Robotic Manufacturing Cell

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Work Cell
Team Name CyberCrew
Sponsors
Team Members
  • Iulian David
  • Mark Leitner
  • Faihan Aldouseri
  • Abdulmuhsen Alhajeri
Duration Summer 2018 - Fall 2018
Faculty Adviser Dr. Steven Beyerlein
Mentor
  • Ankit Gupta
Client
  • Name / Organization

The Integration of two robotic entities into a miniature assembly line, in order to make a product involving operations of barcode scanning, part manipulation, fixture design, and supervisory control.


Problem Definition[edit]

In past projects, teams have not been able to integrate the two robots into one process. Our goal this year is to ensure this happens. A new end effector will be necessarily designed in order to assemble the products. The final process, put simply, will be to sort through various male and female pieces using the scanner. Once the two are separated into their respective destinations, the arm will grab the male piece and place it into the construction zone, then grab the female piece and place it on top of the male one. The other robot will then push the pieces together using the constructed end effector. This way, the two robots will be working together in one manufacturing process.


Background[edit]

2013-2014 In Spring 2013 The Boeing Company donated DENSO robotic arms to The University of Idaho College of Engineering. That fall Mechanical and Electrical Engineering students, as a part of Team Roboshow, were tasked to learn basic programming of the robotic arms and create a work-cell for the arms. Their work-cell incorporated multiple safety features as well as a clear poly-carbonate enclosure for public demonstration. The team was able to successfully program the robot to use a dry-erase marker to create logos and patterns on a white board.

2014-2015 The following year another design team, known as Team Vandalbot, was formed to design a manufacturing process which could assemble various rivet and nut-plate assemblies in order to automate a repetitive task currently done by factory workers. The team was able to demonstrate this process and provide documentation for future teams.

Summer-Fall 2016 During the Summer and Fall of 2016 Do All Robotics completely redesigned the robotic manufacturing cell. They made the cell larger which allowed for operators to have easier access to the robots for things like maintenance or changing end effectors. They also made the work cell fully modular allowing future teams to rearrange the cell for their specific needs. New pedestals for the robots were also designed because the originals were very unsteady. The team also performed stress analysis on the new pedestals to ensure they wouldn't break or fall over during operation. The team also programmed the robots to do tasks such as stack cups and write with a marker on a board. Finally the team also created a simple beginners manual that included all the basics needed to run the robot.

Summer-Fall 2017 The next year, the design team for the Robotic Arm Manufacturing Cell, Team CSRM, integrated a simple vision system involving a scanner, so that the arms could sort through two varied parts. These parts, a rectangle and a hexagon, were created by the team members, as well as the fixtures these parts were based in. Their process involved one of the robotic arms picking up pieces from a randomized mixture, then scanning the object to sort between the two. To pick the objects up, the robot used a pneumatic gripping mechanism.

Client Needs[edit]

Our client is Ankit Gupta, the professor for the industrial automation class. Working on this project could inspire future assignments for the class, as well as requests for perhaps even more progression for students to learn about these robotic arms. This will enable enhancements to improve the class. As the request for this specific project, we are tasked to integrate the two arms into one manufacturing process. Other requirements involve using the scanner to “see” which part is which: male or female. In order to perform this process, unique end effectors and fixtures will need to be designed, which will be available for future class use as well.


Deliverables[edit]

  • Incorporate two robots in one manufacturing process
  • Design and construct male and female parts
  • Design and construct an end effector to assemble the parts
  • Design and construct an incoming queue ramp
  • Design and construct fixtures the assembled part
  • Use the scanner to sort through various pieces
  • Design and Construct Conveyor Belt
  • Integrate all 4 equipment work together

Design Specifications/Constrains[edit]

Device Specification Variable Limit
Robotic Arm Fixture Mass 5 Kg
Robotic Arm Gripper Pressure .39 MPa
Robotic Arm (Nr. 196-549) Arm Maximum Coordinate length 762 mm on X-axis
Ramp Female Slide Angle 40°
Ramp Male Slide Angle 62°
Conveyor Maximum Belt Tension Force 5 lbf for 0.139 hp Motor
Conveyor Kinetic Friction Nylon-Dry Aluminum μ=0.21

