(Llano de la Paciencia)

Our new odometer seems to work! Real Time computing expert Mark Sibenac today unveiled a new means of tracking our distance covered across the desert. Although not necessarily as precise as the other components that comprise our position estimation subsystem, it compared favorably with the trip distance measured by the d-GPS sensors today; their two answers differed by less than two percent at several times throughout the day. This will enable us to provide coarse, but nearly correct, estimates of total distance travelled each day. I'll keep you in suspense about today's mileage until the bottom of this update.

Today Nomad drove itself autonomously over 1720 meters of terrain; that's over a mile of driving through unknown terrain! Some of it was accomplished during the lunch break at the Carnegie Science Center, and some at the end of the day. Not all of the autonomous navigation capabilities have been demonstrated; it remains to enable "point turns", when Nomad will rotate in place without moving forward or backward. That capability is needed when Nomad encounters an obstacle that it cannot steer around in time (e.g., a cul-de-sac), and since it is not yet working it did have a *little* help today; any time it got stuck in a situation that demanded a point turn, one of our expert drivers helped it out. The system needs some more fine-tuning, but this ability of Nomad to steer itself through unknown terrain will prove invaluable to future robotic planetary explorers. NASA's Sojourner robot, due to arrive on the surface of Mars at 1307EST on 4 July, already employs limited autonomy capabilities. But whereas the distance Sojourner is expected to traverse totals tens or hundreds of meters over many days, today Nomad demonstrated its ability to navigate 1.7 kilometers (just over a mile) in under three hours.

We have found yet another treasure in the Atacama; the gas can that was lost yesterday. And the grand total distance covered by Nomad today, either driven by remote operators or steering itself, is:

4.397 kilometers

Tomorrow we expect to relocate to our second hilltop station for this traverse, at a point about 15 kilometers south of our current base camp.

Last Modified on: Wed Jul 9, 1997