00:13:35.760 --> 00:13:37.840 They just tried to engineer it really well, to 00:13:37.840 --> 00:13:41.050 make it really reliable. 00:13:41.050 --> 00:13:44.520 Anybody know how many on the Space Shuttle to control it? 00:13:44.520 --> 00:13:46.170 Five. 00:13:46.170 --> 00:13:47.950 Five parallel redundant computers. 00:13:47.950 --> 00:13:49.525 There's one in the Apollo system. 00:13:49.525 --> 00:13:51.356 It never failed in flight. 00:13:54.500 --> 00:13:56.670 This is another view of that process. 00:14:02.160 --> 00:14:06.730 Here's where the astronaut in the Command Module can look at 00:14:06.730 --> 00:14:08.630 the Lunar Module and they can navigate 00:14:08.630 --> 00:14:09.980 relative to each other. 00:14:09.980 --> 00:14:12.310 So you could think in your mind about all the different 00:14:12.310 --> 00:14:15.790 possible combinations of looking at the Command Module, 00:14:15.790 --> 00:14:18.090 looking at the Lunar Module, looking at the Earth, a 00:14:18.090 --> 00:14:19.380 million different things you can do. 00:14:19.380 --> 00:14:23.270 And it was an supremely flexible program 00:14:23.270 --> 00:14:25.630 that they could use. 00:14:25.630 --> 00:14:26.880 Here's another view. 00:14:30.400 --> 00:14:31.930 I probably just like the way they make these 00:14:31.930 --> 00:14:32.680 drawings and stuff. 00:14:32.680 --> 00:14:35.420 And you can see in all of them, made by the computer 00:14:35.420 --> 00:14:38.120 engineers at Draper, with computers in the center of the 00:14:38.120 --> 00:14:40.840 system and the astronaut is like this minor peripheral 00:14:40.840 --> 00:14:43.360 that contributes something here and there. 00:14:46.510 --> 00:14:49.450 Here's another one, yet another one. 00:14:52.270 --> 00:14:54.970 This is actually a view that's kind of interesting to look 00:14:54.970 --> 00:15:03.350 at, of the position error at the critical moment where they 00:15:03.350 --> 00:15:06.920 left the Earth's gravitational field and they entered the 00:15:06.920 --> 00:15:08.690 Moon's gravitational field. 00:15:08.690 --> 00:15:14.190 And when they're sighting on the Earth's horizon as they 00:15:14.190 --> 00:15:17.460 get that far away, the error is just rising 00:15:17.460 --> 00:15:19.100 and rising and rising. 00:15:19.100 --> 00:15:22.040 And then at this critical moment, they switched and they 00:15:22.040 --> 00:15:26.970 sight on the lunar horizon with these three stars. 00:15:26.970 --> 00:15:30.480 And you can see the error just goes down almost to nothing, 00:15:30.480 --> 00:15:33.720 compared to the later calculated accurate value. 00:15:33.720 --> 00:15:37.840 So they plotted this stuff obsessively and 00:15:37.840 --> 00:15:40.140 were extremely clear. 00:15:40.140 --> 00:15:41.450 Actually, this is the actual error. 00:15:41.450 --> 00:15:47.040 That's the position of where their orbit is and depending 00:15:47.040 --> 00:15:48.110 on where you are. 00:15:48.110 --> 00:15:50.890 And that was part of the common filter problem is you 00:15:50.890 --> 00:15:52.700 only want to take the sightings to update the 00:15:52.700 --> 00:15:55.110 solution when it's going to really be better than the 00:15:55.110 --> 00:15:57.320 noise in the process to do it. 00:15:57.320 --> 00:15:59.520 And Batten was very good at figuring out 00:15:59.520 --> 00:16:01.410 when that would be. 00:16:01.410 --> 00:16:02.660 Another view of it. 00:16:05.840 --> 00:16:08.000 Here's the one in the Lunar Module. 00:16:08.000 --> 00:16:10.720 Remember, the crews are standing up. 00:16:10.720 --> 00:16:11.480 You can see them here. 00:16:11.480 --> 00:16:14.620 Here's the astronaut right there. 00:16:14.620 --> 00:16:17.060 Again sort of considering obviously this human and 00:16:17.060 --> 00:16:18.850 machine computing thing that I've been 00:16:18.850 --> 00:16:20.100 talking about all semester. 00:16:24.430 --> 00:16:27.960 Another view of the landing. 00:16:27.960 --> 00:16:30.800 So I wanted to show you one little clip about the software 00:16:30.800 --> 00:16:32.400 for this, because it's actually really interesting. 00:16:36.410 --> 00:16:41.920 The entire work statement for MIT's role in the Apollo 00:16:41.920 --> 00:16:45.770 program is 10 pages long. 00:16:45.770 --> 00:16:48.580 This is before it became $140 million program. 00:16:48.580 --> 00:16:53.640 And one line says, of course MIT will provide the programs 00:16:53.640 --> 00:16:58.730 that are required to run them the computer. 00:16:58.730 --> 00:17:01.220 And it doesn't use the word "software." The word software 00:17:01.220 --> 00:17:02.240 hadn't been invented. 00:17:02.240 --> 00:17:04.440 And I'll show a graph in a little bit. 00:17:04.440 --> 00:17:07.160 By the end of the program, they were worried they may not 00:17:07.160 --> 00:17:08.750 make the landing on the Moon because the 00:17:08.750 --> 00:17:10.230 software wouldn't be ready. 