Goals of the project
The intent of the project was to create a radio telescope capable of mapping hydrogen in the galaxy and teaching young, aspiring astronomers how different (non-optical) types of telescopes are constructed. We additionally sought to reach the greatest number of students by traveling to local high schools and inspire them by demonstrating the sort of projects that students (not too different from themselves) are able to accomplish.
Nature of the Collaboration
This project was very collaborative from the beginning. While it started as a dream shared by just 2 students, it rapidly expanded to include 14 other members all with passions for building and physics. Along the way, we’ve collaborated with many members of the Yale faculty and as shared our passions with High school students.
Skills
The skills that encompassed this project included computer aided design (CAD) and mechanical design, computer programming in Python, basic electronics and circuitry, basic workshop skills, and machining skills.
The team members who worked on the physical structure of the radio telescope planned out the dimensions of steel that they would need to build the triangular base and mast. They then had to machine the parts using a milling machine, bandsaw, and drill press. The mast collars were designed in Inventor Fusion (AutoDesk), and the parts were machined using a milling machine, sander, and lathe. After, the collar components were welded together. With all of the parts of the base complete, the triangular base was also welded together, leaving the mast and upper legs of the design detachable for transportation. The dish came in a kit, and team members had to cut a roll of mesh into triangles that would be rivited to the frame.
On the electronics side, team members explored different data reduction programs that could be used alongside the radio telescope. One option was using MIT Haystack Observatory’s java program that automatically does the data reduction and rotor controls. The other option that was explored was GNU Radio open source software, RTL-Power. RTL-Power is a general purpose FFT integrator that uses Python. This option allowed us to customize the algorithms and data that we wanted to take and reduce. The electronics team learned how to send radio signals to a computer by using software-defined radio. The combination of RTL-Power and the software-defined radio dongle is the way that we plan to do research with the radio telescope.
The robotics team had to set up and figure out how to control the rotor system. This required soldering and rewiring the wires to the rotator for ease of setup and safety, and also writing Python code that would send an instruction command line to the controller box. By using our own code, this will allow us to run the movement and data collection code in parallel.
Tools
3D Printer – We used this to print out gears for the small prototype of our telescope.
CAD – We used SolidWorks and Auto Cad to design the parts before they were built.
Laser Cutter – We also used this to cut out a larger gear for the small prototype.
General Machinery Tools – These tools, including drills, saws, hammers, screwdrivers, and rivet guns, were a very important part of our project. We used them at every meeting as we were building and assembling the dish and base.
Heavy Machinery – We used a shop that had a band saw, drill press, welder, and sanding belt to build the base of the telescope.
Python – Python was used to write a program that allows our telescope to track satellites.
Arduino – Arduino was used to run the motor that moved the prototype telescope.
CorelDraw – We used CorelDraw to design several components of the prototype telescope including one of the gears.
Process
The original project was inspired by the MIT-Cassi Corp. telescope, but quickly changed to more reflect the group’s creative energy. The base of the dish was changed so that it was sturdier and was able to resist the wind more effectively. We took advantage of newer technologies such as software defined radio processing and added extra functionality to the control software.
Milestones
The first semester of this project was devoted to the construction of a prototype telescope using a satellite dish and wooden gear system mobilized with two stepper motors. The prototype project introduced members to many of the concepts of signal processing, mount construction, and motorization on a smaller scale.
In second semester, two notable milestones occurred with the successful implementation of the motor system (mid February) and the finalized construction of the mount (late March). The motor system was purchased from RFHamdesign, so much of the work involved the construction of software to interface with the RF system, culminating with successfully controlled rotation. The mount was designed in SolidWorks over the course of January and early February; actual construction occurred during February and March. The two systems were successfully combined in late March, representing the completion of the physical aspect of the project.
Currently, work continues on the remaining area of operation – electronic signal processing. We intend to finish this by mid-April, after which we will be able to successfully take measurements.
Challenges encountered
We learned a lot about effective team management, CAD, prototyping, and manufacturing. Our biggest obstacles were meeting the design constraints put on the telescope by the administrators at the Leitner Observatory (the telescope’s final location), and the logistics of transporting the dish from Yale to the various high schools in the New Haven area.
Major outcomes
From a physical standpoint, the project yielded a fully-functioning radio telescope that can be used to track celestial objects while observing HI 21 cm emission. Additionally, the team has produced an impressive body of code to perform the various necessary tasks, such as pointing the telescope, tracking targets, collecting data, and reducing data. However, the more impactful outcomes of the project have certainly been the experiences of the team members. Team members came from a wide range of backgrounds, and the inter-disciplinary nature of the project benefited each of them uniquely. Members have gained experience in engineering, programming, astronomical instrumentation, and astronomical theory. However, most importantly, the project fostered skills in cross-disciplinary communication and cooperation.
Innovations, impact and successes
On a practical level, this project’s major innovations will involve the construction of a simplified, elegant mount design as well as well a streamlined, easy to use set of programs for synthesized rotation and signal processing. In particular, we intend to use the telescope to observe bodies in the solar system, produce Galactic Rotation Curve of the Milky Way, and track a number of L-Band satellites. We also hope to produce clear, complete documentation for all aspects of the project (especially software) which will be useful to future groups involved in Radio Astronomy.
In terms of outreach, we intend to bring the telescope to a number of New Haven high schools, accompanied by a presentation focused both on the underlying scientific principles involved in its construction and the mindset required to accomplish complex engineering tasks.
Most importantly, however, the project has allowed the group members themselves to meaningfully engage with the engineering involved in scientific observation. In particular, the team has had to synthesize skills and knowledge from a wide variety of engineering/construction disciplines (structural/electrical/mechanical engineering, computer science) with an understanding of the physics involved in the pursuit of our objectives. Such multifaceted thinking is at the heart of good science and good engineering, and it is without doubt the most valuable result of this project.
Devin Cody
