Unit 57: Mechatronic System

Unit 57:
Mechatronic System
Unit code: F/601/1416
QCF level: 4
Credit value: 15
OUTCOME 3
TUTORIAL 1 - SYSTEM DESIGN
3
Be able to produce a specification for a mechatronic system or mechatronic product
Standards: standards e.g. appropriate British, European and international standards. Required sensor
attributes: phenomena being sensed; interaction of variables and removal of undesired changes;
proximity of sensor to measurand; invasiveness of the measurement and measurand; signal form;
ergonomic and economic factors
Actuator and sensor technologies: selection of suitable sensor and actuator technologies for
mechatronic systems and mechatronic products
Controllers: selection of appropriate computer control hardware for mechatronic systems and
mechatronic products e.g. microprocessor, PLC, PC-based, PlC, embedded controllers
Pictures used in this tutorial are from various sources and may be copyright protected. Contact
[email protected] if this causes any problems.
Assessment of this outcome is best done with a suitable assignment.
CONTENTS
1. Introduction
2. Standards
3. Sensor Attributes
 Passive or Active.
 Analogue or Digital
 Size
 Proximity to Measurand
 Temperature
 Speed of Rotation
 Proximity Detector
 Speed of Response
 Pressure Sensors
 Self Calibration
 Choosing a sensor
5. Design and Programming Hardware and
Software.
 Control Hardware
 Peripheral Interface Controllers
(Pics)
 Software
 Plc Simulators
6. Case Study - A Gyrobot
4. Actuators Choice of Technology
 Hydraulic
 Pneumatic
 Electric Motors And Actuators
 Other Actuator Designs
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1. INTRODUCTION
Taken at face value, this outcome appears to require a student to have a wide range of detailed knowledge of
all the engineering disciplines covered by mechatronics. In reality a mechatronic design is likely to be
created by a team from different disciplines working together but all having a good understanding of the
other disciplines. The learning outcomes required are listed below. It has to be assumed that students have a
good knowledge of Mechanical Engineering, Electrical/Electronic Engineering, Fluid Power and
Programming Techniques. This tutorial can only provide a broad guide to show how you might achieve
them.
Learning Outcomes for Outcome 3
3.1 produce a specification for a mechatronic system to meet current British Standards
3.2 select suitable sensor and actuator technologies for a mechatronic system
3.3 specify appropriate computer control hardware for a mechatronic system
2. STANDARDS
The importance of international standards in each discipline should already be known to you. Very little
information will be found if you search for international standards specifically for Mechatronics but some
that are relevant are mentioned later in the tutorial. Standards are important in the design process to ensure
that:
 Components fit and match each other
Examples: shafts, couplings, flanges, plugs, sockets, cables, pipes and so on.
 Components perform correctly as predicted
Examples: speed, torques, force, strength, insulation, reliability and so on.
 Electronic systems communicate with each other correctly
Examples: Digital and analogue protocols, signal standards, programming and so on.
 Drawings, circuits, block diagrams, flow charts and so on are understood by every one by
conforming to the same standard.
 Designs and circuits produced in different software suites can be exported to other software suites,
e.g. importing mechanical 3D models into other programmes to analyse the stress and dynamics.
 Designs of the mechanical, electronic and control systems can be exported into robots, PLCs, PICS
and NC Machines (for making parts).
The standards covering all these are many. The main body for international standards is the ISO
(International Standards Organisation), the IEC (International Electrotechnical Commission) and the ITU
(International Telecommunication Unit). ISO and IEC have formed joint committees to develop standards
and terminology in the areas of electrical, electronic and related technologies. The three organisations
together comprise the WSC (World Standards Cooperation) alliance. National standards organisations
usually comply with the international organisations. Here is a list.
BIS
BSN
ABNT
AENOR
AFNOR
ANSI
BSI
DGN
DIN
IRAM
BSJ
ICONTEC
ILNAS
JISC
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India
Indonesia
Brazil
Spain
France
U.S.
U.K.
Mexico
Germany
Argentina
Jamaica
Colombia
Luxembourg
Japan
KATS
NEN
SABS
SAC
SCC
SIS
SFS
SN
SNV
SNZ
UNI
SAI
Sirim
Korea (Republic)
Netherlands
South Africa
China
Canada
Sweden
Finland
Norway
Switzerland
New Zealand
Italy
Australia
Malaysia
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3.