00:17:10.230 --> 00:17:14.170 So the transition I would say between people bragging about 00:17:14.170 --> 00:17:16.430 how big their computers are and Apollo, was the beginning 00:17:16.430 --> 00:17:19.250 of people bragging about how small they are. 00:17:19.250 --> 00:17:21.760 And then also the transition from idea that hardware was 00:17:21.760 --> 00:17:24.020 really unreliable. 00:17:24.020 --> 00:17:26.579 But one of the things this computer used was really the 00:17:26.579 --> 00:17:29.315 first silicon chips, integrated circuits. 00:17:32.030 --> 00:17:38.100 They bought 60% of the entire US production of semiconductor 00:17:38.100 --> 00:17:39.630 chips in 1964. 00:17:39.630 --> 00:17:43.090 It gave a huge boost to this budding, very uncertain 00:17:43.090 --> 00:17:45.280 technology. 00:17:45.280 --> 00:17:50.610 And that made the hardware actually really reliable. 00:17:50.610 --> 00:17:52.420 And like I said, they never really had a 00:17:52.420 --> 00:17:53.730 hardware failure in fight. 00:17:53.730 --> 00:17:56.940 But there were all kinds of funky software bugs that they 00:17:56.940 --> 00:17:59.520 kind of uncover and the beginning of that software 00:17:59.520 --> 00:18:01.260 could kill you too. 00:18:01.260 --> 00:18:02.440 AUDIENCE: What was the percentage again? 00:18:02.440 --> 00:18:04.580 PROFESSOR: 60%. 00:18:04.580 --> 00:18:06.860 So I'll play this little clip, which is from a video that we 00:18:06.860 --> 00:18:07.760 made a couple years ago. 00:18:07.760 --> 00:18:09.080 [VIDEO PLAYBACK] 00:18:09.080 --> 00:18:11.720 PROFESSOR: So one of things interesting about that is that 00:18:11.720 --> 00:18:13.810 they wove this core-rope memory. 00:18:13.810 --> 00:18:16.930 And we started this class talking about the relationship 00:18:16.930 --> 00:18:20.240 of industry in New England, and typically the textile 00:18:20.240 --> 00:18:23.400 industry to the foundation of MIT and how many of the people 00:18:23.400 --> 00:18:26.200 who had founded that industry were MIT's early trustees. 00:18:26.200 --> 00:18:29.540 And here we are a hundred years later, and the textile 00:18:29.540 --> 00:18:32.693 industry which is essentially dying or dead by that time in 00:18:32.693 --> 00:18:38.250 New England, these workers are still very much using those 00:18:38.250 --> 00:18:39.230 same kinds of skills. 00:18:39.230 --> 00:18:43.430 Literally, that software was manufactured in an old textile 00:18:43.430 --> 00:18:45.210 plant in Waltham, Massachusetts, which still 00:18:45.210 --> 00:18:46.800 exists today. 00:18:46.800 --> 00:18:49.660 And also we probably mentioned Digital Equipment Corporation. 00:18:49.660 --> 00:18:51.860 They started in old textile plants. 00:18:51.860 --> 00:18:56.320 If you go today to Manchester, New Hampshire or even Lowell, 00:18:56.320 --> 00:18:59.220 you'll find high-tech software companies and stuff in these 00:18:59.220 --> 00:19:00.270 old textile factories. 00:19:00.270 --> 00:19:02.140 So there is this sort of site all of 00:19:02.140 --> 00:19:04.570 industrial decline and renewal. 00:19:04.570 --> 00:19:05.880 This is one model. 00:19:05.880 --> 00:19:07.390 You can see, those of you familiar with 00:19:07.390 --> 00:19:11.850 microcontrollers, it looks very similar to what you might 00:19:11.850 --> 00:19:15.110 see today, all the different inputs, radars, and sensors, 00:19:15.110 --> 00:19:19.520 and things, and the outputs for the Lunar Module Another 00:19:19.520 --> 00:19:21.360 view of the system. 00:19:21.360 --> 00:19:26.060 Totally fly-by-wife, so every time any commands from a 00:19:26.060 --> 00:19:30.180 joystick, which weren't used very commonly anyway, they 00:19:30.180 --> 00:19:33.140 always went through the digital computer before going 00:19:33.140 --> 00:19:34.390 out to any of the thrusters. 00:19:36.800 --> 00:19:39.790 At first, the astronauts wanted direct wires, physical 00:19:39.790 --> 00:19:42.520 wires, to control the solenoids for the thrusters. 00:19:42.520 --> 00:19:47.550 But there are 16 attitude thrusters on the Lunar Module. 00:19:47.550 --> 00:19:51.800 And you can imagine trying to, in these clusters of four, 00:19:51.800 --> 00:19:53.890 imagine trying to control each one of those individually. 00:19:53.890 --> 00:19:57.170 It was just not possible to do. 00:19:57.170 --> 00:19:59.790 Here's one view that I like to show from the Draper-- 00:19:59.790 --> 00:20:02.930 the instrumentation lab, of no automation in 00:20:02.930 --> 00:20:04.880 the cockpit, no software. 00:20:04.880 --> 00:20:08.460 The crew is completely busy, overwhelmed, doing all these 00:20:08.460 --> 00:20:09.420 different jobs. 00:20:09.420 --> 00:20:11.030 And then full automation. 00:20:11.030 --> 00:20:13.560 They're sleeping and smoking cigars and playing cards. 00:20:13.560 --> 00:20:15.860 And all they have to do is look at the abort button. 