Recap of 2009 Competition, by Steve Burrows
Written by Tom Nugent on Wednesday, November 18th, 2009
LaserMotive Recap
by Steve Burrows, LaserMotive team member
After three years of hard work nights and weekends, team LaserMotive arrived at Dryden feeling ready to rock and roll. Every system had been tested, checked, and packed along with backups for every conceivable contingency. We were ready, we were pumped, we hadn’t had time to catch up on sleep yet. Having seen only hints of what the other two teams were fielding, we were wary of our worthy competitors, yet confident of our choices.
We all arrived in Mojave Saturday evening with hardware intact. Unpacking, acquiring badges, initial setup, all went well on Sunday. We have done the drill before, just not in such an amazing place! Final setup and alignment went very well on Monday and Tuesday, and we were the first team to complete vertical laser alignment.
Racing the first day (Wednesday) handed us our first set of challenges. Early in our window, the laser control computer and the power supplies for our Dilas lasers stopped talking to each other properly. Tom Nugent, our laser operator and company co-founder, raced to the laser trailer to manually set the power supplies. Now we were just like a ship at sea, with verbal commands given to the engine room from the bridge.
Moments after sorting the power supply issue, the climber refused to climb after beam on. Not having a clue as to what might be keeping Otis (our climber’s nickname) at home plate, we requested a recycle, with Dave Bashford, our chief climber technician, ready to run out. The instant Otis landed safely, our safety officer, Steve Beland requested clearance to check the climber, Dave raced out to Otis, plugged in a battery, turned him on, got normal operation, then switched back to the PV array then raced back to the truck. During this interval, we got the remote laser control working again, allowing Tom to return to the command center.
Clearance to raise Otis back for another start was asked for and given. Racetime was on again. Settling in quickly after the helicopter reached altitude, Nicholas Burrows, our beam tracker operator, signalled beam on! Otis was climbing at a pace that could get it into the 5 meter per second prize level, but all the extra weight put on Otis to protect against a bad landing took its toll on overall speed. Losing primary telemetry forced Carsten Erickson, laser focus operator, to convert feet to meters in his head as distances were read out from the backup telemetry system. Video by NASA from off the lakebed showed Otis hitting the top stop twice! We think that may have been caused by nervous hands on the drive remote control — our view of the climber did not show the two hits, all appeared normal. Otis descended without trouble to the bottom stop to a nice one point landing. The climbing feat was repeated, with nearly the same climb time. Otis landed back on the lakebed without much drama. Waiting just a moment, Steve Beland requested clearance from Test Operations for the Team to begin breathing again. Test granted the request, but for “shallow breaths only.”
Debriefing that evening, the team set strategy for the next day, and we considered changing the climber to a much lighter (but much less protected) configuration, if we thought that would give us a good chance at making the top prize. We decided to hold off on going that light until the very last moment, because it was looking like we might get a third window on Friday. Running formulas and calculations in his head, Team Genius and Laser Lead Jordin Kare determined that our slower than expected performance may be due to some simple parameter change in the laser focus control. Otis was readied with a new gear set and removal of the cameras, and the heavier protective support structure was left in place.
Performance on day two was slightly improved, but still short of the 5m/s target. We had to restart Otis again after he refused to climb at initial beam on. We still are not certain what was causing this behavior, and we really don’t like mysteries! We were surprised USST had to scrub their second attempt for the day; it sounded real serious. Watching KSCP, both days, kept us on pins and needles, because their effort looked closest to forcing us to share the prize. We had aborted the final run during our window because we were not making any speed improvements, and we were concerned about the state of our pinion gear. Aborting the climb turned out to be a good call, because the pinion gear was a gnat’s ass from failing! It had been abused so much for so long (we’d even flipped it around to get more wear out of the opposite sides of the teeth) that the teeth had been worn very thin, and the edges bent – it looked more like a waterwheel then a gear.