SENSOR ATTRIBUTES
Outcome 2 covered the basic types and operating principles of various sensors. The student needs to be
knowledgeable about all aspects of sensors in order to choose and specify appropriate sensors for the design.
Here is a reminder of what you should know from outcome 2.
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Measurand: things to be measured
Movement and angle
o Voltage, current
Velocity and acceleration
o Magnetism
Direction and location
o Frequency
Force, torque, and pressure
o Dimensions
Proximity and contact (touch)
o Hardness
Flow
o Acidity (pH)
Viscosity
o Weight, volume
Density
o Humidity
Temperature
o and many more
Light level
Sound
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Basic principles:
Resistive
Capacitive
Inductive
Ultrasonic
Piezoelectric
Piezoresistive
Light
Radiation, Infra-red, X-ray
Smart material sensors and
more
Other attributes to be considered are:
Passive or Active.
 Passive sensors require no external power (e.g. some thermometers and light cell)
 Active sensors require external power source (e.g. Strain gauge).
Analogue or Digital
 Analogue sensors produce continuous signals such as a current (e.g. 4 - 20 mA standard) or air
pressure (e.g. 0.2 - 1 bar standard).
 Digital sensors produce signals as binary numbers. This can be inherent in the design but normally
requires an Analogue to Digital converter (ADC). You might consider sensors with simple on or off
action as digital (e.g. proximity detectors).
Size
In many mechatronic designs it is advantageous to use very small sensors that can be integrated into a
circuit or structure. These are micro- and nano-sensors. They are very useful for building compact systems
with built in signal processing (such as ADC) and automatic calibration which might need a built-in micro
actuator. In this context you come across the terms MEMS which means Micro-Electro-Mechanical
Systems. This is a technology defined as miniaturized mechanical and electro-mechanical elements that are
made using the techniques of micro-fabrication.
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1. A tilt sensor module that provides a digital level output if tilted beyond a preset level. Typically these are
used in games controllers whilst larger versions are used in vehicles such as measuring the pitch and roll
of a ship.
2. A flow cytometer widely used for analysing microscopic particles such as cells and bacteria and they are
used in medicine, life sciences and environmental metrology.
3. A Micro-mechanical accelerometer measurement system on a single monolithic IC. Typical uses are
vibration detection, game controllers, robots or anywhere you need to obtain motion-sensing &
orientation information.
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Proximity to Measurand
The type of sensor is often dictated by the distance to the target (measurand) and its obtrusiveness to the
measurand. Here are some examples to explain it.
Temperature
Consider a sensor for measuring very hot temperatures. This might
destroy the sensor unless it is protected and this will make it slow
to respond (e.g. a thermocouple in a ceramic sheath pictured).
A solution would be an optical pyrometer typically as shown. This can be sited some
distance from the target and have a response time of typically 6 ms.
Speed of Rotation
The speed of rotation can be measured in various ways. Some tachometers need to be attached to the
rotating body. Others have to be placed very close and some not close at all.
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1 - Motor with attached analogue tachometer.
2 - Hall Effect Tachometer - the sensor has to be close to the rotating body and operated by changes in
magnetic field.
3 - Optical tachometer sensor head can be placed up to 1 m from the target and works on reflected light
pulses.
Proximity Detector
Proximity detectors have a wide range of applications and detect if an object is present or not.
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1 - A magnetic type sensor that fits on the outside of a pneumatic cylinder and is activated when the piston
inside passes it. Typically used to trigger signals to a controller and activate the next action.
2 - A magnetic type typically used to detect a hydraulic clamping cylinder has completed its action.
3 - An optical type on a chip. Typical uses are: to disable the touch-screen on a cell phone, to enable a
speakerphone automatically, to operate a menu pop-up automatically and to sense when someone
places their eye to the viewer of a digital camera.
4 - An optical type for sensing objects from some distance such as items on a conveyor.
5 - A capacitive type that detects materials a magnetic type will not.
6 - An ultrasonic proximity detector that works up to 6 metre from the target. It has advantages over other
types.
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Speed of Response
All sensors have a time lag between a change in the measurand and a change in the output. The section on
temperature sensors mentioned this. Response Time is often defined as the time for the incremental change
in the output to go from 10% to 90% of its final value when subjected to a sudden change.
The response of the sensor has to be appropriate for the task. Most sensors based on electrical technology
are fast. Sensors, for example, used in combustion engine management systems have to be fast in order to
make the engine run properly. Here are some examples.
