College of Engineering Rachel Berlin-Allaire, Ashley Raby, Rafael Schaffa & Lisa Thomas

INVERTED PENDULUM Technology and Innovation

•  Develop a mechanical system with the capabilities of stabilizing an inverted pendulum that is mounted to a cart and actuated along a linear rail by a timing belt

•  Develop a controls algorithm to stabilize the pendulum around its unstable equilibrium point

•  Control the horizontal position of the cart

Design Concept

University and Industry Engagement

Mechanical Engineering Department •  Nabil Chalhoub •  Golam Newaz •  Anthony Composto •  Gurpinder Singh •  Kayla Marshall •  Brian Thompson •  Lisa Rapicano Physics Machine Shop Team •  Marvin Santure •  Bob Kas-Mikha Corporate Supporters •  Mahle •  Comau

Community Impact & Value

•  To be implemented in Wayne State University’s mechanical engineering undergraduate research lab.

•  Learning mechanism for future WSU control’s students

•  Physical application of controls applied to a non-linear system often found in texts and research literature

Future Work

•  Implement a swing-up routine and then switch to controller for stabilizing pendulum

•  Implement switches to cut power to the system when cart is out of range

•  Fine tune PID controller to diminish overshoot and have more efficient stabilization

Controls Concept

Mechanical Design Considerations

•  Robust – to be used in subsequent semesters •  Keep system safe from damaging itself

- Install rubber stops on either end of both rails - Install two switches to cut power to the

system when cart moves out of range •  Use of two encoders with 4096 pulses/

revolution to ensure accurate detection of pendulum angle, and linear position of cart

•  Belt driven Controls Considerations

•  Create plant using SimMechanics to represent physical system and create simulation

•  Use of PID controller to stabilize pendulum and tune system using simulated plant.

•  Create an angular offset to allow for linear movement and control over horizontal placement of pendulum cart

References

•  K. Sultan, “Inverted pendulum, analysis, design and implementation,” IIEE, Inst. of Eng. Pakistan. 2002

•  R. G. Moreno and C. P. Gatico, “FPGA-Based Model of an Inverted Pendulum Hardware-in-the-Loop Simulations,” Univ. of Pad, Germany.