The first phase of my dissertation research is to create a laboratory kit that can be used in the introduction to controls course in General Engineering (GE). I have included a description of the course, the existing equipment, the contents of the kit, and a comparison of the laboratory exercises below.
Control Systems (GE320) is the first course in control systems for students in the General Engineering (GE) program at the University of Illinois at Urbana-Champaign. It covers topics such as Laplace transforms, system identification and stability, continuous-time control algorithms such as proportional-integral-derivative (PID) and lead-lag. The course is required for all GE students and serves as a prerequisite for GE420, a digital controls course that is also required for all GE students. These two courses serve as prerequisites for three of the 19 pre-approved Secondary Field Options that GE students can select to meet the degree requirements. GE320 is typically taken in the junior year. Students must register for lecture and one section of laboratory. The course has approximately three hours of lecture per week. In the fall semester of 2014, the lecture will be twice per week for 80 minutes and limited to 70 students. There are six weeks assigned to complete cookbook laboratory experiments. These experiments cover topics such as introduction to equipment, sensor calibration, system identification and control development. There are a maximum of 10 students per laboratory section.
The current cost of laboratory equipment used in the GE320 lab at UIUC is included in Table 1 below and a photo of a bench in the current UIUC Controls Laboratory is in Figure 1.
|HP 33120A Function Generator (Discontinued, replaced by Agilent 33220A)||$ 2,487.00|
|HP 34401A Multimeter||$ 1,159.00|
|HP 6632A DC Power Supply (Discontinued, replaced with Agilent E3648A)||$ 1,320.00|
|Custom-built patch panel, power supplies, and amplifer||$ 475.00|
|Comdyna GP-6 Analog Computer (No longer produced)||$ 1,500.00|
|DC motor, enclosure, and sensors||$ 450.00|
|Dell Precision T3400 PC||$ 1,094.00|
|Agilent Technologies DSO6012A Oscilloscope||$ 6,159.00|
|Miscellaneous wires||$ 195.31|
New Laboratory Kit
The kit that will be used for this project in GE320 laboratory was created for approximately $140, barely exceeding the goal of $100. The breakdown of the equipment and cost are in Table 2. Figure 2 shows a protoype of the current kit. The information in Table 3 summarizes the GE320 experiments with the old equipment and how they are replicated with the new equipment. In this study, the kits will be provided for the students to use in the existing laboratory space.
|Raspberry Pi||$ 39.95|
|12V DC motor||$ 12.95|
|Motor enclosure and hub||$ 5.94|
|3-D printed stand for motor and sensors||$ 5.00|
|H bridge (L293D)||$ 4.12|
|Analog-to-digital converter (MCP3008)||$ 2.63|
|Power supplies||$ 13.85|
|Pi cobbler breakout and cable||$ 7.95|
|SD card||$ 7.95|
Within the current equipment in the GE320 kit, motor identification in experiment 2 could not be replicated. For this experiment, both voltage and current will need to be varied. Additionally, the frequency response part of experiment 3 could not be replicated. It can be added with another power supply and digital to analog conversion integrated circuit for about $17. Since the students will be using the kit in the same room as the traditional equipment, the required power supply and function generator will be available for use in these experiments. The last lab will be the same for both types of equipment.
|1||Introduction to GP-6 Analog Computer||Introduction to Simulink and Raspberry Pi Interface|
|2||Motor and sensor characteristics||Motor and sensor characteristics|
|3||Motor identification via physical and electrical characteristics||Functionality not available within the cost of the kit|
|4||Motor identification via step and frequency response||Motor identification via step|
|5||Motor control (Proportional, Proportional + Derivative, & Proportional + Speed)||Motor control (Proportional, Proportional + Derivative, & Proportional + Speed)|
|6||System ID and Control of a non-linear system via the web||System ID and Control of a non-linear system via the web|