Pressure Sensors
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Pressure sensor with a rise time of <3 μs for measuring fast pressure rises in shock waves.
Manifold Absolute Pressure sensor (MAPS) typically have a response time of 1 ms. They are built on a
chip that puts out a voltage proportional to engine vacuum, from zero to 5 volts. The computer uses the
voltage to decide if the throttle is open and how far, so it can adjust the fuel mixture.
A pressure sensor used for barometric pressure measurement does not need to be fast and this one has a
rise time of < 100 ms.
Self Calibration
Measurement systems are prone to errors over an operating life time due to drift. The zero point might need
to be reset and the gain adjusted. Some sensors are able to automatically calibrate/recalibrate themselves.
This can be useful when unexpected disturbances upset them. The system used might be a software solution
or it might involve moving the sensor to a calibration point.
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Auto-calibrating line sensor for detecting lines 1cm to 3cm wide and determining dark colour or bright
colour line. With 1 press, it will start "recognizing" the surface under it, calibrating the threshold between
dark and bright. it takes 4 to 5 seconds only. After that, it is done, being stored in internal non volatile
memory.
CO2 sensor for use in biological or scientific applications. It is capable of performing a complete function
check of the sensor module.
A board mounting differential pressure sensor that enables a designer to use an algorithm to set the
compensation, calibration, and amplification while allowing the flexibility of self-calibration.
Choosing a Sensor:
 Determine the variable to be measured
 Determine the range over which it needs to be measured
 Determine the speed of response needed from the sensor (time lag)
 Bearing in mind the electronic systems used, decide whether you need analogue or digital outputs
 Have a good idea of the size limitations and physical attributes needed to assemble and integrate the
sensor
 Decide the proximity of the sensor to the target being measured.
 Consider the energy requirements for the sensor.
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4.
ACTUATOR CHOICE OF TECHNOLOGY
The various types of actuators likely to be used in mechatronics were covered in outcome 2 tutorial 3. These
were either Electric or Fluid Power (hydraulics and pneumatics). Usually the choice is fairly obvious for the
tasks required of the system but sometimes the decision needs more consideration. The main attributes of
the actuators that need to be considered are:
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The size of the operating forces and torques
The operating environment
Linear or rotational movement?
The energy source
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Speed of response and motion
The amount of movement needed
The degree of precision needed
The method of control and monitoring
Hydraulic
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ADVANTAGES
High force and torque
High power to weight ratio
Linear and rotational actuators
High precision
Good low speed characteristics
Safe when the actuator jams (stalls)
Good in harsh environments
DISADVANTAGES
 Relatively expensive
 Requires a pumped fluid supply
 Requires rigid and flexible high pressure
supply pipes and low pressure return pipes
 Motion relatively slow but response is fast
 Fluid might be a hazard and messy
 Requires associated valves to control the
motion
 Pumping system runs continuously and
energy is used even when actuator is not in
use.
Hydraulics is chosen for applications needing high pressure and firm precise motion. Examples are
industrial robots, aircraft systems, marine uses (e.g. stabiliser systems), heavy duty precision machining,
large vehicles and so on. They are the only choice for use under water because designing and making sealed
electric motors is costly and requires substantial engineering. More examples are shown below.
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1. Typical hydraulic power Pack
2. A small hydraulic motor 45 mm diameter and produces 17 N m torque.
3. A heavy duty hydraulic motor producing 1785 N m torque
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1. Hydraulic cylinder with stroke of 7 mm and thrust of 1.7 kN
2. Hydraulic cylinder for marine applications capable of a 24 metre stroke
3. Heavy duty industrial robot with hydraulic actuators
4. A rotary hydraulic actuator for robot joints
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Pneumatic
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ADVANTAGES
Medium and low force and torque
Linear and rotational actuators
High relative speed
Micro actuators available for small
applications
Do not need return pipes as used air is vented
Relatively cheap
Safe when the actuator is jammed (stalls)
Clean and easy to maintain
Safe in explosive environments (APEX
compliant)
Motors are light and compact compared to
electric motor.
Motors are robust and highly durable under
extreme operational conditions
Rodless cylinders possible with pneumatics
only
DISADVANTAGES
 Time delay at start of motion due to
compressibility of the air.
