PNEUMATIC INVERTED PENDULUM
Keywords:Pneumatic,inverted pendulum,automatic controls,pid,lqr.
Motivation and Audience: This tutorial's motivation is to study about the mechanisms behind the control of an inverted pendulum , which is largely used in the robotics industry. Readers of this tutorial assumes the reader has the following background and interests:
Overview:This tutorial is an adaptation from Jiyue Hue tutorial , which is available here: Jiyue He from DASL-Drexel
The rest of the tutorial is presented as follows:
Parts List and Source
How it works
Using a linear encoder and a rotational encoder, we can calculate the cart position and the pendulum angle. The cart velocity and the pendulum angular velocity can be calculated through programming.
The PD loop will calculate the necessary input voltage to be sent to the proportional valve. As the proportional valve only takes analog signals, we will need to convert the digital input calculated by the Arduino code to an analog signal – a DAC (digital to analog converter) and an operational amplifier can be used. The DAC’s output (current) is very little, so the use of an operational amplifier to amplify this signal is necessary (the signal that goes to the proportional valve is voltage). The digital value calculated by the Arduino will be send to the DAC, which will give a current output, that goes to the operational amplifier and then the output voltage goes to the proportional valve. The proportional valve takes the input voltage and gives a force output, which will drive the cart forward or backward depending on the pendulum angle.
Original project working: http://dasl.mem.drexel.edu/~jiyueHe/pneumatic_inverted_pendulum/index.html
As the original tutorial related , the system's performance is not very good. Can be pointed: