Organized By:
Sponsored and Prepared By:
San Diego State University
Parker Suggs – Project Manager
Colin Fera – Website Designer
Lee Xiong – Online Document Manager
Justin Christopherson – Parts Coordinator
Daniel Renteria – Technical Illustrator
Luan Truong – Power Point Illustrator
Chris Dansalan – Editor of Reports
Page | 1
Organized For:
Dr. R. Lal Tummala
Department Chair
SDSU College of Electrical Engineering
John Kennedy
EE 490 instructor
Table of Contents
Table of Contents.................................................................................................... 2
Introduction ............................................................................................................. 3
Abstract .................................................................................................................. 3
Product Description ................................................................................................ 3
Design – Block Diagram ......................................................................................... 4
Figure 1 – Functional Block Diagram...................................................................... 4
Figure 2 – Microcontroller Diagram ........................................................................ 5
Design ...................................................................................................................... 6
Specifications ......................................................................................................... 6
Design - Mock-up Illustration ................................................................................. 7
Figure 3 – Illustration of Chassis (detailed) ............................................................ 7
Figure 4 – Illustration of Chassis (CAD) ................................................................. 7
Figure 5 – Top view of Chassis .............................................................................. 8
Figure 6 – Side view of Chassis ............................................................................. 8
Testing and Verification ......................................................................................... 9
Testing and Verification - Benchmarks ............................................................... 10
Project Management – Project Plan .................................................................... 11
Budget – Project Cost Analysis ........................................................................... 12
Figure 7 – Project Cost Analysis .......................................................................... 12
Promotional Flyer ................................................................................................. 13
Figure 8 – Promotional Flyer ................................................................................ 13
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Introduction
Abstract:
Our LoCo P.N.P. product is a Pick and Place robot that fulfills the functionality
of high end SMD systems at a tenth of the cost. A typical PCB assembly line can
range from $100k to upwards of a million dollars. Additionally, the low cost pick and
place machines starting to appear are often problematic, contain poorly documented
software and hardware, and are often supported by just a single manufacturer. Our
objective is to design and construct an open source machine that will embed specific
advantages for both software and hardware components. Software will be freely
available and adaptable so fixes and modifications can be dealt with in an
appropriate manner. Moreover, hardware will be commercial off the shelf (COTS)
whenever possible for ease of replacement. This will reduce unnecessary repair
time and cost, at the same time minimizing dependency of a single manufacturer.
Product Description:
The purpose of this project is to contribute to the community effort in
designing an open source pick and place robot while building a low cost, efficient
machine to use at San Diego State University. The core structure will be comprised
of a four axes gantry style system composed of X, Y, Z and A. The X and Y axes
deliver linear motion on the PCB plane, while the Z axis provides elevation needed
for retrieving and placing components. Additionally, the A axis will deliver rotational
support for correct alignment of parts. The device will also utilize a camera providing
machine vision feedback to support operations of the A axis and vacuum system.
Parts will be retrieved and released using these systems and de-reeled using a drag
feeder.
The main control of the system will be coordinated by a PC, which
communicates with the motion control system and machine vision camera. The
motion control system consists of an embedded systems microcontroller interfaced
to stepper motor drivers, limit switches, and a vacuum solenoid. The mechanical
aspect of this machine is mainly COTS products, including round shaft bearings,
lead screws, linear bearings, and the chassis. The mechanisms to position the head
will be stepper motors for all four axes. The unit will function comparably to
expensive and high performance machines, yet be built at a fraction of the cost.
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Design- Block Diagram
Figure 1 – Functional Block Diagram; illustrates basic integration of hardware and
control systems.
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Design - Block Diagram Cont.
Figure 2 – Microcontroller Diagram; illustrates basic input/output signals to motion
control systems.
Page | 5
Design
Specifications:
 One Y-direction stepper motor, rather than two, overcomes misalignment
problem
 500 estimated pph(parts per hour)
 800mm x 800mm working area
 Placement of 0402 standard parts
 Optical feedback system for better placement of small parts
 10 feeder reel stock capacity
 Easy to use graphic software for quick programming. Programming can be
done with teaching video camera, on screen Gerber file graphics or CAD file
 110V AC 60 Hz, or 220V AC, 50 Hz, 750 watts electrical
 50 lbs maximum weight
 920mm (w) x 944mm (d) (removable feeder) x 480mm (h)
 Machine customization available
 .05mm precision accuracy on X and Y axes
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Design – Mock-up Illustration
Figure 3 – Illustration of Chassis (detailed)
Page | 7
Figure 4 – Illustration of Chassis (CAD)
Design – Mock-up Illustration Cont.