Project Learning[edit]

  • Step 1: Load queue (Operator loads assembly parts into the ramp)
  • Step 2: Exit Cell (Operator departs manufacturing cell)
  • Step 3: Start Program (Operator executes code)
  • Step 4: Scan Part (The first part out of the ramp is scanned with bar code scanner)
  • Step 5: Sorting Process (If there are multiple consecutive parts of the same type, R1 will replace them to the top of the ramp)
  • Step 6: Move 1st part to intermediate storage (Robot 1 (R1) will move female to intermediate storage as the base of assembly)
  • Step 7: Move 2nd part to intermediate storage (R1 will move and place a male part right on top of the female)
  • Step 8: Assembly (Robot 2 (R2) will push male part with designed "Finger" end effector, clamping the pieces to create assembly)
  • Step 9: Product Storage (Final assembly will be placed in a box once it is put together)
  • Step 10: Repeat the loop (If the scanner has a bar code in front, the loop will be repeated. If there is no bar code to read, then the task is complete and the robots will return to their initial positions.)
Flow Chart Description
Manufacturing Flow Chart
After the operator manually loads the assembly parts into the ramp and exits the cell, they need to start the program. The first part is scanned at the bottom of the ramp. If the computer recognizes the part as female, Robot 1 will pick it up, placing it into intermediate storage as the base for the assembly. If the next part is male, Robot 1 will pick it up place it in the intermediate storage over the female part as the top of the assembly. However, since the pieces in the queue are randomized, there is potential for consecutive parts of the same type. If this is the case, and the part comes in the wrong order, Robot 1 will pick it up, returning it to the top of the ramp, sorting the pieces over time. Robot 2 will then activate and move to the location of the parts. Its end effector, a finger-like tool, will push the male part into the base, clamping the two parts together using an o-ring. Robot 1 will then pick the whole assembly up and deposit it into the storage. After the assembly is deposited, the next part will be scanned, repeating the loop. If no parts are scanned, the arms return to their initial position.

Design Solution[edit]

Prove of the concept[edit]

Primary Achieved Goal Description Methodology
2018 CyberCrew preliminary process.gif
Initially we had three choices to implement the connection between the two robot arms.
  • MINI I/O Method - as shown in the first segment of the picture, Mini I/O represents a vast number of ports, but only 8 of them have the capacity to connect different devices. The problem consists of a time consuming process of reconnecting devices. Any devices have to be soldered to be connected. Mini I/O, as mentioned before, has a limit of only 8 devices able to connect, meaning that every time one will need to put any other devices, it will require the disconnect and solder the color coded wire back. We decided to figure out other way of sending the signal between robots.
  • Scanner Signal - In the second segment of the picture, the bar code is shown under the robot arm. That is the one way to sent a signal to Robot 2, but in this case both robots serve as clients, and the bar code scanner is the manipulator of them. When Robot 1 is done with its task it goes and scans the bar code which serves as a command for Robot 2 to start its task. The problem with this method is several extra movements which results in increasing the cycle time and increasing the energy consumed. It also requires more feedback to connect other devices.
  • TCP/IP - This method is shown in the third segment of the picture. This is the best method to connect two robots to communicate with each other. The connection between IP's of two robots happens via an Ethernet hub. The best thing about this is it allows one to connect a vast number of devices which support IP protocol. When IP protocols are established it is much easier to connect devices because it eliminates physical wire connections.
2018 CyberCrew Methods.JPG

System Architecture[edit]

Solid Model Description Physical Model
Cell Layout
The room layout has a diagonal equipment arrangement which makes Robot Nr 1 to make 180° rotation. That arrangement gives a good time efficiency

Parts Design[edit]

Male and Female Parts
2018 CyberCrew MalePart.PNG
2018 CyberCrew FemalePart.PNG
Final Design

The manufacturing cell will operate with two unique types of parts: Male and Female. During the process, Male parts will serve as a bottom base of the whole assembly and the Female part will be inserted into the top of the male part, creating the final assembled product. There will be 3 assembly with free different colors: Gold, Silver, Black.

