硬件常用术语

由于硬件经常就是缩写命名，所以直接上英文

General terminology
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voltage dividers - also known as potential dividers, they divide voltage across the components of a circuit. Voltage (out) is less than voltage (in).




voltage regulators - a regulator designed to automatically maintain voltage in a circuit




current dividers - same concept as a voltage divider, they split current between the branches of the divider. The current (out) is less than the current (in)




current regulators - A device for controlling the current output of a generator (which increases with engine speed) by opening a switch when the current exceeds a certain value, thus protecting the generator from damage due to excess current. (cut and paste this definition, but I thought it was a really good explanation)




battery monitors - monitor's a batteries voltage, current, temperature etc (not sure about this one, please clarify)




breakout boards - Breakout boards are usually used to connect Integrated circuits to breadboards by breaking out the connections of things that would not be easily connected using a standard breadboard. It also used as an interface between PC's and other devices.




I2C - Inter-Integrated Circuit, "two wire interface"




PWM - (Detailed info: http://www.arduino.cc/en/Tutorial/PWM) A technique for getting analog results with digital means. Digital control is used to create a square wave, a signal switched between on and off. The duration of "on time" is called the pulse width. To get varying analog values, you change, or modulate, that pulse width.




SPI - (Serial Peripheral Interface Bus) A synchronous serial data link standard that operates in full duplex mode. Devices communicate in master/slave mode where the master device initiates the data frame. The SPI bus can operate with a single master device and with one or more slave devices.




UART - (Detailed info: http://www.usr.com/support/s-cour/s-cour-docs/10589.htm) UART is (Universal Asynchronous Receiver/Transmitter) is a chip with programming that controls the interface of a computer with it's attached serial devices. it pretty much controls the serial port of the pc.




Voltage Regulation - taking some raw voltage (from a battery, or any other unreliable source) and turning it into a steady voltage source at some other voltage. For example, our batteries may go from ~30V at full charge to ~20V at empty. We want a "voltage regulator" to turn this unsteady battery voltage into a steady 5V. Voltage Regulators can either be of the Boost, Buck, or Boost-Buck variety.




Boost Regulator - A voltage regulator that takes a lower voltage, and turns it into a higher one.




Buck Regulator - A voltage regulator that takes a higher voltage, and turns it into a lower one.




Boost-Buck Regulator - A voltage regulator that can take any voltage in a range (either higher or lower than the desired voltage) and turn it into the desired voltage.




DC-DC Conversion - Voltage regulation which converts some DC voltage level to some other DC voltage level. There are two main ways to do this: "Linear Regulators" and "Switching Regulators", both with their own pros and cons.




Linear Regulator - A cheap and clean, yet inefficient DC regulator. You can think of Linear Regulators as active voltage-dividers. That is, there is some sensor inside the device which can measure the amount of voltage on the output, and can change the R2 resistance of the divider such that the output voltage stays within the desired range. So, when the output voltage is too high, the little controller will lower the R2 resistance and 
dump the extra juice into ground. This is important, because it makes a Linear Regulator pretty inefficient - especially when the difference between the raw input voltage and the desired regulated voltage is large. Any difference between the raw voltage and the desired voltage is gotten rid of by just wiring it into ground. However, Linear Regulators are often cheap-as-dirt, and produce relatively clean outputs.




Switching Regulator - A more expensive and noisy, but very efficient DC regulator




Switched-Mode Regulator) Switching Regulators work just like our motor drivers: they reduce the apparent output voltage by just switching themselves on and off. The input current either flows through the device, or it doesn't - the extra juice doesn't have to be sent to ground! By changing the proportion of time the device is on versus off (known as the 
duty-cycle), a little controller inside the device can easily regulate the output voltage so that it is in the desired range. The problem is that the voltage from the output of a naive implementation would just be a square wave - not a clean regulated signal. To combat this, Switched Regulator designers will often put a few capacitors into their devices to smooth out the highs and lows of this square wave so that the output looks more like a constant voltage. Additionally, a device's datasheet will often specify some specific capacitor values that you need to add onto your PCB to smooth this out further. Unfortunately, it can be hard to completely eliminate these highs and lows (called ripple), and so Switching Regulators are best used for digital electronics which are more impervious to small power supply fluctuations. Also, all of this switching creates some magnetic noise as well, so you need to be sure to be wary of this when placing sensitive electronics (e.g. compasses/IMUs).




