Update 2/26/17 – Putting things together


Ground ops was hard at work this weekend doing some replacements on the Mk-1 test stand and organizing parts for the Mk-2 test stand. With the momentum gained this weekend, we hope to get most of the plumbing for the Mk-2 stand done over the course of the week.

Mk-2 guts.jpg

Test stand guts waiting to be assembled

We’re currently working towards doing a firing of our engine as a tutorial for new members, planned for the week after spring break, so stay tuned!

Subteam Spotlight: Avionics

We’re back from winter and are a month into our Spring semester now! As we left off last time with our plan to make a consolidated sensors platform, we have come back this semester and have finished a prototype of all our sensors on the board as shown in figure1. The circuit includes 3 thermocouple, 1 pressure sensor, 2 position sensors, 1 accelerometer and 1 load cell. Alex Brenner from our subteam also designed a circuit board for this setup to be a board that would stack above an Arduino Mega. This is something that we will be using as a display piece for a CSE Expo where we will be showing high schoolers how computers for rocket engines are designed.


Figure 1. Sensors Prototype

Also, as far as automating our test stand, we have successfully been able to implement relays driven by microcontroller controlled Power MOSFETS to control the valves. The controller is shown in figure 2 and the relay setup is shown in figure 3. The controller setup was designed such that when a given position is set by the dials, the valves would be opened to the set angle. This will help us throttle the engine at a future date.


Figure 2. Controller Setup for Automation


Figure 3. Relay Setup

Nick Knudsen, who’s working on automation is currently designing a printed circuit board to make this setup more robust and durable so it is test compatible. We hope to test this setup in one of our future tests, the nearest planned test date being in late March. Check back in later to see our progress on the circuit boards and how we would have built a consolidated setup.

Member Spotlight: Dexter Groath

My name is Dexter Groath. I am a Junior of Aerospace Engineering  and Mechanics at the University of Minnesota. I have always been fascinated with rocketry and overcoming all the obstacles to get to space, the final frontier. LPRD Rocketry allows me to build, design, and launch rockets.  Working with he Flight Team lets me know details and nuances that are often not thought of and gives knowledge that can’t be taught in a classroom.

I am an upcoming intern for Orbital ATK and look forward to a future in aerospace and launching lockets.

Dexter Groath.JPG

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!


2/19/17 – Students become Teachers

This week, LPRD gave a presentation about liquid rocket engines to our local Tripoli charter, a hobby rocketry group which helps us launch our solid fuel rockets (and hopefully one day our liquids). The presentation went very well, with a lot of people excited to learn about how liquid engines work. There is a video of the presentation here. If you’re interested in learning about the technical details of our engine and testing procedures all in one sitting, I highly encourage you to check it out!

This week for our spotlights, we have Ground Ops reporting on their valve characterization test from last week, and Engine Team with a Member spotlight from Jonathan, our new Engine Subteam lead this semseter.

Subteam Spotlight: Ground Ops

Ground Ops is currently in learning mode. One of our projects that we are currently working on is the building of the mount for the MK2 engine. The mount not only needs to be built specifically for the MK2 engine, but also for compatibility with the MK2 test stand. This leads me to another project, which is to create a piping system for the MK2 test stand. We have all the materials we need and with some time and research, we hope to have the setup for the MK2 test stand be done by the end of the semester. Along with setting up the MK2 test stand, we are also continuing to run tests on the MK1 test stand to increase familiarity and confidence to prep our team, Ground Ops, for future engine firing. In the meantime, solidifying Ground Ops a team is the ultimate goal and more updates are to come!


Member Spotlight: Johnathan Liberman

I’m Jonathan Liberman, lead for the Engine Subteam, and a second year student in Aerospace Engineering.  LPRD has given me an excellent chance to delve further into rocketry than I have before.  The opportunities to work on liquid fuel engines is a unique one that has provided lots of practical experience and learning.  After I graduate, I would like to continue this and work on rocket engines for actual launch platforms.  My ideal job would be working at SpaceX or Aerojet Rocketdyne developing new engines for the next generation of launch vehicles.

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 2/12/17 – Under Pressure


This week, Jame did his first test as Ground Ops director with the goal of finding the pressure drops across the valves on the test stand, in preparation for a future test. Next week we’ll get a full review of the test, but for now here’s a cool video!

Now let’s get on to the Subteam Spotlight from Flight Team, and Member Spotlight from avionics member Nick Knudsen

Subteam Spotlight: Flight

Flight team has been quite buy, especially since our catastrophic failure from the end of last semester. We are currently working on building our roll control avionics bay, which is designed to stabilize the spin of our rocket in-flight. The expected launch date is near the end of March, so expect a cool update on that!