00:20:15.860 --> 00:20:17.910 It's pretty much how the launch happened. 00:20:17.910 --> 00:20:19.410 And still happens in the shuttle today. 00:20:19.410 --> 00:20:23.890 There's no manual control for the first part of the launch. 00:20:23.890 --> 00:20:28.770 And the astronauts were convinced they could fly the 00:20:28.770 --> 00:20:32.790 Saturn V rocket by hand, off the launch pad, which turned 00:20:32.790 --> 00:20:34.750 out not to be the case. 00:20:34.750 --> 00:20:37.350 And they tried to find a kind of middle ground between these 00:20:37.350 --> 00:20:38.805 two positions. 00:20:41.400 --> 00:20:43.620 Another view of that navigation flow. 00:20:43.620 --> 00:20:46.240 This one is a little bit later and much more sophisticated 00:20:46.240 --> 00:20:48.590 than the earlier ones. 00:20:48.590 --> 00:20:52.490 I'll skip over a lot of this. 00:20:52.490 --> 00:20:56.030 That's the DSKY, the display keyboard. 00:20:56.030 --> 00:20:58.990 Another view of it. 00:20:58.990 --> 00:21:02.820 This type of digit, anybody seen those before? 00:21:02.820 --> 00:21:04.010 There's sort of a standard-- 00:21:04.010 --> 00:21:06.190 you can still see them today in some places. 00:21:06.190 --> 00:21:08.490 They're called 7-segment displays, because it's seven 00:21:08.490 --> 00:21:11.420 segments of a number. 00:21:11.420 --> 00:21:12.710 They're a little bit obsolete today. 00:21:12.710 --> 00:21:15.270 But they're sort of part of calculators and stuff. 00:21:15.270 --> 00:21:17.960 As near as I can tell, that display was invented for the 00:21:17.960 --> 00:21:19.210 Apollo computer. 00:21:29.100 --> 00:21:32.100 There's one guy on the team who claims that he did it. 00:21:32.100 --> 00:21:34.270 And I've never found anybody who claims that they did it 00:21:34.270 --> 00:21:36.070 before that. 00:21:36.070 --> 00:21:39.320 So this kind of numerical output, which became an icon 00:21:39.320 --> 00:21:45.660 of the digital age for a long time, was created for Apollo. 00:21:45.660 --> 00:21:49.680 Just beginning to see touch-tone telephones. 00:21:49.680 --> 00:21:51.765 Anybody ever see a touchdown telephone? 00:21:51.765 --> 00:21:53.050 Probably before your time, mainly. 00:21:53.050 --> 00:21:54.620 But. 00:21:54.620 --> 00:21:55.690 Instead of dial tones. 00:21:55.690 --> 00:21:59.220 And this was the layout of the touch-tone telephone. 00:21:59.220 --> 00:22:02.650 And although in the end, AT&T flipped it upside down. 00:22:02.650 --> 00:22:04.820 And the astronauts had a lot of resistance to 00:22:04.820 --> 00:22:05.710 typing things in. 00:22:05.710 --> 00:22:09.800 Because again, typing was not something that highly-trained 00:22:09.800 --> 00:22:11.260 test pilots were used to doing. 00:22:11.260 --> 00:22:14.200 They'd consider that office work and mostly women's work. 00:22:14.200 --> 00:22:17.550 And now of course, everybody types all the time. 00:22:17.550 --> 00:22:19.820 But at the time, that sort of work was not 00:22:19.820 --> 00:22:21.270 their idea of fun. 00:22:21.270 --> 00:22:24.860 This guy is the guy you saw in that slide show, Don Eyles. 00:22:24.860 --> 00:22:26.430 Here he is with Don Draper. 00:22:26.430 --> 00:22:28.640 And I like this picture because-- 00:22:28.640 --> 00:22:30.760 and it actually relates us to some of the 00:22:30.760 --> 00:22:33.800 readings for today. 00:22:33.800 --> 00:22:37.590 It captures the sense that this Apollo project was partly 00:22:37.590 --> 00:22:39.660 a product of what was really the '50s, 00:22:39.660 --> 00:22:42.200 kind of Cold War mentality. 00:22:42.200 --> 00:22:45.770 And by the time it came to fruition in the late '60s, was 00:22:45.770 --> 00:22:47.100 a whole different world. 00:22:47.100 --> 00:22:50.640 In fact, if you look at the naming of the Apollo capsules, 00:22:50.640 --> 00:22:53.770 the first ones are called Eagle and Colombia and these 00:22:53.770 --> 00:22:57.010 kind of super high-brow, patriotic names. 00:22:57.010 --> 00:23:00.170 And then by the later Apollo programs, the capsules are 00:23:00.170 --> 00:23:03.760 called Snoopy and Aquarius, and much more kind of 00:23:03.760 --> 00:23:07.240 reflecting '60s hippies culture. 00:23:07.240 --> 00:23:12.900 And this guy Don Eyles, he graduated from BU with a 00:23:12.900 --> 00:23:16.310 degree in mathematics in 1967, so two 00:23:16.310 --> 00:23:17.310 years before the landing. 00:23:17.310 --> 00:23:20.560 The Apollo program was already beginning to wind down on the 00:23:20.560 --> 00:23:21.600 engineering. 00:23:21.600 --> 00:23:24.840 He got a job at Draper Labs and he started working there. 00:23:24.840 --> 00:23:27.310 And within a few months, he was writing the code that 00:23:27.310 --> 00:23:30.570 controlled the landing on the Moon. 00:23:30.570 --> 00:23:33.120 And most of the code was written by him and a few other 00:23:33.120 --> 00:23:35.950 people for the actual landing. 