PSAS is a student aerospace engineering project at Portland State University. We're building ultra-low-cost, open source rockets that feature some of the most sophisticated amateur rocket avionics systems out there today.
Meetings take place almost every Tuesday at 7pm at PSU. Come join us anytime! See our Schedule section for detailed information on the where and when we meet.
To learn about all the cool stuff we've done over the past decade or so check out About PSAS. To get an idea of how you might like to contribute, read Getting Involved. To e-mail us, write us or subscribe to our mailing lists, use the Contact section. For technical details on how PSAS is organized, you might enjoy the Teams section.
We are an educational, not-for-profit group and we rely on support from our community to move forward. If you have the means please consider donating something to our effort. Every little bit helps! All donations are tax deductible.
Our next launch is scheduled for June 30th, 2013 in Central Oregon about 45 minutes past Bend on highway 20.
This is a major test for our avionics system. On the launch manifest is a new Atom-based flight computer, the first of our ARM-based microcontroller boards, 802.11A telemetry, and a new Lithium polymer battery pack. We're trying to fit in other upgrades as well, including the RocketTrax antenna pointer and a new launch tower computer. Lots of things to test!
For all the details refer to our L10 Launch Logistics Page.
Latest meeting notes (add):
... and here's our news archive: History
On July 31st 2011 we headed back to Brothers, OR to launch our rocket again with the same roll control as the previous launch, but this time with much of the full flight computer (years in the making) in place and running.
Unfortunately the rocket motor failed on ignition ejecting the fuel (unburnt) from the rear of the rocket. The force of the depressurization lifted the rocket about 10 meters into the air, after which it came down fairly hard. We're still repairing the minor damage, which included a ripped parachute. According to our motor's manufacturer, we were accidentally sold recalled fuel grains. Although they're providing us with a new motor casing and fuel, we're all very disappointed that this was the cause of the failure.
Our last successful launch was in October of 2010 and was a complete success. Here is onboard footage along with a rendering of the orientation of the rocket from one of the IMU's and graphs of the roll control computers data:
Brothers Oregon launch with the same roll control as the previous launch, but this time with much of the full flight computer we have been planning for years in in place and running. This included the PowerPC flight computer, a Hemisphere Crescent GPS receiver board, and our new 2.4 GHz Amateur TV broadcast system with overlay.
Unfortunately the rocket motor failed on ignition, ejecting the fuel (unburnt) from the motor casing. The force of the depressurization lifted the rocket off of the launch rails, to about 30-40 feet into the air. Although the drogue parachute did eject, the rocket came down fairly hard and suffered minor damage to the fin canister and aeroshell.
Successful launch with a roll control module and "spin can" on Sunday October 17th, 2010 at Oregon Rocketry's (OROC) Brothers' launch site.
On-site video analysis confirmed that the roll control module and spin can worked!
Launch from the Brothers launch site. The roll control was only a partial success. The mechanical and software systems appeared to work as designed. However we appeared to experience a "control reversal" where fins placed in the counter clockwise arrangement caused the rocket to rotate in the clockwise direction and visa versa. The cause of this problem is aerodynamic in nature and a fix was conjured up for the next flight.
We successfully launched at Oregon Rocketry's Brothers Launch Site. After several years of rebuilding the airframe along with a redesign and heavy testing of our recovery system we had a very successful flight!
We finally launched "Launch Vehicle No. 2" (LV2) with a complete avionics system to over 18,000 ft (above ground level) on August 20th, 2005, outside of Brothers, Oregon. Technologically speaking, the flight was a stunning success in the sense that the avionics worked far better than we expected. Unfortunately, due to a failure in the nose cone ejection system, the rocket was destroyed when it hit the ground at over 500 mph.
The PSAS team drove out to the Black Rock Desert of Nevada to attempt two launches of Launch Vehicle No. 2 (LV2): LV2.1 which was flown in September of 2002 and LV2.2 which was a new airframe. After all day work and integration sessions in the middle of the desert on Friday and Saturday, LV2.2 was launched on an "O" motor Sunday morning as an airframe only (i.e., without the LV2 avionics package). Unfortunately, LV2.2 was destroyed about 8 seconds into flight near 5,000ft and between Mach 1 and 2. We think the fin canister tore off because of the modifications we did in order to make it fit on the the "O" motor case. The nosecone, commercial flight computer, and 2m uplink board were recovered, but the rest of the rocket was destroyed. The failure of LV2.2 forced us to scrub the launch of LV2.1 with the avionics package because of the loss of the parachutes and unknown condition of the commercial flight computer and 2m uplink board.
After more than two years of work, "Launch Vehicle No. 2", or LV2, had a near perfect first flight. On Sunday morning, September 22, 2002, the Portland State Aerospace Society launched LV2 at an experimental amateur launch held in the Black Rock Desert of Nevada. This first flight of the LV2 design was an "airframe only" test and proved that the airframe would handle the acceleration and aerodynamic loads of flight (including crossing the sound barrier). This flight of LV2 contained no avionics except a commercial flight computer and the LV1b 2m radio uplink system. The commercial flight computer, an Emmanual Avionics unit, recorded a top speed of 900mph (Mach >1) and an apogee (maximum altitude) of ~ 18,000ft.
LV2 was recovered succesfully, but during the soft landing on the main parachutes the airframe was slightly bent at the interface between the fin canister and avionics module.
Successfully launched to approximately 12,000 feet on October 7th. This launch verified new hardware including a 6 degree of freedom Inertial Measurement Unit incorporating accelerometers and gyroscopes in the X, Y, and Z axis. Also on board was a GPS system that tracked the course of the flight while simultaneously transmitting the position down to the ground via an "off the shelf" 900MHz downlink along with an Amateur Television signal. Initial analysis of data is very good to apogee but shows some post-apogee data and video drop out due to possible damage of antenna array by recovery system deployment.
LV-1 rocket equipped with IMU sensor package and ATV transmitter was launched to an altitude slightly over 12,000 feet above ground level. The flight went well. All systems operated correctly and the rocket was retrieved completely intact and is ready to launch again. It was a near vertical flight. The Amateur Television transmitter gave us a live view of the entire flight, from motor ignition to payload touchdown (8 min 1 second). The flight computer streamed down real time data from the on board pressure sensor, 3 dimensional accelerometers, and 3 dimensional gyroscopes. The graphed data closely matches simulation data. Our altitude was a little higher than we expected according to the pressure and accelerometer data but we are not complaining. The recovery system worked nearly as planned and everything came down safe.The images we got back from the rocket are amazing! We had a great team out there and managed to set up the site, integrate the systems, launch, and recover the rocket and completely tear down in less than 24 hours. We really operated well as a team. We are now going through the process of analyzing our data and reviewing our flight and procedures looking for places to improve. We should also be updating the site on all our LV-1 data and schematics. Overall we consider LV-1 a success and are taking what we have learned from this and applying it to LV-2.
PSAS First rocket and first flight.
Overall the flight was successful. There were a few things that went wrong. The flight could have been more stable. I believe the instability was do to using a modified kit rocket. The fins should have been scaled up somewhat to allow more control surface. They were too small for the low airspeed we had. The low airspeed was due to a very heavy 12.2 lb vehicle. Another problem was our acceleration data from the PIC microcontroller sent down over the audio channel was not frequency shifted at all. Upon later inspection we found a two wires that had become shorted together. These problems will be fixed for the next flight
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