 Precision more difficult to obtain
 Requires a compressed air source, usually a
ring main
 Dangerous at high pressure
 Requires associated valves to control the
motion
 Only safe at low pressure
 Air compressor runs continuously so energy
is used even when the actuator is not in use.
 Air leaks tend to be ignored and this is costly
Pneumatic actuators are chosen where high pressure systems are not needed and precise motion is not
needed. They are widely used in production lines for moving things, diverting things, opening and closing
things and so on. Air is the choice for tools such as drills, grinders, riveters and so on because they are safe
when they jam. Electric actuators are expensive if they are manufactured to work in dangerous
environments such as dusty or other explosive atmospheres. Pneumatics is the best choice as they are
cheaper and safe. Here are some examples.
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1. Pick and place robot not requiring high precision
2. Deburring tools for use on robot arms
3. Suction Pads for lifting light objects
4. Clamping Cylinder
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1. Air motor with gears for driving many types of machines
2. Air motor for driving a conveyor belt system
3. Stainless steel motor for use in acidic environment
4. Milling robot for drain restoration with air motor
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Electric Motors And Actuators
ADVANTAGES
 Very versatile ranging from very large to
very small
 Electric power sources are can be mains
supply or battery
 Wide range of operating characteristics some
with precise motion control
 Easiest to integrate into compact systems
 Control equations usually simpler as the
system is more linear
 Energy is only used when the actuator is in
motion
 Clean and relatively easy to connect
DISADVANTAGES
 Heavy duty motors are bulky
 Mechanical motion converters often needed
(e.g. to produce linear motion)
 Burn out if the motor stalls
 Become expensive if they need protection
from harsh environment e.g. salty damp
atmosphere
 Hazards associated with electricity (e.g.
sparking of fires and explosions in certain
environments)
 For demanding applications that require
extremely high torque, electric motors
become too costly and too bulky because of
the large number of windings needed
Actuators are widely used in systems where the flow of a fluid through a pipe needs to be controlled and
adjusted. This might involve changing from open to closed or accurate positioning of the valve spindle.
Here are some examples.
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1. Electric Actuator for operating flow control valves
2. Electrically operated valve
3. Linear electric actuator with many uses similar to a pneumatic cylinder.
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Electric motors have been described in more detail in outcome 2. They are used for many applications from
very large to very small. Here are some examples.
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1. Electrically powered drone
2. Robot arm with electric servo motors
3. Large DC drive for rolling mill
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Other Actuator Designs
Ultrasonic Motor
Ultrasonic Motor (USM) harness ultrasonic oscillation from a piezoelectric element. They are mainly used
in camera mechanisms to focus the lens. This technology makes focusing precise, virtually noiseless and
incredibly quick – some lenses focusing literally faster than the human eye. The picture below shows the
motor and gearing used in a camera.
Electromechanical Solenoids
These devices are basically electromagnets which when energised cause the iron core to move. They are
used to produce limited linear movement and are ideal for operating mechanisms that only need to operate
between two limits. They are digital devices either on or off and so relatively easy to use in a control
system. Typical uses are:
Electrically operated fluid control valves (hydraulic and pneumatic valves)
Gaming devices such as a pin ball machine
Dot matrix printers
Fuel Injectors
Starter motor switch
Electrical relays
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1. Engine Solenoids
2. Solenoid operated valve
3. Solenoid operated pneumatic valve
4. Solenoid operated fuel injector
Muscle Wire
This is a smart metal that "remembers" its original shape and when deformed it
will return to its previous shape when heated. Basically a wire device can be
made to bend or contract and this has applications for things like robot hands
where the fingers can be made to move. It is basically a solid state device that
can produce linear movement in response to an electric current.
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Rodless And Double Rod Designs
Rodless cylinders are only possible with pneumatic cylinders. You will have to look elsewhere for details of
the operating principle but basically the moving piston inside is attached to a carriage on the outside which
slides back and forth along the cylinder. These are very versatile actuator that can be used to operate many
kinds of mechanism such as picking and placing with a suction cup.
Rodless Pneumatic Cylinder and a pick and place robot using them
Double rod cylinders have the same kind of versatility where the rod is clamped and the cylinder body
moves. These are used in hydraulics and pneumatics and are often used to move platforms.
Double rod cylinders pneumatic left, hydraulic right.
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5.