00:23:35.950 --> 00:23:39.360 And he was 24 years old when Apollo 11 landed on the Moon. 00:23:39.360 --> 00:23:40.450 And he was basically a hippie. 00:23:40.450 --> 00:23:41.420 He had long hair. 00:23:41.420 --> 00:23:45.510 And he talks about, during his lunch breaks, he would go out 00:23:45.510 --> 00:23:48.730 in Cambridge to protest the Vietnam War. 00:23:48.730 --> 00:23:51.510 And then come back to this super-secret facility that was 00:23:51.510 --> 00:23:54.540 working on nuclear guidance and other things and work on 00:23:54.540 --> 00:23:55.895 the Apollo program. 00:23:55.895 --> 00:23:57.110 And he's this great example. 00:23:57.110 --> 00:23:58.270 And he's still around. 00:23:58.270 --> 00:23:59.560 And he's friend of mine these days. 00:23:59.560 --> 00:24:01.620 And he comes to speak in my Apollo class. 00:24:01.620 --> 00:24:03.080 And he's actually a visual artist. 00:24:03.080 --> 00:24:06.090 He does photography downtown. 00:24:06.090 --> 00:24:11.470 And of the way that, on the campus you have this mixture 00:24:11.470 --> 00:24:14.500 of different kinds of cultures and different sorts of 00:24:14.500 --> 00:24:18.470 politics, mixing very freely on the campus. 00:24:18.470 --> 00:24:21.330 And he never found any problem with that. 00:24:21.330 --> 00:24:24.960 And he did his job just fine. 00:24:24.960 --> 00:24:28.030 And he worked at Draper Labs for another 25 years until he 00:24:28.030 --> 00:24:32.120 retired about 10 years ago. 00:24:32.120 --> 00:24:33.340 This is an interesting one because it 00:24:33.340 --> 00:24:34.860 also shows you how-- 00:24:34.860 --> 00:24:36.810 this thing right here is a paper tape. 00:24:36.810 --> 00:24:40.260 And they would literally take the code from the computer, 00:24:40.260 --> 00:24:42.950 and very much in the same spirit of the numerically 00:24:42.950 --> 00:24:46.070 controlled machine tools that we talked about, feed the code 00:24:46.070 --> 00:24:48.590 into this paper tape, into this big machine. 00:24:48.590 --> 00:24:51.980 And it would automatically position this frame over the 00:24:51.980 --> 00:24:53.680 hole, where she's putting her needle through. 00:24:53.680 --> 00:24:57.250 So they did manage to automate it somewhat, where all the 00:24:57.250 --> 00:24:59.300 worker had to do was thread the needle, wait for the thing 00:24:59.300 --> 00:24:59.920 to move, and thread it. 00:24:59.920 --> 00:25:03.020 She didn't have to look up a binary chart and 00:25:03.020 --> 00:25:03.910 then find it there. 00:25:03.910 --> 00:25:06.025 So that work was becoming increasingly automated. 00:25:11.710 --> 00:25:13.950 These are some of the people who were involved in the 00:25:13.950 --> 00:25:15.770 thing, some of who you saw in the video. 00:25:15.770 --> 00:25:18.390 This guy Joe Gavin was at MIT grad. 00:25:18.390 --> 00:25:21.730 He just died, I think less than a year ago. 00:25:21.730 --> 00:25:25.100 And he was vice president of Grumman when they made the 00:25:25.100 --> 00:25:29.210 Lunar Lander and then became president of Grumman later. 00:25:29.210 --> 00:25:30.730 And these other guys are mostly 00:25:30.730 --> 00:25:32.400 programmers of various kinds. 00:25:32.400 --> 00:25:35.170 And they mentioned Margaret Hamilton, one of the very few 00:25:35.170 --> 00:25:38.550 women engineers on the program. 00:25:38.550 --> 00:25:43.530 Here's the manpower for hardware, which peaks in '65 00:25:43.530 --> 00:25:44.500 and goes down. 00:25:44.500 --> 00:25:48.690 And then the software manpower just goes right up and almost 00:25:48.690 --> 00:25:50.380 swamps them by the end. 00:25:57.080 --> 00:25:59.315 I'll just say a little bit more about the landing. 00:26:05.290 --> 00:26:07.820 The landing was the most challenging part 00:26:07.820 --> 00:26:09.850 of the entire mission. 00:26:09.850 --> 00:26:13.360 And up until this point right here, at about 50,000 feet, it 00:26:13.360 --> 00:26:15.590 was entirely controlled by this computer. 00:26:15.590 --> 00:26:18.700 So all these programmers down in Cambridge are sitting 00:26:18.700 --> 00:26:20.460 there, watching it on the big screen. 00:26:20.460 --> 00:26:22.980 And there's a room full of people like this size. 00:26:22.980 --> 00:26:25.090 And each one of them has a little piece of that program 00:26:25.090 --> 00:26:26.180 that's written in. 00:26:26.180 --> 00:26:28.680 And they're all sort of contributing in real time. 00:26:28.680 --> 00:26:31.760 While the astronauts are standing there monitoring, 00:26:31.760 --> 00:26:33.700 until about 500 feet. 00:26:33.700 --> 00:26:37.770 And they have this very clever thing where the computer would 00:26:37.770 --> 00:26:41.480 spit out a number, which you could see down here, like 43. 