Right after our window ended, we pulled the trigger on switching Otis to his light-weight, more risky configuration. Dave Bashford called it the “steamboat race” mode, where non-essentials like the deck chairs and parts of the hull get thrown into the boiler to help us go faster. Jordin and Carsten Erickson (our laser focus operator) calculated Otis was borderline too heavy even in its vulnerable featherweight configuration, although there was some debate about degraded efficiency in our gears and elsewhere. Jordin also requested a gear ratio change. Grabbing everything we might need, Dave Bashford, Jordin Kare, Carsten Erickson, and myself, went to the hotel to begin removing everything not strictly required to keep Otis going up the race cable and descending under control. In addition to swapping in the lighter but less protective support structure, Dave and I worked through the night to remove well over an additional 300 grams, resulting in a weight loss of 800 grams! We also installed a tracking aid we called a spider, which consisted of eight thin rods with spots of retro reflective material; this made the net weight savings closer to 700 grams. Returning to the lake bed after pulling an over nighter, we knew there would be high risk for error. Eyes looked at everything, but a single, missed 1/4 inch titanium nut would end up causing us serious trouble.
Learning from the prior two windows, we “shook the chicken bones” over Otis before sending him up. Otis climbed immediately after beam on, but even we could tell he wasn’t climbing as fast as he should have after the changes. Then we saw an alarming puff, was it smoke or was is dust? Smoke. Immediate recycle was requested to see if there was anything that could be done, we also got word that the bottom stop was pulled up with Otis, somehow they got jammed. Riding the bicycle, Dave Bashford arrived first, instantly noticing a burnt out DC to DC converter. Running out right behind Dave, I arrived and began to rip out the foam material from the bottom stop, thinking it may have stuck to the sharpened titanium threaded rod sticking out the bottom of Otis. Dave then had me remove the DC to DC converter while he rode back to retrieve its replacement the other team members pulled from storage. In a matter of minutes, Otis was ready to fly again. Climbing not more than 20 meters, Otis let out smoke again and the remaining time was too small to try for any more repairs, so our chance at winning $1.1 million this time was ended.
Alone with our emotions, all we could do during the KCSP window was to sit on the edge of our seats and watch the Pirates make a last valiant attempt for the goal. They had us worried up until the very end. When their window ended, we congratulated each other on a job well done, then began packing rapidly — NASA wanted us off their lakebed right away!
One mystery with several potential causes will have to wait for more testing. We do know what caused our last race to become the worlds first laser powered vertical tractor pull: omitting the 1/4 inch titanium nut allowed the threaded rod coming out the bottom of Otis to slip into the cable slot of the bottom stop where it got caught. Next competition will find us getting more sleep. Further analysis strongly suggests that our main problem, though, was having too much laser power on our PV array at the start of the climb — we overheated our DC-DC power converter by pushing it well past its nominal power rating! Once we’ve had time to recuperate, we’ll spend a couple of weeks getting everything back into tip-top shape, ready for the next Challenge.
Entering the competition as the “corporate” team, LaserMotive is a group of passionate professionals committed to jump start the new industry of power beaming. Knowing there is a bright future with unlimited possibilities for power beaming kept us going along with the spirit of competition. We salute the efforts of our competitors, and share the sentiment of Kansas City Space Pirates leader Brian turner: we were here to compete and win.
LaserMotive team members able to make it to Rogers Dry Lake at Edwards AFB, and their primary assumed roles were: Tom Nugent, team leader and laser operator; Jordin Kare, team laser genius and chief engineer; Dave Bashford, lead climber technician; Nicholas Burrows, tracking operator; Carsten Erickson, laser focus operator; Steve Beland, safety officer; Bill Boyde, you name it, he did it; Steve Burrows, assistant climber technician; Mary Kay Kare, team mom. Please see http://lasermotive.com/?page_id=6 for the complete list of team members. Many had to stay in Seattle to work their day jobs, and we sure missed them!
LaserMotive team members are grateful for the hospitality and safe and smooth operations of our host, NASA Dryden Flight Research Center. We hope they can invite us again to complete the NASA Power Beaming Centenial Challenge — we now have a title to defend!