IMU-(Inertia Measurement Unit) an electronic device that measures and reports on a craft's velocity, orientation, and gravitational forces, using a combination of accelerometers and gyroscopes. IMUs are typically used to maneuver aircrafts.




Vectornav- a supplier of miniature inertial measurement units (IMUs), attitude Heading Reference Systems (AHRS), and inertial sensors.




AVR-microcontrollers that use on-chip flash memory for program storage. AVRs have 32 single-byte registers and are classified as 8-bit RISC devices




Arduino- a popular open-source single-board microcontroller, consisting of a simple open hardware design for the Arduino board with an Atmel AVR processor and on-board input/output support. The software consists of a standard programming language compiler and the boot loader that runs on the board.




Arduino Shield- boards that can be plugged on top of the Arduino PCB (Printed Circuit Boards) extending its capabilities. The different shields follow the same philosophy as the original toolkit: they are easy to mount, and cheap to produce.




ARM- a 32-bit reduced instruction set computer (RISC) instruction set architecture. The relative simplicity of ARM processors makes them suitable for low power applications. Moreover, they are relatively low-cost and have both small microprocessors and microcontrollers.




Leaflabs Maple- a 32-bit Arduino Compatible Microcontroller that runs on a maximum of 72 MHz and compatible with shields designed for the Arduino. It could also be powered via USB, a wall adapter, or it can run off of a rechargeable lipo battery.




Attitude: Roll, Pitch, Yaw- the angles of rotation in three dimensions about the vehicle's center of mass, which are also the three critical flight dynamics parameters. The equilibrium roll angle is known as wings level or zero bank angle. A pitching moment is a vertical force applied at a distance forward or aft from the center of gravity of the aircraft, causing the aircraft to pitch up or down. Yaw is known as "heading". The equilibrium pitch angle in aircraft refers to angle of attack.




Kalman Filter- The algorithm works recursively in real time on streams of noisy input observation data and filters out errors using a least-squares curve-fit optimized with a mathematical prediction of the future state generated through a modeling of the system's physical characteristics. The model estimate is compared to the observation and this difference is scaled by a factor known as the Kalman Gain, which is then feedback as an input into the model for the purpose of improving subsequent predictions.




PID-(Proportional–Integral–Derivative Controller) a generic control loop feedback mechanism (controller) that calculates an "error" value as the difference between a measured process variable and a desired setpoint. The controller attempts to minimize the error by adjusting the process control inputs.




DIP-(dual in-line package) an electronic device package with a rectangular housing and two parallel rows of electrical connecting pins.




SMD-(Surface Mount Device) a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards.




Lidar-(Light Detection And Ranging) an optical remote sensing technology that can measure the distance to, or other properties of a target by illuminating the target with light, often using pulses from a laser.




Sonar- a technique that uses sound propagation to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Passive sonar is essentially listening for the sound made by vessels while active sonar is emitting pulses of sounds and listening for echoes.




Laser Rangefinder- a device which uses a laser beam to determine the distance to an object. The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender.




Speed Controller- an electronic circuit with the purpose to vary an electric motor's speed, its direction and possibly also to act as a dynamic brake.




Servo- an automatic device that uses error-sensing negative feedback to correct the performance of a mechanism.




Brushless Motor- electric motors powered by direct-current (DC) or alternating current (AC) electricity and having electronic commutation systems, rather than mechanical commutators and brushes.




ADC- (Air Data Computer) an essential avionics component which can determine the calibrated airspeed, Mach number, altitude, and altitude trend from input data from sensors such as an aircraft's pitot-static system, gyroscopes, GPS and accelerometers.




DAC- (digital-to-analog converter) a device that converts a digital (usually binary) code to an analog signal.