00:26:41.480 --> 00:26:44.210 And then the commander, this would be Neil Armstrong, would 00:26:44.210 --> 00:26:48.000 look through his window at this number, minus 43, and he 00:26:48.000 --> 00:26:51.960 could look out and see where the target point was. 00:26:51.960 --> 00:26:54.630 And the idea was then he could change the target point if he 00:26:54.630 --> 00:26:56.190 didn't like where it was. 00:26:56.190 --> 00:27:00.550 And this is another view of what he might see. 00:27:00.550 --> 00:27:03.820 So there would be that the landing site there, just sort 00:27:03.820 --> 00:27:06.256 of a passive heads-up display. 00:27:06.256 --> 00:27:09.350 And he could actually jog his joystick and just say, I don't 00:27:09.350 --> 00:27:10.200 like that landing site. 00:27:10.200 --> 00:27:11.530 I want to kick it over there. 00:27:11.530 --> 00:27:12.700 It would move by a degree. 00:27:12.700 --> 00:27:14.940 And then the computer would recalculate the entire 00:27:14.940 --> 00:27:16.720 trajectory and bring them that way. 00:27:16.720 --> 00:27:19.830 And he could do that laterally and fore and aft, as many 00:27:19.830 --> 00:27:22.330 times as he wanted in the course of the landing. 00:27:22.330 --> 00:27:24.280 And in some of the landings, they actually did it up to 18 00:27:24.280 --> 00:27:25.430 or 20 times. 00:27:25.430 --> 00:27:27.290 And the idea was it would gradually converge on a 00:27:27.290 --> 00:27:28.980 perfect spot. 00:27:28.980 --> 00:27:31.920 And the interesting thing about that, which is sort of 00:27:31.920 --> 00:27:35.650 the topic of another story, is that on all six landings, they 00:27:35.650 --> 00:27:39.080 turned that system off at about 500 feet and they flew 00:27:39.080 --> 00:27:42.120 it in a more semi-automatic mode, still 00:27:42.120 --> 00:27:44.580 very much fly by wire. 00:27:44.580 --> 00:27:47.920 But then the story of the Apollo landings became, the 00:27:47.920 --> 00:27:51.300 astronaut intervenes, turns off this sort of balky 00:27:51.300 --> 00:27:54.360 technology, which is landing him in a crater, and saves the 00:27:54.360 --> 00:27:57.260 day by finding the perfect spot and bringing it down. 00:27:57.260 --> 00:28:00.220 And it was not really an accurate story because the 00:28:00.220 --> 00:28:03.380 whole system was designed to interact with the operator to 00:28:03.380 --> 00:28:05.680 allow them to select the right kind of spot. 00:28:05.680 --> 00:28:07.680 But they all turned it off anyway. 00:28:07.680 --> 00:28:10.630 They just wanted to fly. 00:28:10.630 --> 00:28:15.060 Actually Dave Scott, who is an MIT graduate-- 00:28:15.060 --> 00:28:16.910 it's about a third of the people who walked on the Moon 00:28:16.910 --> 00:28:19.190 had degrees from MIT. 00:28:19.190 --> 00:28:25.250 And I teach a graduate course in AeroAstro with Larry Young 00:28:25.250 --> 00:28:27.540 on this whole story. 00:28:27.540 --> 00:28:31.560 And we often have the Apollo astronauts in to 00:28:31.560 --> 00:28:32.390 speak to the students. 00:28:32.390 --> 00:28:34.850 And they'll tell you, they were either Larry's office 00:28:34.850 --> 00:28:37.410 mates or a few of them were his master's students when 00:28:37.410 --> 00:28:39.230 they were here in the early '60s. 00:28:39.230 --> 00:28:41.280 And actually tomorrow, Dave Scott is going to come. 00:28:41.280 --> 00:28:44.160 He was the commander of Apollo 15. 00:28:44.160 --> 00:28:46.420 And he's the only one who I think gave a really accurate 00:28:46.420 --> 00:28:48.290 description of what happened in these last seconds. 00:28:48.290 --> 00:28:52.790 He said, you can say that you wanted to be in the loop if 00:28:52.790 --> 00:28:53.670 anything went wrong. 00:28:53.670 --> 00:28:55.490 But you knew that if something went wrong with a computer, 00:28:55.490 --> 00:28:57.680 you were dead anyway. 00:28:57.680 --> 00:28:59.210 But I came away that whole way and darn it, I 00:28:59.210 --> 00:29:00.480 just wanted to fly. 00:29:00.480 --> 00:29:04.600 And so they all ended up flying it the 00:29:04.600 --> 00:29:06.310 last 500 feet or so. 00:29:06.310 --> 00:29:10.260 And then NASA and the public and the press could all say 00:29:10.260 --> 00:29:18.610 that sort of traditional American values were confirmed 00:29:18.610 --> 00:29:21.190 by these sort of cowboy astronauts landing on the Moon 00:29:21.190 --> 00:29:21.870 by themselves. 00:29:21.870 --> 00:29:25.280 But actually there was this MIT-designed computer there. 00:29:25.280 --> 00:29:27.960 And it's an interesting story too about MIT educations, 00:29:27.960 --> 00:29:31.700 because the earlier crews-- 00:29:31.700 --> 00:29:35.480 Aldren had a Ph.D. from MIT. 00:29:35.480 --> 00:29:38.680 And the earlier astronauts were not 00:29:38.680 --> 00:29:40.310 very academic engineers. 00:29:40.310 --> 00:29:43.880 But gradually over time, they became 00:29:43.880 --> 00:29:45.440 much more highly educated. 