DESIGN and PROGRAMMING HARDWARE and SOFTWARE
In this modern era it is almost unthinkable that some of the most complex mechatronic systems can be
designed and then controlled without the use of advanced software programmes. Software is used to:
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produce a 3D design of the mechanical system
design and model the different control system algorithms
design the electronic and/or fluid power circuits
simulate and test the overall model for performance
identify and select electronic components for the real system
After this stage you need to:
 identify and specify real sensors and actuators that meet the requirements
 identify and specify mechanical components
 build and test prototype
One computer programme that does all this is known as ADAMS (Automatic Dynamic Analysis of
Mechanical Systems) from MSC Software. This is a Multi-Body Dynamics (MBD) simulation programme.
With this you can study the dynamics of moving parts and how loads and forces are distributed throughout
mechanical systems.
This programme also enables you to merge your mechanical design with control and electronic designs
created on other software packages such as MATLAB® and Easy5®.
Adams/Mechatronics is a plug-in to Adams which can be used to easily incorporate control systems into
mechanical models. Adams/Mechatronics has been developed based on the Adams/Control functionality
and contains modelling elements which transfer information to/from the control system.
Visit this web site to see simulations of complex systems like the moon rover.
http://www.mscsoftware.com/product/adams
Many other suites of software are available for designing such as:
Circuit Wizard http://www.new-wave-concepts.com/ed/circuit.html
Genie Design Studio http://www.genieonline.com/
Mplabs
Automation Studio™
Multiprog
You will find more on this in the PLC module unit 22 outcome 4.
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Control Hardware
When deciding what kind of electronic system to use for controlling the system you should consider:
 Is the system compact enough to integrate the electronics within the main electronic circuit such as
with a peripheral interface controller (PIC)?
 Is the system robust and suited to being controlled by a unit such as a programmable Logic
Controller (PLC)?
Peripheral Interface Controllers (PICs)
These are advanced microcontrollers developed by microchip technologies. They are sometimes called a
computer on a single chip but might be best thought of as a PLC on a single chip. The programme to
produce the required control function is developed and loaded into the chip. The chip is then embedded in a
machine or device to control it. Shown is a chip and test board to enable it to be programmed and tested.
Examples of machines that use them are:
Cameras/Camcorders
TV controllers
DVD Players
Microwave Ovens
Printers/Scanners
Keyboards and Mouse
Modems
Motor cars
Medical devices
Toys
Robots
Mobile Radios/communication devices
Vending Machines
….. and many more
The largest single use for microcontrollers is the automobile industry where they are widely used for
controlling engines and power controls in automobiles. In industry they are usually set up to carry out a
dedicated control function in a variety of processing/manufacturing systems. They are expected to be
durable and to work for a long time. They are used widely to control individual items like conveyor belts
largely independent of the main system but linked into the overall control system. They are embedded in
some instruments to perform on the spot control and are interrogated by the main controller.
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Software
The following describes some of the software available for programming your control system
Circuit Wizard http://www.new-wave-concepts.com/ed/circuit.html
You need a computer to run this software. It allows you to program a PIC microcontroller circuit. The
computer will need a serial port or a USB port. This is used to connect the computer to the microcontroller
circuit. For educational use Genie Design Studio is a version of the same software.
Genie Design Studio http://www.genieonline.com/
This is software for programming GENIE microcontrollers. Its powerful language and highly graphical
interface make the whole process of developing electronics-based projects quick and easy. You construct a
flow chart by dragging and dropping commands from the library.
By double clicking on the box you can set labels, timers and input/output designations available on the
selected chip. This replaces numerous lines of text programming code and means that a program can be
written quite quickly, with fewer mistakes. It is then simulated on the screen to check that it works. The
program is finally downloaded to a GENIE microcontroller. The circuit board design is also shown and if a
suitable socket is added to connect it to the computer, the chip can be programmed on the board. The
following shows a flow chart and circuit from the screen. The circuit can be tested by simulating on the
computer.
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MPLABS
This is free very advanced programming/debugging software for a wide range of Microchip’s more than 800
8-bit, 16-bit and 32-bit MCUs and digital signal controllers, and memory devices. The screen dump below
shows that you need to be a serious programmer to use this.
See also PICkit™ 3 which is a kit to enable a chip content to be examines and debugged.
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en538
340&redirects=pickit3
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PLC Simulators
It is usually best to adopt any software and simulator hardware recommended by the manufacturer of the
PLC chosen but there are graphic programmes that enable you to design and test circuits and then convert
them into a form suited for a given PLC.
