Systems Approach /Modeling and simulations in Matlab - Example
A six degree of freedom robot manipulator is developed for pick and place operations in a factory
as given in Figure. Assume that the basic mechanical and electrical designs were already
completed. Each joint consists of a DC motor as the actuator and an encoder to get the angular
feedback. The motor controller drives the six motors to position the end effector to the target
position. Further, the robotic system includes an user interface with a keypad and a LCD display
to enter target positions.
Answer following questions based on the above-mentioned example.
a) Considering the overall system,
i). List the functional inputs and outputs of the robot
•
•
Inputs – Target position by keypad, angular feedback
Outputs – Angular rotation of DC motors
ii). List the functions of the robot
•
•
•
•
Taking given position details
Converting position details to servor commands
Taking continuous feedback of angular placement.
Picking and placing at given position
iii). Explain the function of the system by considering an example scenario.
•
This is a common type of system in industry. Its basically replaces to Man power by
machine to take an item from place and placing in another. In car assembly we can see
parts of the car picking up from one place and placing at the given position really helps
to lift heavy weights and reach difficult places.
b)
i). Identify the platform as a system of systems and list the subsystems
1.
2.
3.
4.
User Input management system,
Read and process,
Command generation,
Pick and placement
ii). State the functionality of each subsystem
1. User Input management system – Reading place commands from the user through the LCD
2. Read and process – Check the validity of input and store in data base and send to command
section
3. Command generation – Convert place command in to servo angle commands
4. Pick and placement – functioning motors according to the command
iii). Sketch the system block diagram and label each subsystem
User Input
Digital signals
Read and
process
Command
generation
Angular data from
encoders (analog)
Generate analog
signals
LCD Display
Pick and
placement
Function Motors
according to
analog signals
Digital signals in
to analog systems
iv). Clearly mention details of the interconnections (type of signals/ interfaces/ conversions)
between each subsection on the same sketch (in part b)-ii)).
c) Considering the functional details of the system, Sketch the functional flow of the overall
system as a flow chart.