A Project-based First Year Electrical and Computer Engineering Course: Sensor and Telemetry Systems for High-altitude Balloons

摘要

This paper documents an innovative, project-based 1~(st)-year course in electrical and computer engineering recently developed and implemented at DigiPen Institute of Technology. The primary objective of the course is to engage students in authentic engineering work early in their academic careers. Previous studies have shown that student engagement often leads to increased student retention rates in engineering programs. Moreover, including engineering work in the 1st year of a program often better prepares students for their subsequent and more advanced engineering courses. The project currently implemented consists of sensor and telemetry systems for high-altitude balloons. Students are required to use the cricketsat design approach, which involves an electric circuit with an output that changes frequency based on properties of the atmosphere. The output of this sensor circuit is then used to amplitude modulate a 433 MHz carrier frequency for longdistance RF communication. The first milestone of the project is to build and test a 555-timer-based cricketsat that measures temperature with a thermistor following a prescribed design. Subsequently, the 555-timer is replaced by a PIC microcontroller (MCU) in the temperature sensing circuit. For the remainder of the project, students work in teams to design their own MCU-based sensor system to measure any property of the atmosphere that changes with altitude, excluding temperature (EM radiation, humidity, wind, pressures, etc.), or instead, they can test an engineering design in the upper atmosphere. Students must make a proposal of their planned project to faculty and peers through an oral presentation and written documents. Once the design is approved, students are required to prototype their design on a breadboard. After testing the prototype, students design, populate, and test a printed circuit board. All of this work culminates with student sensors systems being launched on large weather balloons to about 30 km altitude. In the last few weeks of class, students analyze their data, present their work orally, and write final reports.