Other than that, we are also working on redesigning our Cerberus I Rocket to re-launch as the Cerberus II. Since our main issue has been lighting two motors at once for this rocket, we are designing an on-board ignition system, triggered by an acceleration for backup.


We hope to be launching this design in April or May. More updates to come on these, so stay tuned!

Member Spotlight: Nick Knudsen

My name is Nick Knudsen and I am a Freshman majoring in Computer Engineering at the University of Minnesota. I joined LPRD Rocketry because I have been fascinated by rocketry for as long as I can remember. I also wanted to gain some experience building and implementing electrical and software systems. Outside of LPRD I enjoy skiing, playing guitar, reading, and listening to music. In the future, I hope to pursue a career working in the aerospace industry designing and building electrical and avionics systems for aircraft and spacecraft.



Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 2/5/17 – Spring is Here


The new year is back in full swing, and LPRD is gearing up for an eventful spring semester. We have tests to do, rockets to build, engines to design, and much more!

This week, we have the Subteam Spotlight from the Engine subteam, and a member spotlight from our new Ground Ops director, Jame!

Subteam Spotlight: Engine

Engine team has started off this semester strong.  We have several projects lined up for this semester, and we have made good progress on many of them.  Our nitrous engine is nearly ready for testing, and we hope to fire it at Orbital ATK as soon as possible.  Calculations for film cooling, which is critical for running the flight engine, are almost done, and we hope to prepare a test bed for the system in the coming weeks.  Pending completion of the Mk 2 test stand, progress is on track as well to have the first Mk 2 firing before the end of the semester.  We have busy semester ahead of us, and we look forward to seeing the progress we make!

Member Spotlight: Jame Moua

My name is Jame Moua and I am a junior at the University of Minnesota – Twin Cities double majoring in Aerospace Engineering & Mathematics and a minor in Astrophysics. I have been with LPRD Rocketry for a little under a year now. My current role in LPRD Rocketry is that I am the new sub-team lead for Ground Ops. What my current visions for Ground Ops are to familiarize myself with leading tests on the MK1 test stand, the tests being pressurization test and flow rate test, and to setup the MK2 test stand for testing on the newly made MK2 engine. Away from LPRD, I like to talk to friends and family, and participate in events. In addition, some of my favorite hobbies are to game, play sports, get fit, and eat food. For my hopes and dream, I hope to be accepted into the aerospace industry and ultimately become an american astronaut.


Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 12/11/16 – Moving Forward


As finals draw ever closer, LPRD takes a bit of a break to allow our membership more time to study. However, one major test still happened yesterday up in North Branch MN. We finally got the opportunity to launch our Asymmetric Thrust Rocket, the Cerberus, which we had been working on for the past semester. To put it lightly, things did not go as planned. The main motor of the rocket had a pressure failure and the bottom half of the rocket went up in flames. We’ll have a full report on the incident in early 2017, but until then we’ll have to make some decisions about our next design and how to get our liquid engine off the ground.

LPRD as a group is gaining quite a lot of steam. This semester, we have solidified our ignition methods, made progress on a new test stand, and have begun some work on designing our liquid rocket. It’s still in the early stages, but our long term goals put us at launching a liquid rocket in a year or two. Next year we hope to continue this upward momentum and learn a lot along the way, and I am honored to fill David’s place at LPRD as he moves upward with his internship at Blue Origin. We’re all very proud of him, and give our best wishes for his success.

Happy Holidays from all of us here at LPRD, and we hope to see you back here next year!

Subteam Spotlight: Nitrous

This semester has been a very productive one for Nitrous subteam.  Coming in as a brand new team, we had a lot on our plate to accomplish.  At the moment, we are slightly behind schedule; we were hoping to have fired the Mk1 nitrous engine by the end of the semester.  However, we have made excellent progress towards that goal.  Currently, most of our machining is complete, and the rest should be completed quickly at the beginning of next semester.  

We have ordered/received all of our hardware for the test stand conversion too and should be able to complete the setup and conversion at the beginning of next semester as well.


Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 12/4/16 – Winter’s Coming

Hi all!

LPRD Rocketry has been making some steady progress over the past couple of weeks, but the weather has been doing it’s darndest to stop us. While we have a rocket ready to fly to further test out our asymmetric thrust concept, the weather isn’t cooperating, so that’s a shame. Similarly, further testing on our engines becomes more and more difficult as the temperatures drop and the snow falls, so we’ll have to spend some time thinking hard about whether we want to test out in the cold.

However, I (David) will not be joining them in that decision. In addition to complaining about the weather in Minnesota, this post is my announcement that I will be taking a gap year from school to pursue some other career development, and the team will be transitioning into the capable hands of Glen Smith and the rest of our leadership team. Glen has been here for about a year and currently leads the flight team, but he will be stepping up into the communications, public outreach, and administrative role I currently fill, so look forward to hearing from him in the future! Glen’s a great guy, and of all the people at this university, I could not imagine a better person to further our mission of rocketry and our culture of relentless practical learning.

