Welcome to Robotics @ Maryland
R@M is the University of Maryland's student robotics team. We design and build autonomous robots to compete against other schools and organizations. The club formed in 2006; since then, R@M has grown to four robots and roughly 40 members.
Robotics @ Maryland membership is open to any UMD student, regardless of major. To get involved, contact any of our officers or come to a meeting.
Thank you to our generous sponsors!
News (see archive)
First Meetings for 2011-2012 Year (Happening in KIM1110)
Hello everyone! Welcome back to another school year and another year of building robots. As promised, here's a post telling everyone that the meeting will once again be in the Kim building in room 1110 (this is the large lecture hall on the first floor).
Those of you who came to the last meeting and saw the presentation do not need to come again, but a piece of advice I realized I may have forgotten to give you was that you should plan on bringing a laptop with you to the club.
Hope to see you there!
RoboSub Competition Orientation 2011
Hello from San Diego! The whole team has made it out to San Diego in order to participate in the 14th annual AUVSI RoboSub competition! It has been a bit of work unpacking and getting settled, but we have finished all that and are making last-minute preparations for the competition. Having registered and signed up for practice times earlier today, we are prepared to arrive at the TRANSDEC facility early tomorrow morning and show off all of the changes that we have made to Tortuga IV, thanks to all of our generous sponsors!
Here is a picture of the resort that we will be staying at for the duration of the competition:
Here is a picture of Kit working on the electronics of Tortuga IV:
With all of the great improvements that we have made to our vehicle, we are confident that we will be taking 1st place this year! Wish us luck!
Robosub Competition 2011 Approaches! A Big Post of Progress Updates
We have been rather light with our updates in the previous few months but that hasn't stopped our progress. We have got a lot done and a lot to talk about so let's get started!
First off there's the Doppler Velocity Logger (DVL) from Teledyne which we've spoken so much about. You may recall our previous post talking about installing it to our frame, and after some technical hiccups ranging from simple to disastrous we produced the image below using real-time velocity information:
This image was made with a team-member pushing the robot around the edge of the tank, and after about 10 minutes, approximately 50 meters of swimming, and his estimation of where we started, the combination of the workhorse of our controls system, the Memsense IMUs, and the DVL had only accumulated about 1m of error! We're still testing the limits of the error of our system, but if that were the limit of our error, 1m could easily be corrected with visual information. And that was only the first try!
Since producing the above image we have integrated the software changes, which had been written months in advanced, and the controls system now properly uses the velocity information to perform tasks. We are continuously refining the estimation and movement systems, but they have quickly reached the stage that we are ready to use the new controls mechanisms in our AI. Check back soon to see us demonstrating these new controls in a cool and/or interesting way!
Another huge leap forward in Tortuga IV's design was the new cameras. Sidus Solutions has been mentioned several times in previous posts on the subject, and now we can unveil what they've helped us bring to life:
These new camera housings are, if you forgive a bit of self-indulgence, amazing. Designed by our mechanical lead Chris Carlsen, they are depth-rated beyond 300 meters, eliminate the previous design's heat dissipation issues, and are essentially the smallest housing that could hold both the cameras and our control electronics. We'd like to reiterate our huge thanks to Sidus Solutions for helping us build these housings! The electronics inside also deserve some special mention.
Here you can see another pair of our sponsors who helped make the new design possible: Advanced Circuits, who provided the printed circuit boards free of charge, as well as TC Technologies, who provided their incredible Eqcologics firewire chips free of charge. These boards are what allow us to pass what is normally a matched-impedance signal through the relatively messy interface that is both of our Subconn bulkhead connectors. All of this effort is meant to yield pictures for the robot vision software, so how about some samples? Now, these pictures may not look very impressive, but to those roboticists out there reading this: I think you can appreciate the quality of these pictures.
Traditionally, we had a lot of trouble differentiating between the yellow and green buoy, but the difference in these pictures is much sharper than with the previous cameras, and you can see that the noise in any given pixel is very low.
The new cameras also have a much higher depth of field than the previous cameras, which gives clearer images at a distance. You can also see that while the orange pipes were easily distinguishable before, they now practically pop out of the screen.
As in the first picture, normally we have trouble distinguishing between the different colors, but they are now vibrantly different, even in our vision software.
And as in the second picture, this demonstrates from nearly 40ft away that last year's targets are still easily visible, and distinguishable.
For comparison, here is a picture from our old cameras:
It may appear that the color definition on this camera looks comparable, but the grainy nature of this picture is actually a side-effect of the small pixel size (the new cameras have 7.4μm × 7.4μm for the cell size relative to the original 5.6μm × 5.6μm). That shifting noise made by the small pixel size plus the color bleeding and giving "soft" edges lowered the consistency of the previous system. You can also see the vignetting around the three corners of our camera view that our old housings created.
So we hope you appreciate this big update and we're planning on having a few more updates before the competition where we'll show you more of what our robot is capable of!
To end this progress update, here are two images of Tortuga IV for comparison: the final version rendered in our Pro/Engineer computer-aided design software, and the nearly-completed robot "in real life". We're almost there!
Mini Grand Challenge 2011
Our ATV-sized robot Donatello was entered into the MGC 2011 at Penn State Abington. The majority of the course consisted of path following, orange cone avoidance, and object collision detection.
Despite the ominous weather that threatened to cancel the competition, our robot was quickly redesigned to handle rainy weather. We ended up completing a good portion of the track on our test runs using vision processing.
We were given two trials. Our first trial was successful in stopping in front of objects and had travelled down the first section of the path using a combination of LADAR and vision. Our second trial also only drove a portion of the track, with some new adjustments to the LADAR.
Of course, our entry was not without its problems. We had a difficult time recalibrating our LADAR to the new track. The speed of the robot was also not as thoroughly adjusted as we had hoped it would be. We did not have enough time to add in personality to the robot.
We ended up receiving 3rd place out of 7 competitors. Regardless, we hope to improve upon our designs for next year!
Advanced Circuits Sponsorship! DVL housing finished
So I'd like to start off this entry with some very exciting news: we are now being sponsored by Advanced Circuits!
R@M has been making use of the student deals offered through the 33each and 66each service since the club began, and we have always enjoyed the quality of manufacturing in the final product: Tortuga! Because all of our non-integrated electronics are custom designed and built, our robot is built on Advanced Circuits' technology. Now what did Advance Circuits sponsor us with? I'm glad you asked!
The eqcologics board
Since we are now developing new camera modules with Sidus Solutions, we need new electronics to power this device. We have designed a compact (1.45"x2.75") electronics section which is capable of transmitting 400Mbps firewire through the bulkheads using TC Technologies eqcologics chip. Currently, the boards are still being built (as shown above), and only have one of the three power sections populated. But we can now confirm that we properly designed the switching power supply section! We'll be debugging this design over the coming week and we're hoping to confirm any serious design mistakes quickly so that we can move forward with mechanical designs.
And finally some big progress jumps tempered with setbacks: the DVL housing has been completed! Longer rails had to be added to accommodate the addition, which was completed and the robot has been rebalanced.
Chris and Dan, installing the DVL
Unfortunately, after getting everything installed it turned out there was an issue with the cable connecting the main electronics to the transducer element. The offending cable has been sent back to Teledyne for repairs, and we're hoping to have the DVL taking measurements in the water soon!
Tortuga, ready for action!