I had told the organizers I could give a talk.But a week or so before the event,克里斯托弗告诉我，他认为我计划说的话没有它可能的有趣。徳赢彩票游戏事实上，他可以做一些更有趣和更相关的演示。
克里斯托弗是个狂热的人数学软件user for years now.And he likes hooking数学软件最近最受欢迎的两种设备是Arduino板和四翼无人机。
上周日，我和他一起走上舞台，站在只有300多人的一个看台前，carrying a quadricopter.(I wasn't trusted with the Arduino board.)
Christopher had told me that I shouldn't talk too long—and that then I should hand over to him.He'd been working on his demo the night before,那天早上早些时候。我建议他应该练习他要说的话，but he'd have none of that.Instead,up to the last minute,he spent his time cleaning up code for the demo.
我这辈子一定讲过几千次了，但整个情况让我很紧张。Arduino董事会能工作吗？四翼飞机会飞吗？What would Christopher do if it didn't?
I don't think my talk was particularly good.But then Christopher bounced onto the stage,and soon was typing raw数学软件code in front of everyone—with me now safely off on the side (where I snapped this picture):
His demo was pretty neat.他在Arduino板上安装了一个电位计。他把它设置成只需要输入一个命令数学软件to get its value:
Then it was动态[Arduinoanalogread，和数学软件is dynamically displaying the value in real time as he adjusted the potentiometer.
Then he makes it into a gauge (er,这实际上是未来版本的数学软件，但Christopher热衷于内部开发构建）：
And then he says he's going to make a dynamic plot of it.And pretty soon he's typing the数学软件程序，自信地按SHIFT RETURN，它实际工作：
Then he's on to using an ultrasound sensor,让它根据距离产生音符。
然后他就上了四翼飞机。He'd been going back and forth with someone at our company for a few days before,试图摆脱与四头肌's API.I had seen the quadricopter fly that morning,but I k徳赢中国new Christopher had changed the code quite a bit since then.
His plan was to have a single line of数学软件code that would make the quadricopter fly a specified 3D path.He had a list of points for a square,输入代码行，and pressed Shift-Return,and… nothing happened!
我猜克里斯托弗13年来调试了很多代码。现在他开始在观众面前做。徳赢彩票游戏A missing function definition.A missing command to connect to the device.他发现了不少东西。And I was getting ready to call out that he should just give up.
But then… the sound of quadricopter blades,and up the quadricopter goes… flying its loop on the stage,and landing.
它真的起作用了！It was pretty neat,只需输入一行代码数学软件，然后让一些物理物体以我们指定的模式飞行：
在另一次飞行之后，观众有问题。一个人问四翼飞机是否能对环境做出反应。这使克里斯托弗开始了更多的“旁观者节目”。And actually,it took him only a line of code to get the real-time video from the flying quadricopter,and feed it through simple数学软件image processing:
这一切都奏效了，给我留下了很深的印象（hereis the full video).而且，yes,Christopher was clearly right that his topics were very relevant to Maker Faire.In fact,it seemed like Arduino and quadricopters were two of the three main technical themes of the show.The third was 3D printing.
And I was reminded that one of my own early applications of 3D printing years before had been connected to another of my children.In 2006,my daughter Catherine (then 9 years old) was very into 3D geometry,喜欢探索3D polyhedra我们引进的数学软件6。
Catherine had 2D printouts of many different cases,and one day we decided to try making them 3D.It took a little wrangling,但没过多久，凯瑟琳和我就去了一家充满塑料粉尘的“3D打印店”。from which a little zoo of polyhedral koalas emerged:
Every year there's more and more for me to learn from my children.我最大的孩子，now age 16,我已经成为一个相当成功、极其老练的企业家，我正努力从他身上汲取我所能吸收的商业智慧。其他三个还没有“启动”，but each has their definite interests.
For Christopher it's technology and product design.Learning 徳赢彩票游戏about every 徳赢中国new and emerging technology he can,and developing his own ideas—and often strong opinions—徳赢彩票游戏about it.(At Maker Faire,我感兴趣地注意到他对覆盆子皮… and his long discussion 徳赢彩票游戏about what it would mean to have数学软件running on it…)
Christopher has always been an energetic explainer of things.但上周末第一次见他向大批观众“解释”却很有趣。他绝对是我们联合演讲的明星。And—despite a few tense moments—it was pretty fun for me to see two progeny of very different kinds—Christopher and数学软件—一起工作so nicely.