This will be my last post to the LPRD Rocketry blog, because the next one you will see will be from Glen! I’m very proud of what we’ve managed to accomplish and deeply proud of the people who have worked and grown with me to create the organization we have today. With that said, I’ll pass the mic over and let Glen update you on Flight Subteam in the subteam spotlight.

Subteam Spotlight: Flight

Glen Smith of LPRD Rocketry with high power asymetric thrust rocket to test unique booster concept

This week on Saturday we plan on launching our asymmetric rocket. After a few delays we are just about ready to go, with a few last minute preparations to be finished. The main problem that we were facing was manufacturing the custom rocket parts we needed to make the asymmetric section of the rocket. With the resources in the Exceed lab, one of our student shops on campus, we were able to make all the needed parts. The 8 degree angle needed for some of our parts was challenging to cut precisely, but we came up with the solution of using a few pieces of wood as a brace in the shape of a triangle to hold the flame tube in position for the cut. This Saturday will be a huge milestone towards flying a liquid rocket engine, if the weather holds out. 

Member Spotlight: Aaron Breidenbach

LPRD Rocketry's Aaron Breidenbach performing some sort of physics demonstration with a vacuum

Don’t ask me what this is; I just receive the pictures and put them in

My name is Aaron Breidenbach.  I am a third year physics major at the University of Minnesota.  Being a member of LPRD rocketry has given me a great opportunity  to apply my knowledge of physics to a practical application.  I have always been fascinated by fluid mechanics and advanced kinematic problems in my coursework, and I think that it is great being able to see the theory go to work to put a rocket high up in the air.  

Other than LPRD rocketry, I enjoy researching new complex magnetic materials and teaching other students as a TA for physics I.  I also like doing physics demos for elementary age students on the weekends too (that’s me in the vacuum bag!).  If I had time to sleep I’d probably like that too!

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 11/6/2016 – Onwards and Upwards

Hi all!

Some bittersweet news to start off with: we have decided to move on from recovering video from the firing on our own event, but we have some video recorded from inside the bunker. While this means there will unfortunately be no direct video of the firings for us to share with you, the good news is we will begin putting out video taken at other times during the day.

Below is a video taken by Vadim from inside the bunker of our second successful firing.

We’ll be following up in these next couple weeks with some recorded analysis and videos from around the test stand after the tests. This will let us move forward and start focusing on the next round of tests, but for now, let’s get into the spotlights!

Subteam Spotlight: Avionics

Autonomous Control being our major goal this semester, our main push so far has been integrating major sensors that would be required to provide the necessary feedback to having a functioning control loop. This includes pressure sensors, position feedback, force, temperature and motion sensors. Position feedback involves just having a potentiometer fixed on a valve with the moving shaft of the valve rotating the knob on the potentiometer. This rotation would change the resistance of the potentiometer which would reflect in a change in voltage. Knowing that a change in voltage is linear to the angle of the valve, we would be able to determine the angle at which the valve is opened. This setup is shown in Figure 1.  

LPRD Rocketry valve modification for position feedback on control valves with potentiometers

Figure 1

Pressure gauges along the line would come under an “Ambient Conditions Monitoring System” to ensure proper working of our systems. This setup is shown in Figure 2.

LPRD Rocketry electronic pressure gauge for feedback and control

Figure 2

To measure the thrust that the Rocket engine makes, we intend to use a load cell which is essentially a wheatstone bridge with 3 fixed resistances and a variable resistance that changes with a change in weight. Using a differential amplifier, we could measure the voltage difference and a linear conversion would give the corresponding weight. We are using an HX711 amplifier for this purpose. To calibrate our sensor, we have used a few standard weights like the ones shown below.

Weights for calibrating LPRD Rocketry test stand strain gauge

Eventually, we hope to transfer our prototype into a circuit board which would not only provide a more stable setup but would also expose our members to an industrial EE design cycle something which is often ignored in a student group project. Look for more updates on our page and in case you are an electronics enthusiast please do check us back soon to see what we’ve been up to!

Member Spotlight: Anna Bialke

Anna Bialke of LRPD Rocketry's Nitrous subteam

My name is Anna Bialke, and I am a freshman intending on studying aerospace engineering. I joined LPRD Rocketry because I find space travel intriguing and wanted some hands-on practical experience. I can play flute, bassoon, tuba, and currently play baritone in the University Marching Band. During the summer, I play euphonium in Minnesota Brass Drum Corps. Learning about new celestial objects that different spacecraft have discovered is deeply fascinating, and I want to pursue a career that would allow me to contribute to this continuing discovery of the universe.

