Jeng Yen

Terrain Modelling for In-situ Activity Planning and Rehearsal for the Mars Exploration Rovers

Immersive environments are being used to support mission operations at the Jet Propulsion Laboratory. This technology contributed to the Mars Pathfinder Mission in planning sorties for the Sojourner rover and is being used for the Mars Exploration Rover (MER) missions. The stereo imagery captured by the rovers is used to create 3D terrain models, which can be viewed from any angle, to provide a powerful and information rich immersive visualization experience. These technologies contributed heavily to both the mission success and the phenomenal level of public outreach achieved by Mars Pathfinder and MER. This paper reviews the utilization of terrain modelling for immersive environments in support of MER

Driving on Mars with RSVP

The rover sequencing and visualization program (RSVP) suite of tools has been a critical factor in the success of the Mars exploration rover (MER) missions. It would be impossible to prepare the large command loads each sol without the capabilities that it possesses. It has proven to be robust and easy to use and capable of answering key questions about sequence validity and constraints. Certainly, training is required to use RSVP, but this is primarily in the general area of command sequencing and rover operations. Once these concepts are understood, RSVP feels natural for building sequences. RSVP has met its prime requirements of supporting rapid assimilation and understanding of the terrain and operational constraints, rapid sequence generation and validation, and production of documentation and archival products. This can be seen in the very limited number of sols lost due to errors in the command sequences. The success of the MER mission and the tremendous amount of science data collected attest to the capability of RSVP

The Best of Both Worlds: Integrating Textual and Visual Command Interfaces for Mars Rover Operations

A Mars rover is a complex system, and driving one is a complex endeavor. Rover drivers must be intimately familiar with the hardware and software of the mobility system and of the robotic arm. They must rapidly assess threats in the terrain, then creatively combine their knowledge of the vehicle and its environment to achieve each days science and engineering objectives. To help the Mars Exploration Rover projects rover drivers meet their goals, the software we developed to drive the rovers - the Rover Sequencing and Visualization Program, or RSVP - combines two representations of command sequences, one textual and one using three-dimensional graphics. Changes to one representation are instantly reflected in the other, and the combinations advantages exceed the mere sum of the parts: the different representations offer different levels of abstraction, engage different areas of the drivers brain, and complement each others strengths. This combination plays a crucial role in simplifying a complex feat of interplanetary exploration

Mars Exploration Rover mobility and robotic arm operational performance

Increased attention has been focused in recent years on human-machine systems, how they are architected, and how they should operate. The purpose of this paper is to describe an actual instance of a practical human-robot system used on a NASA Mars rover mission that has been underway since January 2004 involving daily interaction between humans on Earth and mobile robots on Mars. The emphasis is on the human-robot collaborative arrangement and the performance enabled by mobility and robotic arm software functionality during the first 90 days of the mission. Mobile traverse distance, accuracy, and rate as well as robotic arm operational accuracy achieved by the system is presented.

Sequence rehearsal and validation on surface operations of the Mars Exploration Rovers

This paper describes the innovative numerical algorithm and the command sequence simulation of the MER mission for surface operations.

The design and architecture of the Rover Sequencing and Visualization Program (RSVP)

The Rover Sequencing and Visualization Program (RSVP) is a suite of applications for composing, visualizing, and simulating sequences of spacecraft commands. The successor to the Rover Control Workstation software used in JPLs highly successful 1997 Mars Pathfinder mission, RSVP provides fast command editing and highly accurate simulation for Mars rover missions. Though it shares some conceptual and architectural similarities with its 1997 predecessor, RSVP was implemented from scratch for JPLs 2003-04 Mars Exploration Rover (MER) missions. RSVP is the software used to “drive” the MER rovers on the Martian surface, and was also used to command them during their cruise phase.

Data Visualization for Effective Rover Sequencing

The Rover Sequencing and Visualization Program is a suite of tools for the commanding of planetary rovers which are subject to significant light time delay and thus are unsuitable for tele-operation. The two main components of the program are the Rover Sequence Editor and HyperDrive. This paper focuses on HyperDrive, the immersive visualization component of the system. HyperDrive fuses multiple data types returned from the vehicle in order to facilitate an operator understanding of the current environment and past rover performance, so that safe effective command sequences for successful future rover activities may be generated on a tight tactical timeline. Multiple display and task specific interaction modalities are provided to most efficiently present relevant spatial and time series data to the sequence builder

Risk-aware planetary rover operation: Autonomous terrain classification and path planning

Identifying and avoiding terrain hazards (e.g., soft soil and pointy embedded rocks) are crucial for the safety of planetary rovers. This paper presents a newly developed ground-based Mars rover operation tool that mitigates risks from terrain by automatically identifying hazards on the terrain, evaluating their risks, and suggesting operators safe paths options that avoids potential risks while achieving specified goals. The tool will bring benefits to rover operations by reducing operation cost, by reducing cognitive load of rover operators, by preventing human errors, and most importantly, by significantly reducing the risk of the loss of rovers. The risk-aware rover operation tool is built upon two technologies. The first technology is a machine learning-based terrain classification that is capable of identifying potential hazards, such as pointy rocks and soft terrains, from images. The second technology is a risk-aware path planner based on rapidly-exploring random graph (RRG) and the A* search algorithms, which is capable of avoiding hazards identified by the terrain classifier with explicitly considering wheel placement. We demonstrate the integrated capability of the proposed risk-aware rover operation tool by using the images taken by the Curiosity rover.

Updates to the rover driving tools for Curiosity

The Rover Sequencing and Visualization Program (RSVP) is a tool suite used for building command sequences for the Mars Science Laboratory rover Curiosity. RSVP was previously used for other missions and for in-house research projects and proposal efforts. RSVP has undergone extensive modifications and enhancements over previous versions in order to support more challenging requirements and to make it more adaptable for future missions. This paper will provide a brief overview of many of the specific enhancements made for the MSL mission.

Physical-based simulation for Mars Exploration Rover tactical sequencing

The Mars Exploration Rover (MER) mission has returned tremendous scientific information on a daily basis, owing to the efficient sequencing capability of the ground system tools. For planning the mobility and instrument deployment device (IDD) sequences, physical-based simulation is applied to achieve fast and effective sequencing of complex rover and IDD maneuvers. The sequence rehearsal tool of the Rover Sequencing and Visualization Program (RSVP) is based on modeling and simulation of the multi-body mechanical systems. Using configuration kinematics (CK) and 3D terrain models, a methodology was developed to support a real-time, interactive graphics mode for the visualization tool. The sequence simulation is carried out using the on-board flight software modules for realistic rover behavior. This enables the scientists and rover planners to effectively develop the command sequences to maximize the science return of the MER mission while maintaining rover safety. This paper describes the innovative numerical algorithms and the command sequence simulation used by the MER mission for planning surface operations.