00:29:45.440 --> 00:29:48.700 And MIT, with the exception of West Point and the Naval 00:29:48.700 --> 00:29:51.930 Academy and Air Force Academy, the service academies, MIT has 00:29:51.930 --> 00:29:54.660 trained more astronauts than any other school. 00:29:54.660 --> 00:29:59.150 And it became increasingly sort of de rigeur to have a 00:29:59.150 --> 00:30:01.380 master's or a Ph.D in engineering. 00:30:01.380 --> 00:30:05.290 And those crews were much more accepting of these advanced 00:30:05.290 --> 00:30:07.810 techniques for the guidance and much less interested in 00:30:07.810 --> 00:30:10.270 just flying it on in by themselves. 00:30:10.270 --> 00:30:12.400 Alan Shepard, and we mentioned his flight, he 00:30:12.400 --> 00:30:13.650 commanded Apollo 14. 00:30:17.360 --> 00:30:19.750 And he said, aah, if the computer failed, I could have 00:30:19.750 --> 00:30:22.990 just taken over and landed by myself on the Moon. 00:30:22.990 --> 00:30:25.750 Which is physically impossible, because you're 00:30:25.750 --> 00:30:30.090 looking at a terrain landscape that has zero indicators of 00:30:30.090 --> 00:30:31.690 how far away from it you are. 00:30:31.690 --> 00:30:33.950 You could actually be six inches or six miles and you 00:30:33.950 --> 00:30:35.330 wouldn't be able to tell the difference because there's no 00:30:35.330 --> 00:30:40.480 trees, there's no trucks, there are no highways, 00:30:40.480 --> 00:30:42.640 anything to give you a sense of scale. 00:30:42.640 --> 00:30:47.295 And he had a problem with his landing radar. 00:30:47.295 --> 00:30:49.300 It didn't come in until the last few minutes. 00:30:49.300 --> 00:30:52.330 But if the landing radar had never come in, he said he 00:30:52.330 --> 00:30:53.380 would have landed it anyway. 00:30:53.380 --> 00:30:55.175 And he probably would have crashed, if he 00:30:55.175 --> 00:30:56.990 had tried to do that. 00:30:56.990 --> 00:30:58.710 They're actually using this-- 00:30:58.710 --> 00:31:01.010 anybody want to guess what this is, what 00:31:01.010 --> 00:31:02.260 this diagram portrays? 00:31:05.170 --> 00:31:08.140 It's actually a model of the lunar terrain. 00:31:08.140 --> 00:31:10.506 So if you've ever programmed a control system-- we used to 00:31:10.506 --> 00:31:13.680 have this problem building underwater robots all time-- 00:31:13.680 --> 00:31:17.040 and you want to hold a fixed altitude. 00:31:17.040 --> 00:31:19.170 If you're cruising along the bottom of the ocean in a robot 00:31:19.170 --> 00:31:21.320 that's programmed to hold a fixed altitude, so it's 00:31:21.320 --> 00:31:24.270 sending a sonar beam off the bottom and trying to hold an 00:31:24.270 --> 00:31:27.940 altitude, and then you go over a hole, the vehicle is going 00:31:27.940 --> 00:31:29.440 to dive down like this and smash into 00:31:29.440 --> 00:31:31.720 the side of the hole. 00:31:31.720 --> 00:31:33.360 And same thing here. 00:31:33.360 --> 00:31:36.640 If you're trying to fly over a mountain range-- 00:31:36.640 --> 00:31:39.940 it's not a coincidence that the site for the Apollo 11 00:31:39.940 --> 00:31:41.760 landing was called the Sea of Tranquility. 00:31:41.760 --> 00:31:45.070 They found the flattest, most even terrain they could find. 00:31:45.070 --> 00:31:47.270 But the geologists who were running the science 00:31:47.270 --> 00:31:50.220 experiments, really wanted to go into places where there was 00:31:50.220 --> 00:31:52.190 a lot of geological activity, so the terrain 00:31:52.190 --> 00:31:54.690 was a lot more crazy. 00:31:54.690 --> 00:31:58.360 And on the later flights, they really did land very much high 00:31:58.360 --> 00:31:59.560 up in the mountains. 00:31:59.560 --> 00:32:03.450 And this is just a way, where with five line segments, in a 00:32:03.450 --> 00:32:07.310 very, very simple computer model, all it takes is these 00:32:07.310 --> 00:32:11.770 five line segments and like six numbers, you could model 00:32:11.770 --> 00:32:12.960 that there were mountains here. 00:32:12.960 --> 00:32:15.440 And then you expected the terrain to go like that. 00:32:15.440 --> 00:32:18.060 And the computer model could eat all that stuff for lunch 00:32:18.060 --> 00:32:20.300 and it would keep a very stable trajectory and allow 00:32:20.300 --> 00:32:23.030 you to go over the mountains, and then land right at the 00:32:23.030 --> 00:32:26.820 edge, which is what they did on Apollo 15, and 16, and 17, 00:32:26.820 --> 00:32:28.130 a very clever thing. 00:32:31.520 --> 00:32:34.930 That's the view out the window, of Aldrin's side. 00:32:34.930 --> 00:32:38.750 AUDIENCE: When do you begin to see the sort of the decline in 00:32:38.750 --> 00:32:44.570 the pilot-orientedness of the astronauts 00:32:44.570 --> 00:32:47.230 wanting to control more? 00:32:47.230 --> 00:32:51.070 Because the thing that your lecture brings to my mind is 00:32:51.070 --> 00:32:54.320 the book, The Right Stuff, in which that's a big issue. 00:32:54.320 --> 00:32:58.880 But clearly what you're saying is over time, that declines. 