Automation Studio™
This is a professional suite of programmes allowing the construction of electric, electronic, pneumatic and
hydraulic circuits (Mechatronics) and their associated PLC control circuit in Ladder programming or
Grafcet/SFC programming. Automation Studio™ can import SFC/Grafcet codes either in XML or in
Cadepa™ software format. It also allows you to export SFC/Grafcet into Siemens™ S7 PLC and XML
format. The circuit is simulated on screen and transferred to the PLC through an interface. It can also be
used to control hardware directly through a suitable interface making the computer into a PLC. The diagram
shows a circuit and SFC programme.
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Mitsubishi/Melsec
With the appropriate hardware to connect the
PLC to the computer, programmes can be
created, tested, simulated, downloaded or
uploaded from the PLC and the PLC can be
monitored when running.
The diagram below shows a typical programme
designed with the software.
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Rslogix 500 Software
The RSLogix software is a design studio using ladder logic programme compliant to IEC-1131.
It is designed to be used for the Allen-Bradley SLC 500 and Rockwell MicroLogix family of processors.
Multiprog
This is a programming suite from KW Software. Details may be found at this link.
https://www.kw-software.com/en/iec-61131-control/programming-systems/multiprog-5
This software allows programmes to be produced using any of the five programming systems defined in the
international standard IEC 61131 and explained in outcome 3. Apart from the actual programming function,
a modern programming system provides a broad range of intelligent additional functions, which support
programmers in developing, testing, and commissioning their application. It takes care of the project
management and helps with the management of fieldbuses, networks and peripheral components.
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CASE STUDY - A GYROBOT
This is based on extracts from a published project to design and test a GYROBOT. You will find the full
article at this web link. www.s2is.org/issues/v2/n2/papers/paper1.pdf
A Gyrobot is a single wheeled vehicle that must roll in either direction and also steer left or right.
Propulsion is by turning the axle with the drive motor. Control is by a radio link.
Basis of the Design
The wheel is basically a hollow shell with a tyre around it. This is modelled with the Adams software or
imported into Adams from other programmes such as Autocad ® or SolidWorks®. The wheel will be driven
by rotating the axle with a motor and drive belt mounted on a platform. The platform will be supported on
the axle and kept roughly horizontal by the suspended weights below it. Rotating the axle will also try and
rotate the platform the opposite way by reaction torque so this is applied by the suspended weights.
A flywheel is suspended below the platform and made to spin by the spin motor. The speed will be
controllable between 1000 and 7000 rev/min. The flywheel keeps the wheel balanced through gyroscopic
torque. The flywheel is mounted on a 2 axis gimbal. If it is tilted by the tilt motor, gyroscopic torque makes
the wheel turn about the vertical axis and it will lean into the turn through gyroscopic torque produced on
the wheel but only if it is revolving (like leaning over on a bicycle).
The electronic module will contain the battery pack, radio link, programming system and the controller. The
controller will control the motors based on the control programme.
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Produce a 3D model of the system (outline design shown above).
Import it into the Adams programme
Produce a control model for controlling the motor speeds
Test the computer model by running the flywheel and drive motor and operating the tilt motor. If
necessary make adjustments to the flywheel mass or any other corrections to the design.
When a satisfactory performance has been obtained then a detailed design must be produced. The
component parts must be specified, obtained and assembled. The Gyrobot should be ready to go and it
should work first time if all has been done according to plan. Put this way it all seems simple but when
producing the detailed design there is a lot to be done.
You will need appropriate types of motors to produce the required speeds and torques and this may require
some form of speed reduction or increase e.g. with drive belts and pulleys or built in gears. The tilt motor in
particular will only have to produce a small rotation so probably a stepper motor or other servo motor.
The electronics would have to be compact so probably a PIC system would be best. If feedback is to be used
in the control system (closed loop system) then appropriate sensors would be needed to measure the angles
and speeds.
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SELF ASSESSMENT EXERCISE
The Gyrobot outlined is to be steered remotely and its speed varied remotely.
List the things that need to be sensed.
Suggest the best type of sensor for each application giving your reasons.
List the actuators that are needed.
Suggest the best actuators for each application and give your reasons.
Outline a control programme using any suitable graphics.
Outline an electronic design using any suitable graphics.
Describe the best hardware for implementing the control.
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