Linux at the University

In outer space, on the ground, and in the classroom: some exciting real-world applications developed with Linux by students and researchers at the University of Colorado in Boulder.
Linux in the Classroom

As the economy of the United States transitions from the Industrial Age to the Information Age, students from all engineering disciplines are required to enable the automation and control of large and small industrial production processes. The per dollar cost of storage media, CPU cycles and interface hardware continues to decline, allowing research agencies and for-profit companies to implement automation of their production processes in an effort to decrease costs and increase profit margin. At the College of Engineering and Sciences, located on the main campus of the University of Colorado, a new teaching paradigm has been realized with the completion of the Integrated Teaching and Learning Laboratory (ITLL). The ITLL was built as a resource for students of all engineering disciplines to facilitate the transfer of theory learned in the classroom to actual practice in the laboratory, in an effort to teach real world engineering and scientific skills.

The ITLL provides the resources to allow students to design and build complex engineering projects. A typical lab station is shown in Figure 15. Each of the lab stations is equipped with a Hewlett-Packard Vectra PC with a 500MHz Pentium-III processor, 384MB of RAM, an 8GB hard drive, the usual NIC and a National Instruments analog and digital data acquisition card. Several of the 80 available systems have been configured to boot Linux and RTLinux, in addition to Windows NT. Standard test equipment at each lab station includes a waveform generator, digital multi-meter, variable-voltage power supply and oscilloscope. The breakout panel provides easy access to analog and digital IO signals and to signal-conditioning hardware. The availability of sophisticated test equipment, coupled with the capabilities of the Linux and RTLinux operating systems, has enabled students to design and construct complex, real world applications integrating both hardware and software to accomplish a specified engineering or scientific task.

Figure 15. An ITLL Workstation Running Linux/RTLinux.

One such project is the University of Colorado's Robotic Autonomous Transport, a.k.a. the RATmobile, shown in Figure 16. The RATmobile is an unmanned ground vehicle (UGV) that navigates autonomously by sensing static and dynamic features within its environment. This vehicle was designed entirely from scratch by a group of undergraduate and graduate students from several engineering disciplines with supervision and guidance from members of the Aerospace department. Design and construction of the vehicle is truly multi-disciplinary, calling upon the theory and expertise of mechanical, electrical, aerospace and computer sciences.

The vehicle uses miniature video cameras mounted on the front to supply visual information concerning the surrounding environment. Static and dynamic obstacle detection is supplemented by an array of ultrasonic sensors. The sensed environmental conditions are combined into a local coordinate frame and then translated into a world representation map that contains the totality of the robot's knowledge concerning its environment. Depending upon the task at hand, the robot is able to make use of different navigational algorithms to traverse to a desired destination.

One such navigational mode allows for the vehicle to navigate an obstacle course that is delimited by painted white lines on a large field. The lines are approximately ten feet apart with straightaways, sharp curves and bends and even some occurrences of missing lines, which require that the navigation algorithm predict the desired vehicle direction based upon historical information. A second navigational mode makes use of differential GPS information for precise assessment of the robot's position in a world reference frame. In this mode, the vehicle has a priori knowledge of its static environment and can navigate to a predetermined location while avoiding unmapped or dynamic obstacles. Different navigational strategies, such as the optimization of path length or required path energy, are easily implemented.

Linux was chosen as the operating system for this project because it met all design requirements, allowed for a multi- user development environment and was free, which is of concern to students with a limited project budget. The capability of the multi-threaded software control architecture provided by Linux allows for easy implementation of differing vehicle capabilities. The primary functions of the vehicle, visual image acquisition; obstacle detection information acquisition; combination of input sensory data into a world representation; and the determination of the required navigational control outputs of velocity and steer angle, are all abstracted to different threads. If necessary, the CPU scheduling policy associated with different processes can be altered from the default scheduler, which optimizes for the average case, to allow for improved real-time performance under the standard Linux OS. In process control systems, where millisecond and below guaranteed scheduling is required, a real-time Linux variant, such as RTLinux, can be used.

