By: Andrew Hovingh & Matt Roon Project # ME Faculty and Industrial Mentor: Dr. James Kamman Industrial Sponsor: Parker Hannifin Corporation

Agenda  Introduction  Analysis  Physical System Design  Control Implementation  Physical Results  Limitations  Recommendations  Acknowledgments  Questions

Introduction  Parker Hannifin Motion and Control Laboratory  Established to enhance students’ knowledge of hydraulics, pneumatics, and electromechanical engineering

Background  “Balancing a Broomstick” and Control Theory

Background  Stability and the Inverted Pendulum Normal Pendulum (Stable) (Easy to Control θ) Inverted Pendulum (Unstable) (Difficult to Control θ) Classic Problem in Control Labs

Background  Why is control important?

Project Objectives  Design and simulate control logic and system response  Design and construct inverted pendulum assembly  Keep the pendulum balancing for approximately a 15 second duration

Analysis  Process begins by describing the physics of the system

Analysis  Control theory was applied to develop a potential type of controller and tune its specific components  Example Types: P, PD, or PID Phase Lead, Phase Lag, or Phase Lead-Lag Others

Analysis  Simulations and software tools were developed in MATLAB and Simulink to predict the response of the system for different parameters

Analysis

Angle Sensor Selection  Manipulating the simulations, it was apparent a high resolution sensor was necessary  Both analog and digital sensors were considered, however a digital sensor was chosen based on its relative insensitivity to electronic interference (noise)  A rotary incremental encoder was the best option for this particular application

Angle Sensor Selection  Turck Digital Encoder  Resolution: counts/revolution  Accurate to 1/100 th of one degree

Physical System Design  Physical system constraints were analyzed and brainstorming sessions were conducted  Design Factors Low Cost Modularity Reliability  Ideas mapped out via Pro-Engineer

Physical System Design  Potential suppliers were sought after and justified based on capabilities to accommodate specific machining requirements  Supplier part consistency, effective communication, and lead time were crucial to ensuring a trouble-free physical system build

Physical System Design

 Stack-ups and GD&T (Geometric Dimensioning and Tolerancing)

Final Physical System

Control Implementation  Control flow chart

Control Implementation  LabVIEW, a graphical software programming package used in data acquisition and control, was used to implement the control logic in the physical system

Control Implementation  Front panel interface with user controls  Provides monitoring of signals  Provides configurable settings for rapid control execution

Physical Results

Limitations  Difficult to define the vertical position of the pendulum, which changes from day to day  Sled position drift limits the duration of angle control  Variation in the real system makes accurate simulation predictions challenging

Recommendations  Longer pendulum  Control sled position and pendulum angle simultaneously  Place strings on ends of stroke to keep the sled in range  Attempt other system configurations Angle velocity and sled velocity feedback Different controller types  Achieve better initial conditions with release mechanism

Acknowledgments  Parker Hannifin Corporation  Dr. James Kamman  Dr. Kapseong Ro  Glenn Hall

Thank You!