Anna bialke of LPRD Rocketry's nitrous subteam

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 10/30/2016 – Happy Halloween!

Hi all!

Happy Halloween!

Hope everyone has awesome plans for Halloween! LPRD Rocketry has been busy too working on spooky and terrifying things like computational fluid dynamics. The nitrous subteam has been working hard on getting their designs fully defined, and CFD software is one of the tools they’re using to do so. I’ll let them tell you about it!

Subteam Spotlight: Nitrous

These past few weeks, the Nitrous Subteam has made a lot of progress.  At this point, we are nearly ready to begin machining our first Mk1 nitrous engine.  Using some of the references available to LPRD, we were able to solve for most of the parameters for our first engine.  Compared to the oxygen-based Mk1 engine, the nitrous engine burns with less kerosene and significantly more oxidizer.  Hopefully, this should increase the benefits from utilizing the higher density of nitrous oxide by maximizing the amount of propellant we can liquify.  Simulations for the nitrous oxide injectors are going through their final refinements, and current results are about what we were expecting.  This image shows the pressure against the simulation walls and the gas jet velocity.

Nitrous Team Engine Simulation Results LPRD Rocketry oxidizer injector holes

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 10/23/16 – T-t-t-test Staaaaand.

Hi all!

In addition to doing some pre-testing of our new position feedback on our control valves, we just moved our new vertical test stand into Akerman 15 this weekend! Thanks to Dan and Jame for doing such a great job on it. It took quite a bit of cleaning and rearranging to find a place to put it, but we finally got it there in the end.

Unfortunately, no pictures of the test stand (since I forgot the camera in Akerman – oops!), but I’ll make sure to get them uploaded as we begin to assemble the piping and plumbing onto the test stand.

In addition, it looks like it’s going to take longer than expected to make the necessary modifications to valves to run them automatically, so it looks like it’ll be tough to get in a firing with this test stand this semester.  We’ll keep everyone updated though, and hopefully we’ll have this thing up and running lickety split.

Subteam Spotlight: Flight

This past week, the flight subteam has been working on building two experimental rockets which we hope to launch in two weeks.  The first of these rockets is an asymmetric rocket design; it includes an additional nozzle that extends outward from one side of the rocket.  It’s purpose is to provide additional thrust to achieve greater launch speeds.  Although seemingly counterintuitive, this nozzle is located at the center of mass of the rocket, so it will not exert any torque and cause the rocket to rotate in flight.  

LPRD Rocketry asymmetric rocket fin mount

The purpose of the second rocket shown is to test an experimental roll control design.  If successful, we expect this to greatly increase the in flight stability of our rocket, and we could potentially use this design to achieve better flight stability for our main rocket.

LPRD Rocketry roll control avionics bay open


LPRD Rocketry roll control avionics bay


– Aaron Breidenbach, Flight Subteam Secretary

Member Spotlight: Ryan Ichinose

LPRD Rocketry's Ryan Ichinose

My name is Ryan Ichinose, but my baseball team has always called me “Ichi,” and I kind of like it. I think one of the biggest things to know about me is that I love pretty much anything that has anything to do with the sky; helicopters, airplanes, rockets, planets, moons, even the weather is a bit interesting. I definitely want to make a career out of the sky, I don’t really know how, hopefully either flying helicopters or engineering amazing flying things, but I think I’d be satisfied with a lot of different jobs, and who know where the wind will take me. . .

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!

Update 10/16/2016 – Featuring…Us!

Hi all,

Short update this week (no subteam spotlight or member spotlight), but we do have something we think is pretty exciting. Protolabs’s case study featuring us is now published and can be seen here! For those of you who don’t remember or haven’t been with us that long, Protolabs is the company that graciously 3D printed a regeneratively cooled rocket engine for us! It’s an incredibly cool (in both senses) part, and we’re incredibly grateful they were willing to donate their services to us.

LPRD Rocketry 3D Printed Rocket Engine

LPRD Rocketry member messing around with 3D printed rocket engine


In other news, we are still working on seeing if we can’t recover any video from the firing we just ran. While it would be quite the disappointment if we didn’t get any, we do have some other data which we will be analyzing and hopefully deriving information from.

In the mean time, our subteams are working hard on progressing towards the next problem. With any luck, we will begin testing out our new, bigger engine and test stand in the coming weeks in preparation to run a firing with Orbital ATK to test out our new, 1000 newton engine. Regardless of whether we retrieve the video, the knowledge we gained on igniting the engine will carry over and help make the firing of this next engine all the more successful!

-David Deng

Previous                            Next

Keep Up!

Want to get an email notification when we post updates? Click this link here and fill out the form!