Field Experiments with the Ames Marsokhod Rover Daniel Christian 1 , David Wettergreen, Maria Bualat, Kurt Schwehr 2 , Deanne Tucker, Eric Zbinden 1 Intelligent Mechanisms Group NASA Ames Research Center, MS 269-3 Moffett Field, CA 94035-1000 USA 1. Caelum Research Corporation 2. Recom Technologies, Inc. Abstract In an ongoing series of field experiments, the Ames Marsokhod rover is deployed to remote locations and operated by scientists in simulated planetary explora- tions. These experiments provide insight both for sci- entists preparing for real planetary surface exploration and for robotics researchers. In this paper we will pro- vide an overview of our work with the Marsokhod, describe the various subsystems that have been devel- oped, discuss the latest in a series of field experiments, and discuss the lessons learned about performing remote geology. 1 Introduction A terrestrial geologist investigates an area by systematically moving among and inspecting surface features, such as out- crops, boulders, contacts, and faults. A planetary geologist must explore remotely and use a robot to approach and image surface features. Close-up inspection of remote planetary sur- faces is a key part of understanding the geological processes at work in our Solar System. Upcoming NASA missions, as well as the recent Mars Pathfinder landing with the Sojourner robot, offer planetary scientists opportunities to use mobile robots to make close observations of surface features, and to help answer long-standing questions regarding planetary for- mation. The Intelligent Mechanisms Group (IMG) at NASA Ames Research Center (ARC) has been developing capabilities and control systems in order to research and evaluate the scien- tific exploration of other planetary surfaces. A series of mis- sion simulations have been performed where the robot is located at a remote field site, but controlled from ARC (or other sites). In each test, the abilities of the robot, the effi- ciency of remote control, and the accuracy of mission simu- lation have improved. Initial tests in Kamchatka, Russia in 1993 tested virtual reality remote control of the robot and imagers. The Amboy crater test in California in 1994 investigated remote science team interaction in the presence of significant time delays. The Kilauea Volcano test in Hawaii in 1995 added a manipu- lator to the vehicle and more advanced control modes [Hine 1995]. The most recent test in the Painted Desert region of Arizona in 1996 further improved sensors, control modes, onboard autonomy, sample handling, and remote science simulation. 2 Marsokhod systems The research emphasis using Marsokhod (see Figure 1) is on software and sensors for remote exploration. While Mar- sokhod is larger than the size currently being considered for Mars missions, little or no miniaturization is needed to test many common field instruments as part of the robot. This enables more rapid, inexpensive research into the field effec- tiveness of different sensor, actuator, and software configura- tions. Figure 2 shows Marsokhod with a Sojourner model and the Koala micro rover for comparison. Figure 1: Ames Marsokhod in Arizona