As I said sensing and actuation is all about interfacing the real world to the single board computer and the digital world. What makes up a sensor? The transducer is the most important part. It converts energy from one domain into all of them. In our case. Real world signals into electrical world signals and vice versa. Then there are some signal conditioning aspects involved before we can actually convert them into discreet signals. There's two main things that I want you to remember about the signal conditioning. The first one is an amplifier. To bring the low level signals from the transducer to the full range of the a to d converter. And number two, a low pass filter to remove all the frequency components above certain frequency. We'll come back to this a little bit later. The ADC is a mixed signal component, that has both analog circuitry and digital circuitry. We then use the processor, the ARM processor or the DSP, to process these discrete signals. And finally there is a modem. It can be bluetooth, wi-fi, ZigBee, or even cellular van to connect to the internet either directly, or through some other gateway that connects to the internet. So that is the sensing pipeline. Let's look at the activation pipeline. It's pretty much similar to the functionalities in the sensing pipeline. The major difference is [COUGH] the power amplifier to drive the transducer, instead of a low-noise amplifier. The transducers can be LEDs, your screen, etcetera. So what you can do with this pipeline is, you can open garage doors, build an industrial control system, so on and so forth. But do not underestimate the value of the cloud in this pipeline to which we can connect using the modem. This is what gives the IOT platform all it's power. So from the very first course you may recall that the invention of the telephone started with the microphone and the receiver. And if you remember Alexander Graham Bell, Elisha Gray, Antonio Mucci,were all involved in developing the transducers to convert speech signals into electrical signals, and back into speech signals. The microphone and the speaker are receiver as it's called in the hearing aid community. We also saw the remaining blocks, the ADC, DSP, the modem. All came together in the evolution of the telephone to the digital telephony and the cellular phones. So now we get to leverage all of this in the IOT platform. This is the connection with the telephony in the IOT platform. So, there are many real world signals we can now play this in addition to speech. I list some of them here. Electrocardiography is for heart signals. It measures the electrical activity in the heart muscles. EEG is the electroencephalography. These are the bio potentials that can be recorded of the scalp. Very useful for brain computer interface, diagnosis and treatment of concussions, NTBI especially, sports related injuries, ice hockey, NFL, et cetera. And also cognitive impairments do to aging. HRV stands for heart rate variability, and that is finding what's the fabrications in both fitness and healthcare. Did the possibilities of signals that we can sense and do something clever, is limitless and we look forward to you using the signals in some clever way in your capstone project. So, the next question is, what sort of processing can we do on these signals? We already saw on the telephony world that you can do compression and reconstruction of speech signals in the digital telephony and correspond. We will go a little bit deeper in this in course four. There where will be cover of WIP. Why solar IP, the internet protocol. Other examples include storage and which evolved, specifically like iPod or Netflix or YouTube or eReader's, these are there. You have all of the double of the content, and stored in the cloud, and you can use the activation to tell you what the content. Machine learning, big data systems, as your sensing all kinds of different mortalities in the real world, you can understand the trends in the real world, and possibly act upon them. Healthcare is the topic where I spend most of my time these days. And hopefully we may offer some more courses depending on the interest. So when someone says they have a novel sensor for you that you can use in you IUP project, or your product, they usually mean the three blocks that we have here. The transducer, signal conditioning and A to D converter. But not always, it maybe just the transducer, or it may even include some near fill communication radio like bluetooth that sends signals wirelessly. So, now that we have looked at all the different parts of the sensing and actuation pipeline, you will be able to tell what is involved from the context when you're looking at the sensors and the actuators that you can use in your project.