Figure 16. The Robotic Autonomous Transport (RATmobile)

The ITLL stations, running either Linux or RTLinux, are also used in a class emphasizing hardware/software integration skills to undergraduate and graduate students. Advanced programming constructs, in the C and C++ languages, are required by laboratory exercises that emphasize the integration of real hardware, such as motors and micro-controllers. This allows students to develop confidence and expertise not just in proper software programming practices, but in combining control hardware with the standard PC. Examples of final student projects (all using Linux or RTLinux) in this class include:

  • A working mockup of a spin stabilized satellite that uses image processing to determine orientation within a star field.

  • A directionally controlled scanning laser used to determine mechanical vibrational modes within a structure.

  • Transmission of real-time accelerometer data from a radio controlled airplane with subsequent real-time plotting capability.

  • The construction of a fluid chamber to model fluid flow through different chambers of the heart with associated real-time data gathering for analysis.

Using the Linux OS and user-configurable development environments as a basis, we are able to impart a greater breadth of knowledge to our students, which is applicable to real world engineering problems. That is a true accomplishment whose accolades belong to the numerous kernel and development programmers whom have contributed to the power and success of Linux.

Linux also serves as a powerful teaching tool within our Computer Science department. The free availability of the Linux OS and associated development packages have opened the doors to a greater variety of course content in classes pertaining to Systems Administration. With a free operating system and the availability of cheap PC hardware, students have the ability to configure and administer all aspects of their very own system within a university computer lab. If something goes dramatically wrong, it is a simple matter to restore the entire disk across a network from a master system. This encourages students to experiment with no disastrous repercussions. Topics such as disk-level file recovery, device installation and management, user and file administration, kernel configuration and networking are all candidates for easily constructed exercises using the free Linux OS as the enabling technology.

Open source distribution of the Linux kernel source tree has allowed courses in Operating Systems Theory to not only teach the fundamentals but, even more importantly, allow the students to experiment with changes to the kernel code. As a result, students are offered a richer set of exercises that can be applied directly to the kernel source and not just on paper. Most assuredly, students will break their systems while experimenting, but system recovery strategies have definite educational value—better now on a cheap PC running Linux than on some multi-million dollar platform in the future. Having the kernel source allows for in-depth exercises in far-ranging topics including management of processes, resources, devices, files and memory, as well as implementation of kernel-space processes as Linux modules, scheduling policies and priorities, and fundamental synchronization methodologies. Linux enables a richer and more realistic educational experience for our students.

______________________

Comments

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Engineering and Programming

Student Administration Systems Guy's picture

This is a great article to show students how close the ties are between computer programming and computer engineering. At my University those two fields are split into two different degrees, with little overlap in course work. I think they should be closer brothers.

White Paper
Linux Management with Red Hat Satellite: Measuring Business Impact and ROI

Linux has become a key foundation for supporting today's rapidly growing IT environments. Linux is being used to deploy business applications and databases, trading on its reputation as a low-cost operating environment. For many IT organizations, Linux is a mainstay for deploying Web servers and has evolved from handling basic file, print, and utility workloads to running mission-critical applications and databases, physically, virtually, and in the cloud. As Linux grows in importance in terms of value to the business, managing Linux environments to high standards of service quality — availability, security, and performance — becomes an essential requirement for business success.

Learn More

Sponsored by Red Hat

White Paper
Private PaaS for the Agile Enterprise

If you already use virtualized infrastructure, you are well on your way to leveraging the power of the cloud. Virtualization offers the promise of limitless resources, but how do you manage that scalability when your DevOps team doesn’t scale? In today’s hypercompetitive markets, fast results can make a difference between leading the pack vs. obsolescence. Organizations need more benefits from cloud computing than just raw resources. They need agility, flexibility, convenience, ROI, and control.

Stackato private Platform-as-a-Service technology from ActiveState extends your private cloud infrastructure by creating a private PaaS to provide on-demand availability, flexibility, control, and ultimately, faster time-to-market for your enterprise.

Learn More

Sponsored by ActiveState