The Male part has:

  • Design Software: 3D SolidWorks
    • 2" height
    • 2" outer diameter
    • 1"-0.001 inner diameter of rod (slip fit)
    • 1" rod height

The Female part has:

  • Design Software: 3D SolidWorks
    • 1" height
    • 2" outer diameter
    • 1" inner diameter (slip fit)
    • hollowed through
  • Manufactured: Sindoh 3D Printer
  • Material: 100% PLA (plastic)


Male Part has a channel for the o-ring which serves the function of clamping the two parts together.

Ramp Design[edit]

Solid Model Description Physical Model
3D Ramp Assembly
The Ramp is designed to Sort the Male and Female parts. In the Robotic Manufacturing Cell the Ramp is the first station to deliver the parts. The top base of the ramp is designed under the 20° slope for X-direction and 45° of slope for Z-direction, that way all female parts slides to the left side and all male pats slide to the right side because of the angled plate attached right above female side, which limit the access to left for male parts and guide them straight to left side. In the Physical picture can be observed that each end of the slide has the special end fixture designed exactly for the parts, and they are removable. The slope of each slide is different because of the different centroid of the each part, which is calibrated to slide not very fast and not very slow, and to dump over the end fixtures of the ramp.
Physical Ramp Assembly

End Effector (Push Finger)[edit]

Solid Model Description Physical Model
3D End Effector (Push Finger) full assembly
3D End Effector (Push Finger) Exploded View
End effector (push finger) designed for Robot Arm 2, whose function is to push the assembly together until it clamps.

The total length of the end effector is 7.5 inches and it is composed of:

  • Plastic End (it is made 100% PLA (plastic) manufactured on a 3D printer to not impact the parts as the robot pushes the pieces together)
  • Front Washer (it is made of steel and serves as a stop for spring at both ends)
  • Hollow Cylinder (it is made of aluminum 6061 alloy, and it serves as a base trajectory for spring)
  • Cylinder Base/Cylinder Holder (it is made 100% PLA (plastic) manufactured on a 3D printer. Serves as a holder for the aluminum cylinder which drives straight through the holder and supports forces from the spring through washer.)
  • Back Washer (made of brass and manufactured using a CNC lathe and manual mill machine. The main function is to stop the spring from expanding. It also serves as a way to adjust end effector stiffness.)
  • Adapter (made of 100% PLA (plastic) and manufactured on a 3D printer. The main function is to connect the end effector to Robot Arm 2.)
Physical Push Finger Assembly

Gripper[edit]

Solid Model Description Physical Model
3D Gripper full assembly
3D Gripper Exploded View
The end effector (gripper) is used by Robot Arm 1 to grab the parts of the future assembly and put them in the place where they will be clamped together and again moved as an assembly unit to the storage.

The material used for building this end effector is 100% PLA (plastic) for Lips, manufactured in a 3D printer and fingers are made from aluminum manufactured on CNC Mill Machine. The lips was made 100% from PLA material because it was necessary to maintain the flexibility to change the lips conform different shape of the assembly parts, and 3D printer makes manufacturing process very easy and fast. The parts have a 2 inch diameter, which was why we maintained the 2 inch diameter between the claws. To make sure the moving part is fixed in the gripper, and will not be deformed by the gripper's pressure, designer implemented channels in the claws serve as spaces for glued o-rings. The part will be fixed uniformly and because the o-rings are made from rubber and have more flexibility, it will maintain the part's shape.

Physical Gripper Assembly

Fixtures[edit]

Solid Model Description
Storage

The figure represents the assembly storage. Robot 1 will grab the parts and place it in a assembly storage spot designated conform bar code color of the part. In this station for assembly process are involved function of both robot arms. The batch of assembly storage consists of 3 full assemblies, as shown in the figure. The material is wood, manufacturing process was done in a laser cutter and hole dimensions are shown in a figure next to.