00:32:58.880 --> 00:33:01.900 PROFESSOR: Hopefully, we're seeing it now. 00:33:01.900 --> 00:33:03.280 After the Moon landing, what did they do? 00:33:03.280 --> 00:33:06.240 They started sending an airplane into orbit. 00:33:06.240 --> 00:33:08.020 It wasn't the wisest choice. 00:33:08.020 --> 00:33:10.540 But it was because the astronauts wanted to fly 00:33:10.540 --> 00:33:12.860 something that had wings on it. 00:33:12.860 --> 00:33:15.310 And it's not a very efficient way to go to and from space. 00:33:19.150 --> 00:33:21.890 AUDIENCE: So was Alex Roland right all along? 00:33:21.890 --> 00:33:24.140 PROFESSOR: Yeah, in some way. 00:33:24.140 --> 00:33:28.060 But from MIT's point of view, again building into the Bill 00:33:28.060 --> 00:33:34.720 Leslie piece from today, the Apollo program ends in 1972. 00:33:34.720 --> 00:33:37.230 It has this huge triumph in 1969. 00:33:37.230 --> 00:33:40.000 And that's right when all these protests end up 00:33:40.000 --> 00:33:43.050 happening and the Draper Labs gets spun out. 00:33:43.050 --> 00:33:45.840 They were extremely offended and insulted by that move. 00:33:45.840 --> 00:33:49.310 And there is still hard feelings about it today. 00:33:49.310 --> 00:33:52.950 A lot of the people who worked at the Instrumentation Lab 00:33:52.950 --> 00:33:55.050 were happy to work on a civilian project. 00:33:55.050 --> 00:33:57.660 And one of the reasons they liked working on Apollo was 00:33:57.660 --> 00:34:00.410 that it was a non-weapons kind of project. 00:34:00.410 --> 00:34:03.240 And then they felt like they got the bad end of the rap 00:34:03.240 --> 00:34:04.690 during a lot of the protests anyway. 00:34:04.690 --> 00:34:06.710 There was still a lot of military funding and a lot of 00:34:06.710 --> 00:34:10.139 weapons work going on there. 00:34:10.139 --> 00:34:14.590 But it's sort of this irony of this moment when this part of 00:34:14.590 --> 00:34:20.159 MIT has this world shattering technological triumph in a 00:34:20.159 --> 00:34:23.580 way, and then also becomes the brunt of it. 00:34:23.580 --> 00:34:26.210 And it just shows you again the ways that all these things 00:34:26.210 --> 00:34:27.870 on this campus and in the country were 00:34:27.870 --> 00:34:29.159 conflicted at the time. 00:34:29.159 --> 00:34:33.530 And somebody wrote recently that at the time it seemed 00:34:33.530 --> 00:34:36.060 like the hippies and the Moon landings were the furthest 00:34:36.060 --> 00:34:36.650 thing apart. 00:34:36.650 --> 00:34:39.690 One of them was the military industrial complex and one of 00:34:39.690 --> 00:34:42.400 them was this kind of Utopian vision of the world. 00:34:42.400 --> 00:34:45.030 But looking back 30 years later, you can see they have a 00:34:45.030 --> 00:34:45.690 lot in common. 00:34:45.690 --> 00:34:48.469 They were both sort of Utopian, futuristic visions 00:34:48.469 --> 00:34:52.239 that never quite succeeded in the promise that they held. 00:34:52.239 --> 00:34:55.210 And yet they both influenced the world in different ways 00:34:55.210 --> 00:34:57.139 that people hadn't really expected. 00:34:57.139 --> 00:34:58.460 And that was true on campus. 00:34:58.460 --> 00:35:01.170 So mentioned in their response paper, I'm forgetting who, 00:35:01.170 --> 00:35:08.310 about how it was really the one moment there was major 00:35:08.310 --> 00:35:09.930 political activism on campus. 00:35:09.930 --> 00:35:11.060 There were other places too. 00:35:11.060 --> 00:35:15.100 But in this entire story, we were teaching you the history 00:35:15.100 --> 00:35:19.670 of Yale University or NYU or Columbia. 00:35:19.670 --> 00:35:22.280 It's a very political story the way the students are 00:35:22.280 --> 00:35:25.600 responding to the currents in the outside world and how 00:35:25.600 --> 00:35:26.900 those things played out on campus. 00:35:26.900 --> 00:35:30.870 And it's a much more muted story here for reasons that 00:35:30.870 --> 00:35:31.890 might be worth discussing. 00:35:31.890 --> 00:35:35.740 And in the discussion, it's really remarkable and notable 00:35:35.740 --> 00:35:39.700 this one moment in the '70s, when it happened. 00:35:39.700 --> 00:35:45.455 And whereas, I went to college at Yale in the '80s and there 00:35:45.455 --> 00:35:49.080 were students being arrested all the time for protests and 00:35:49.080 --> 00:35:51.470 occupying the president's office and things. 00:35:51.470 --> 00:35:55.680 It became almost a kind of a cartoon of itself, 00:35:55.680 --> 00:35:58.040 it happened so often. 00:35:58.040 --> 00:36:04.400 Well, if you noticed in the 150th Exhibit, one of the 150 00:36:04.400 --> 00:36:07.960 objects is a tape of the Grateful Dead playing on the 00:36:07.960 --> 00:36:09.710 front steps of the student center. 