Wednesday 23 October 2013

Monday 14 October 2013

CONTROLLING DEVICES

SECTION 5: CONTROLLING DEVICES
24.   What is processing (P.259)
Processing is the changing of data from one form to another being generally input data to output information in which humans are able to use.

25.   Provide an overview of the CPU's function. Include an overview of the microprocessor and the co-processor (p. 259).
The CPU is a part of the computer in which processes and controls functions within the computer. CPU’s can be either a microprocessor or co-processor. A microprocessor refers to a system that uses only one silicon chip. Some devices that use only one silicon chip include cameras, phones and digital watches. Co-processor chips however are integrated circuits or multiple chips that assist the CPU with the processing tasks at hand. An example of a co-processor is a mathematics co-processor that formulates mathematical calculations.
26.   There are 5 key components of the CPU. Please describe them below (see p. 260, Table 8.6)
CPU components:
Register
An electronic circuit capable of temporary storing binary digits.
Arithmetic logic unit
A digital circuit that performs integer and logical operations.
System clock
Represents a computers notion of the passing of time.
Control unit
A component in which directs and controls all operations of the processor.
Buses
Wires that transfer signals containing data between components of the computer or several.

27.   Include a picture of the CPU's components below. There is a diagram on p. 259 (Fig. 8.25) that you can use, or you can use a similar diagram that follows.


BUSES
 
Description: http://yoram.info/ICE/images/Pictures%20and%20Diagrams/020%20020%20030%20CPU.jpg

System clock
 
Description: http://tieupworld.com/wp-content/uploads/2013/04/real-time-OS.png
29.   Software is used to control robots. Identify 3 types of software that is used to control robots and give an overview of the software. Lego NXT can be one example, see http://en.wikipedia.org/wiki/Lego_Mindstorms_NXT
Lego Mindstorms NXT- Is a software package that enables a user to program and write instructions for the NXT brick in what tasks and steps to follow. E.g. Move forward and then turn right. The written code containing the steps in which the robot has to follow is then downloaded via USB or Bluetooth onto the brick in which then takes the input data and then performs the output tasks.
Microsoft Robotics Developer Studio- a Windows based platform that is purpose to achieve robot control and simulation. Microsoft Robotics Developer Studio provides a wide range of support application that makes it easy to develop robot code including a program model in which the user can follow in order to achieve successful robot control and simulation. The Microsoft Robotics Developer Studio uses a programming framework that can be used and applied to program a wide range of different robots.
OpenRDK- OpenRDK is a modular software framework that is focused on development of commercial robotic systems that has been targeted to many professional robotic companies in countries such as Italy and Spain. OpenRDK has been applied in many diverse applications with heterogeneous robots with very unique applications.

30. Provide an overview of a PLC

PLC, also known as a programmable logic controller is a digital computer used for automation of electromechanical processes. PLC’s are designed to perform multiple input and output arrangements with extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs that control the PLC’s in which are operated by humans are stored in the non-volatile memory.

31. Give 3 examples of where PLC's can be used.

-Assembly lines
-Amusement rides

-Light fixtures

AUTOMATED CONTROL

SECTION 4: AUTOMATED CONTROL
19.   Provide an overview of automated control.
Automated control is the mechanised command of a task or several tasks. The machine that controls the commands and operations are most often computers using programs that provide instructions of how to produce the output required based on the input instructions.
23. Provide an overview of Traffic Light sensing devices and relevant pictures
Traffic light sensors use computer tracking devices to carry out their operations. Input comes from sensors that are installed under the road that monitor vehicle activity. Cars that travel over the sensors is counted by the sensor and then the traffic signals are changed based on and to meet the changing traffic patterns on the road. The sensors are wired loops that contain a electromagnetic field that are linked to the electrical meter. Maintenance is needed for the traffic light sensors and when a sensor does become faulty it must be attended to. SCATS (the Sydney Coordinated Adaptive Traffic System) professionals are responsible for repair of these sensors in which they fix the problem via the system computer.
Description: http://static.ddmcdn.com/gif/red-light-camera-loop.gif
24.   Provide an overview of actuators and sensors to open and close doors. Please add relevant pictures. (p. 266)
Automated doors that open and close are controlled by sensor that detect movement in which the motors (displayed in the picture) then carry out the tasks of either opening or closing the door, allowing the person(s) to pass through. There are a range of sensors that are used on automatic doors including motions sensors that use infra-red beams in which detects when the beam is broken, pressure sensors that use under mats that use under mats that measure weight is placed on it in which activates a switch opening the door. In the case of automated doors, actuators are used to carry out the action needed that is in response to a signal given by the sensor.
Description: http://www.mpkcontrols.co.uk/wp-content/uploads/2013/02/Combined-photo.jpg