Belt Conveyor[edit]

Solid Model Description Physical Model
3D Belt Conveyor Assembly
For delivering the finished parts to the final destination, we built the automatic conveyor belt. The conveyor belt frame is built from 8020 aluminum profiles of 6061 series alloy. The top of the belt is made from rubber material and the bottom (drive side of the belt) is made from unknown material close to the Nylon, and Friction coefficient obtained experimentally between two surfaces (Dry aluminum and Unknown Material) is 0.21, which is close to Nylon material.

The frame of the Conveyor consist from two parts, part one is the Base Frame which presents the longest base side of the frame, and second part of the frame is adjustable part, designed specially for the tightening the belt. The belt also has a tightening mechanism which shown in a pictures, and it presents the 6" long bolt screwed into a tightening mechanism base attached to the base frame. The 6" tightening rods has a cap at the end which serves as a concentric part for the contact point between adjustable part of the frame. On top of each side of the frame is located the ruler scale, which defines the tightening force in pounds per each unit of the ruler scale defined experimentally and described in a technical documentations.

Physical Belt Conveyor Assembly
Belt Conveyor Control Equipment
Equipment Description
Stepper Motor
The Conveyor Belt is driven by Stepper Motor Nema23 series which has the maximum torque of 1.8 Nm at 60 RPM or less and the power supply of 24VDC. The transmission to the shaft is provided by two timing pulleys and timing belt of T159 series. The gear ratio is 2 to 1.
Stepper Driver
The Stepper Motor is driven by stepper driver, and as it shown in a picture it can control the Torque and RPM by changing the Pulse rate. The highest Torque will be at 4.20A from current Table.
Arduino Ethernet
To integrate the Conveyor Belt in the robotic automatic system we use the Arduino board with Ethernet IP function, to be able to connect the conveyor through the IP Address through already installed Ethernet hub.
Circuit Diagram
Physical Circuit
Wiring Diagram

SubProblems[edit]

Validation[edit]

Team Members[edit]

Team "CyberCrew"
Member Biography Discipline
Iulian David
2018 CyberCrew Iulian.jpg
I am originally from Moldova, which is a small country in Eastern Europe. I always liked to disassemble different mechanisms and take a look at what was inside and how it worked, that is why I decided to pursue mechanical engineering. In Moldova I finished 3 years of the Mechanical Engineering program in Technical University of Moldova, then I decided to move to the USA. After a couple years living in the USA, I transferred all my credits to University of Idaho to continue my studying in the same program. Now I am a Senior in Mechanical Engineering program at University of Idaho and I am going to graduate in December 2018. My goal is to obtain the maximum experience and knowledge to be able to invent something new, which will make life easier. Mechanical Engineering
Mark Leitner
2018 CyberCrew Mark.jpg
Coming from Richland, Washington, I grew up in the Hanford area. It seemed everyone who lived around me was an engineer. However, it took me a while to realize that I actually wanted to pursue this. After switching majors a couple times, I realized that I missed math, so I switched into the major my sophomore year. Some eventual goals of mine are to live somewhere warm, travel, and have a job that can support my terrible spending habits. Mechanical Engineering
Faihan Aldouseri
2018 CyberCrew Faihan.jpg
I am from Kuwait, which is located in the Middle East. I was born and grew up in Al Ahmadi which has two sides: civilian and industrial. In addition, I graduated from high school and started studying in the famous college of Kuwait starting in 2006. After several years through working as a diesel mechanic and industrial inspector, I realized that I have to complete my studies to improve my knowledge and lifestyle. l like mechanical engineering because I always helped my father to do mechanic stuff on our farm. Mechanical Engineering
Abdulmuhsen Alhajeri
2018 CyberCrew Abdul.jpg
I am from Kuwait. It is a small country but there are lots of companies due to the oil we have back home. So, engineering is an important major to learn and bring back home due to the many companies. I chose Mechanical engineering for two reasons. First, because I like working with machines. Second, because this major has a good future. I hope to gain experience as quickly as I can. Mechanical Engineering

Additional Documentation[edit]

Presentations

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