00:36:09.710 --> 00:36:13.390 And I think it was April 1970, was that when Kent State was? 00:36:13.390 --> 00:36:17.010 And the thing they write about it, it was within a week after 00:36:17.010 --> 00:36:18.940 Kent State. 00:36:18.940 --> 00:36:21.130 And the campus was extremely tense. 00:36:21.130 --> 00:36:23.540 Everybody was very unsure what was going to happen. 00:36:23.540 --> 00:36:26.360 And when they played their music, they were very aware of 00:36:26.360 --> 00:36:29.240 that and really tried to make it be a sort of soothing, 00:36:29.240 --> 00:36:34.980 calming moment as opposed to a fractious, contentious, 00:36:34.980 --> 00:36:36.360 potentially violent moment. 00:36:36.360 --> 00:36:39.080 And that's one of the reasons Debbie chose it as part of the 00:36:39.080 --> 00:36:40.330 150 objects. 00:36:42.640 --> 00:36:44.930 AUDIENCE: Very interesting. 00:36:44.930 --> 00:36:48.040 PROFESSOR: So that takes us up to 1970 or so. 00:36:48.040 --> 00:36:51.220 And then there's four more decades to deal with, between 00:36:51.220 --> 00:36:53.360 now and then, some of which we read about. 00:36:53.360 --> 00:36:58.670 The Cambridge recombinant DNA story is in some ways very 00:36:58.670 --> 00:37:01.200 much a continuation of this sort of story. 00:37:01.200 --> 00:37:04.113 Cambridge was, I'm not sure how much it still is, it still 00:37:04.113 --> 00:37:07.280 is a little bit, a very left-leaning community outside 00:37:07.280 --> 00:37:11.520 of the university, very activist, very concerned about 00:37:11.520 --> 00:37:14.900 these big, potentially scary technologies. 00:37:14.900 --> 00:37:19.730 That was very much the mood of the time, was what is this big 00:37:19.730 --> 00:37:22.670 nasty force of technology doing to our world? 00:37:22.670 --> 00:37:24.900 And MIT, it was pretty easy for to become 00:37:24.900 --> 00:37:26.460 the center of that. 00:37:26.460 --> 00:37:30.040 And John Durant's piece shows you how that played out, 00:37:30.040 --> 00:37:35.950 arguably in a constructive way, a very interesting one. 00:37:35.950 --> 00:37:38.140 And then in '80s, the military-- 00:37:38.140 --> 00:37:40.940 we talked about this a little bit last time-- 00:37:40.940 --> 00:37:43.100 got very much going again under Reagan. 00:37:43.100 --> 00:37:47.060 And a lot of money came into computer science and other 00:37:47.060 --> 00:37:49.250 engineering disciplines. 00:37:49.250 --> 00:37:53.840 But also the economics of technology and the challenge 00:37:53.840 --> 00:37:55.470 from Japan became a big issue. 00:37:55.470 --> 00:37:57.490 That had a lot of influence on campus. 00:37:57.490 --> 00:38:01.480 All the while, biotech and biology is sort of creeping up 00:38:01.480 --> 00:38:06.138 in importance and dollar value. 00:38:06.138 --> 00:38:09.040 And then the Cold War ends. 00:38:09.040 --> 00:38:13.840 Chuck Vest becomes president in the late either '89 or '90, 00:38:13.840 --> 00:38:15.590 '91 I think. 00:38:15.590 --> 00:38:17.660 He became president right about when I came here as a 00:38:17.660 --> 00:38:18.930 grad student. 00:38:18.930 --> 00:38:21.550 And the big question on everybody's mind was what at 00:38:21.550 --> 00:38:22.800 that point? 00:38:26.990 --> 00:38:29.690 MIT is dependent on government funding for so long. 00:38:29.690 --> 00:38:32.720 Now that the Cold War is over, are we going to just shrivel 00:38:32.720 --> 00:38:34.140 up and die? 00:38:34.140 --> 00:38:36.600 And the pendulum goes again. 00:38:36.600 --> 00:38:39.010 Where do they go? 00:38:39.010 --> 00:38:40.210 Back towards industry. 00:38:40.210 --> 00:38:41.980 And the '90s is very much-- 00:38:41.980 --> 00:38:44.100 I mean the government research support is always there, but 00:38:44.100 --> 00:38:46.040 very much industry. 00:38:50.030 --> 00:38:52.240 I remember Chuck Vest saying-- it was probably pretty late in 00:38:52.240 --> 00:38:54.950 his presidency, soon before he stepped down, in a faculty 00:38:54.950 --> 00:38:58.030 meeting, I've spent so many years cultivating industrial 00:38:58.030 --> 00:38:59.830 sponsors, it's very difficult. 00:38:59.830 --> 00:39:01.320 It's very time consuming. 00:39:01.320 --> 00:39:03.570 I would be very happy for the government to start up again 00:39:03.570 --> 00:39:04.350 and support-- 00:39:04.350 --> 00:39:07.770 I mean it didn't go down ever, as much as 00:39:07.770 --> 00:39:09.460 people feared it did. 00:39:09.460 --> 00:39:14.890 But it became less of a percentage of MIT's income. 00:39:14.890 --> 00:39:18.480 Then the financial crisis in '08 happens and the stimulus 00:39:18.480 --> 00:39:20.890 package comes in, more government. 00:39:20.890 --> 00:39:23.980 And the government runs out of money, less government. 00:39:23.980 --> 00:39:25.770 So this pendulum keeps swinging. 00:39:28.540 --> 00:39:30.440 AUDIENCE: The periods are shorter. 00:39:30.440 --> 00:39:31.710 PROFESSOR: The periods are maybe shorter. 00:39:31.710 --> 00:39:32.960 It could be true.