J. Balaram

The Rocky 7 rover: a Mars sciencecraft prototype

This paper describes the design and implementation at the Jet Propulsion Laboratory of a small rover for future Mars missions requiring long traverses and rover-based science experiments. The small rover prototype, called Rocky 7, is capable of long traverses, autonomous navigation, and science instrument control. This rover carries three science instruments, and can be commanded from any computer platform from any location using the World Wide Web. In this paper we describe the mobility system, the sampling system, the sensor suite, navigation and control, onboard science instruments, and the ground command and control system. We also present key accomplishments of a recent field test of Rocky 7 in the Mojave Desert in California.

The Rocky 7 Mars rover prototype

This paper provides a system overview of a new Mars rover prototype, Rocky 7. We describe all system aspects: mechanical and electrical design, computer and software infrastructure, algorithms for navigation and manipulation, science data acquisition, and outdoor rover testing. In each area, the improved or added functionality is explained in a context of its path to flight, and need within the constraints of desired science missions.

Rocky 7: a next generation Mars rover prototype

This paper provides a system overview of a new Mars rover prototype, Rocky 7. We describe all system aspects: mechanical and electrical design, computer and software infrastructure, algorithms for navigation and manipulation, science data acquisition, and outdoor rover testing. In each area, the improved or added functionality is explained in a context of its path to flight and within the constraints of desired science missions.

Enhanced Mars rover navigation techniques

Robust navigation through rocky terrain by small mobile robots is important for maximizing science return from missions to Mars. We are addressing this problem at multiple levels through the development of intelligent sequencing, sensor constrained path planning, natural terrain visual localization, and real-time state estimation. Each of these techniques is described and their complementary aspects discussed. Experimental results are provided from implementation on our Mars rover prototype operating in realistic scenarios.

Kinematic observers for articulated rovers

A state estimator design is presented for a Mars rover prototype. Odometry estimates are obtained by utilizing the fall kinematics of the vehicle including the nonlinear internal kinematics of the rover rocker-bogey mechanism as well as the contact kinematics between the wheels and the ground. Additional sensing using gyroscopes, accelerometers and visual sensors allows for robust rover motion state estimation. Simulation as well as experimental results are presented to illustrate the estimator operation.

A prototype manipulation system for Mars rover science operations

This paper provides an overview of a new manipulation system developed for sampling and instrument placement from small autonomous mobile robots for Mars exploration. Selected out of the design space, two manipulators have been constructed and integrated into the Rocky 7 Mars rover prototype. This paper describes the design objectives and constraints for these manipulators, and presents the finished system and some results from its operation.

Technology for robotic surface inspection in space

This paper presents on-going research in robotic inspection of space platforms. Three main areas of investigation are discussed: machine vision inspection techniques, an integrated sensor end-effector, and an orbital environment laboratory simulation. Machine vision inspection utilizes automatic comparison of new and reference images to detect on-orbit induced damage such as micrometeorite impacts. The cameras and lighting used for this inspection are housed in a multisensor end-effector, which also contains a suite of sensors for detection of temperature, gas leaks, proximity, and forces. To fully test all of these sensors, a realistic space platform mock-up has been created, complete with visual, temperature, and gas anomalies. Further, changing orbital lighting conditions are effectively mimicked by a robotic solar simulator. In the paper, each of these technology components will be discussed, and experimental results are provided.

Remote surface inspection system

An ongoing research and development effort in remote surface inspection of space platforms such as the Space Station Freedom is reported. The space environment and the types of damage for which to search are described. An overview of the remote surface inspection system that has been developed to conduct proof-of-concept demonstrations and to perform experiments in a laboratory environment is provided. Three technology areas are described: (1) manipulator control for sensor placement; (2) automated non-contact inspection to detect and classify flaws; and (3) operator interface to command the system interactively and receive raw or processed sensor data. Initial findings for the automated and human visual inspection tests are reported.<<ETX>>

Automated inspection for remote telerobotic operations

Automated inspection techniques being developed for surface inspection of remote space platforms are reported. The unique problems of performing visual telerobotic inspection in space are identified. An image differencing method to detect changes to surfaces over a period of time is presented, together with a scale-space technique for flaw identification. Examples from images of laboratory mockups of space platform modules are presented to illustrate the results.<<ETX>>

A run-time control architecture for telerobots

This paper describes the architecture and Ada language implementation of a process-level run-time control subystem for the Jet Propulsion Laboratory (JPL) telerobot system. The concept of run-time control in a combined robot-teleoperation environment is examined and the telerobot system at JPL is described. An Ada language implementation of the JPL Telerobot Run-Time Controller (RTC) is described by highlighting the functional behavior of the subsystem, defining the internal modules, and providing a functional flow time sequence of internal module activity.