Figure 5 – Top view of Chassis
Figure 6 – Side view of Chassis
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Testing and Verification
Testing and verification will be an on-going process that parallels system
development. As systems come online, necessary testing will be performed for
correct functionality. The following test bullets are not sequential and may be reassessed during any part of development. Overall, components will be tested at the
lowest level, incorporated into the system, and then verified for proper operations.
 Microcontroller and motor drivers testing
o G-code interpreter (GRBL) – verify interpreter will download to microcontroller
and accept manual inputs via GUI
o Correct operations from manual input – verify microcontroller will output
correct operations when receiving manual inputs from user
o Voltage overload protection – verify microcontroller will engage safety circuits
in the event of an over-voltage condition
o Current limiting requirements – verify correct current limits for motor drivers to
provide nominal motor operations
 Motor testing
o Torque and speed requirements – verify that torque and speed are sufficient
at X, Y, Z, and A axes to meet specifications for parts placement
o X and Y positional accuracy and repeatability – verify motors and linear
systems provide accuracy needed to place head and nose at correct X, Y
locations; consistent results expected
o Z and A positional accuracy and repeatability – verify motors, linear, and
rotational systems provide accuracy needed to place head and nose at correct
Z, A locations; consistent results expected
o Power supply – verify power supplied is suitable for necessary operations
 Head testing
o Correct sensor feedback – verify sensor will stop nose in correct location of
part to be picked up and placed
o Vacuum system and nose operations – confirm vacuum is sufficient to pick up
and release part as necessary; verify sensor operation for vacuum system
o Z and A axes – verify positional accuracy and repeatability for parts pick-up
and placement
o Power supply – verify power supplied is suitable for necessary operations
 Safety systems testing
o Emergency shut-off switch – confirm system halts when shut-off switch is
manually activated
o Temperature control systems – confirm system does not overheat during
normal operations
Page | 9
Testing and Verification - Benchmarks
Benchmarks for the LoCo P.N.P machine include:
 Sturdy frame that is able to support the weight of the head, necessary motors,
wires, and other equipment
 Operational X and Y axes with working motor for each axis and motion across
entire work area
 Operational Z axis with motor
 Operational rotating A axis on the head, with rotation of 180 degrees in each
direction
 Working vacuum pump capable of holding a variety of different components
for placement on a printed circuit board
 Ability for the head to select specific components and place anywhere on
various circuit boards
 Design that is easy to modify or update in subsequent semesters by future
engineering teams or hobbyists
Page | 10
Project Management – Project Plan
Project Management:
Tasks were divided between team members as follows:
 Colin Fera:
Mechanical designer
 Daniel Renteria:
Feeder system and head designer
 Justin Christopherson: Head and power supply system designer
 Lee Xiong:
Microcontroller and Motor Controller Programmer
 Luan Truong:
Microcontroller and Motor Controller programmer
 Chris Dansalan:
Head and power supply system designer
 Parker Suggs:
Sensor and microcontroller designer
The Gantt charts below provide a detailed schedule, responsibilities of each team
member, and project milestones.
Page | 11
Budget – Project Cost Analysis
Quality
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Description
Unit Price Total With Tax Grand Total
Frame Extrusion Components
$200.00
$216.00
$255.00
Misc Frame Hardware and custom Brackets
$100.00
$108.00
$363.00
linear x bearing assemblies
$80.00
$172.80
$535.80
linear y bearing assemblies
$80.00
$172.80
$708.60
Ball Screw X
$120.00
$129.60
$838.20
Ball Screw y
$120.00
$129.60
$967.80
Arduino Mega 2560 R3
$54.95
$59.35
$1,027.15
Nema 17
$15.00
$16.20
$1,043.35
Nema 23
$23.00
$49.68
$1,093.03
grblShield v4
$69.99
$75.59
$1,168.62
Feeder
$25.63
$55.36
$1,223.98
Power Supply
$50.00
$54.00
$1,277.98
Stepper Motor - 29 oz.in (200 steps/rev, Threaded Shaft)
$29.95
$32.35
$1,310.32
misc hardware
$50.00
$54.00
$1,364.32
Vacuum pump
$30.00
$32.40
$1,396.72
Raw Material
$100.00
$108.00
$1,504.72
Acrylic Base
$40.00
$43.20
$1,547.92
Micro Switches
$15.00
$16.20
$1,564.12
Figure 7 – Project Cost Analysis
Cost analysis
Mechanical frame
16.2
6.2
Micro controller
8.6
Motors
69
Others hardware
components
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Figure 8 – Promotional Flyer
Page | 13