Description: http://www.dsdal.co.uk/images/Actuator3_h255.jpg

FUNCTION OF ROBOTS, SENSING DEVICES AND ACTUATORS

SECTION 3: FUNCTION OF ROBOTS, SENSING DEVICES AND ACTUATORS
1.       What is meant by 'Degrees of freedom'? Ensure you include a diagram to highlight your understanding. (p. 253)
‘Degrees of freedom’ is meant by the number of different ways an appendage can pivot with the term relating to the amount of movement is built and utilised within the nature design. An example of this is below in this robotic arm with the base of the robot (moving mechanism) having the ability to move remotely in any direction and for the arm mechanism to rotate its arm 360 degrees.
Description: http://www.robotgear.com.au/Cache/Files/ProductImageOriginals/1012_Dagu%206%20degree%20of%20freedom%20robot%20arm%20-%20example%20use.jpg

2.       There are 5 general input devices used in robotics. List them below. (p. 254)
1.       Digital camera
2.       Keyboard
3.       Light pen
4.       Mouse
5.       Microphones 
3.       Sensors are a common input device on robotics. Complete the following table (see p. 254 to 255)
Sensor Name
Description
Examples of use
Potential Issues
Thermostat


Switch that opens at a set temperature and stays open while the temperature remains at that level or higher.
Ovens, hot water services
Cheap but not as accurate/responsive as other senses.
Thermistor


Measures temperature continually as resistance: when the temperature increases the resistance drops.
Microwave ovens and air conditioners
Cheap and also similar to thermostat.
Semiconductor


Are sensor materials that have electrical conductivity to a degree between a conductor and an insulator.
Transistors, solar cells and LED lights.
Expensive but efficient.
Light


Detect changes in the level of light. They collect data related to the intensity of light of an image and then convert it to a digital form.
Barcode scanners, burglar alarm
It is harder to convert more complicated images into digital form.
Position


A sensor used to monitor and track the relative position of objects around it.
Ultrasonic sensor and proximity sensor
The machine operates to a very accurate extent but the machine could fail. A repair of a position sensor is not easy.
Potentiometers


Sensors that are used to determine rotation measuring electrical resistance with a meter showing the amount of voltage at a particular point.
A video game joystick and a remote control
Overheating and wrong readings. Environment could have an effect on the reading. For e.g. Wind and rain.
Sonar



Sonar sensors are used to detect sound underwater to discover the position of an object in the water.
Submarines and boats.
Can have some harm to marine mammals such as whales.
4.       Define and compare an Actuator to a Sensor
A sensor is a device that converts input from the environment into a signal that can be communicated to a control system. An actuator however is a specialised hardware device which, under control, comes out as mechanical actions. The differences between a actuator and a sensor is a sensor controls the input into a robotic system however the actuator then receives the input and then creates the appropriate output responses.  Actuators work on performing the work from the measured inputs by powering the system such as electrical and hydraulic power however sensors focus on measuring the data from its environment such as temperature, light, touch, sound etc. Actuators also produce mechanical actions but sensors focus on converting an input into a signal that then leads to an output, carried out by the actuator.
18. Actuators are a common output device on robotics. Complete the following table (see p. 256)
Output devices
Description and main feature
Advantage
Disadvantage
Speakers



Is an external hardware that produces sound from a computer through a 3.5mm stereo jack. The main feature is the speaker’s volume control.
Normal speech rather than synthesized speech is possible
Require extra hardware e.g. sound cards
Display (CRT or LCD)


Is an output surface that projects mechanisms that show text, images, animations etc. The main feature of an LCD display is that they are available for many applications.
No waste of paper and instead can be interactive or display animations.
No hard copy (ie. printed page)
Solenoids
(an actuator)


A cylindrical coil of wire acting as an electromagnet when carrying electric current. It uses the electromagnet to move an arm or plunger through a small movement.
High reliability and limited pressure drop.
Control signal must stay on while in operation.
Stepping motors
(an actuator)


A motor that moves and rotates in small, discrete steps. It also uses electromagnets with it utilizing a shaft that makes the motor turn.
Needs no feedback
Has low efficiency.
19.   Define Primary Storage and provides examples (p. 257)
Primary storage is a device that holds data for processing, processed data waiting for output and instructing for processing. Primary storage is found in the motherboard where it is linked to the processing parts of the computer such as the CPU and GPU. Some examples of primary storage are ROM and RAM.
20.   Define Secondary Storage and provide examples
Secondary storage is any storage device that is located outside of the CPU (central processing unit). This type of storage is not essential to the operation of the computer but is used as a peripheral to hold information and store data that can be accessed from the computer. Secondary storage also is not the main memory of the computer. Some examples of secondary storage are hard disk drives, DVD’s and portable flash drives.
21.   Using the following diagram, write below what each letter represents. You will find an overview of this motherboard at http://www.build-your-own-computer.net/motherboard-diagram.html
Description: http://www.build-your-own-computer.net/image-files/motherboard-diagram-01.jpg
























A-     PCI Slot         B- PCI-E 16x Slot   C-  PCI-E 1x Slot        D- Northbridge        E- 4 Pin Power Connection  F- CPU-Fan connection    G-  Socket   H- Memory slots   I- ATX power connector  J- IDE connection    K- Southbridge  L- SATA connections   M- Front panel connections  N-  FDD connection   O- External USB connections     P- CMOS battery