Wheeled Platform Research Articles

Generation of Smooth Reference Trajectories for Unmanned Wheeled Platforms Considering Automatic Constraints On Velocity, Acceleration and Jerk

Generation of Smooth Reference Trajectories for Unmanned Wheeled Platforms Considering Automatic Constraints On Velocity, Acceleration and Jerk

Modeling and performance evaluation of mecanum wheel platform with reduced vibration and a robust path planning

Modeling and performance evaluation of mecanum wheel platform with reduced vibration and a robust path planning

Optimal trajectory tracking of tractor-trailer wheeled platforms taken into account wheel dynamics

Tractor-trailer wheeled platforms are recognized as articulated robotic systems which consist of a frontrunner active mobile platform (known as tractor) that pulls one or more passive platforms (known as trailers). Regarding to their novel features such as maximum load carrying capacity and minimum energy consumption, this category of mobile platforms is widely employed for conveying purposes and transportation. The presented article deals with path tracking optimization of the tractor-trailer platform using the indirect method of the optimal control. First, nonlinear motion relations of the modular platform are obtained considering kinematic constraints and inertia characteristics of the wheels. Then, the obtained dynamic equations are considered as constraints of the optimal problem, and as a result an appropriate objective criterion is determined for the optimal trajectory tracking. In the following, a proper solution for the optimal problem is developed and accordingly some simulations are presented. In view of the wheels dynamics, the obtained results reveal competency and applicability of the proposed procedure for the optimal tracking of the tractor-trailer wheeled mobile platforms.

Analysis of the influence of substitute fuels on properties operating conditions of military hybrid drive systems

The energy density of chemical batteries makes it difficult to rely solely on cheap and eco-friendly electricity for power in many applications, such as airplanes, long-distance trains, ocean vessels, and heavy equipment. Limited charging infrastructure and power generation capacity are also problematic. However, hybrid powertrains provide a solution by combining electric and internal combustion engines to achieve better fuel economy and similar operational characteristics to traditional engines. Hybrid systems can also use alternative hydrocarbon fuels , with all advantages of conventional engines. This study aimed to determine the impact of alternative fuels on the performance of a hybrid drive system for a military wheeled platform developed for operation in urban areas. The experiment found that substitute fuels, such as, F-34, and Jet A-1, were compatible but could result in increased fuel consumption, decreased energy efficiency, and negative environmental impacts due to higher exhaust emissions.

WiFi Similarity-Based Odometry

Odometry is commonly used in localization applications especially with wheeled platforms since encoders are readily available. It is often used by itself or fused with other sensor data to obtain a better estimate. However, its limitation is its exclusivity to wheeled platforms whereas it is often desired to have similar encoder odometry options on other systems. Given that WiFi is ubiquitous in most commercial and industrial areas, in this paper, a method is proposed for obtaining odometry from WiFi scans for position estimation. The method is not constrained to wheel robots such as the case for wheeled odometry and does not rely on the traditional fingerprinting method. The proposed method involves training a neural network model to predict the distance moved based on features extracted from WiFi scans in the environment. These distances moved are then summed up to obtain the trajectory. Experiments are conducted and the methods are evaluated based on Root Mean Square Error (RMSE). Experimental results showed that the proposed method is able to achieve an RMSE of at most 8.39m for the various test cases. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —This paper was motivated by the limited sensors available for odometry. Existing methods of odometry either require a wheeled platform or exteroceptive sensors to be placed outside of the robot so that it can see the environment. This paper proposes a new and low-cost method of performing odometry using a WiFi receiver and Inertial Measurement Unit (IMU) with a neural network model. This provides an alternative that exploits existing WiFi infrastructure and thus more flexibility in robot design without wheels and sensor placement constraints. We show how the features are selected as well as propose several similarity methods to choose from. We then show how the neural network model is trained and used during implementation. Preliminary physical experiments suggest that the method was able to obtain the trajectory of a robot in two different environments using the same model and different speeds.

Torque control of a wheeled humanoid robot with dual redundant arms

Most of conventional controllers are prone to consume more computational time for controlling a wheeled humanoid robot. A nonlinear trajectory control of a wheeled humanoid robot using a model-based controller with less computational load and energy consumption is presented in this article. The upper body of the humanoid robot consists of two 6 degrees of freedom redundant arms, a three degrees of freedom torso and a two degrees of freedom neck. The nonholonomic mobile platform consists of two actuated wheels and two caster wheels. Nonlinearity of the robot dynamic model and coupling between various branches of the upper body are taken into account. The dynamic model derived using Newton–Euler approach along with decoupled Natural Orthogonal Complement matrix approach is used to derive dynamic equations of the upper body and the wheeled platform. Zero moment point based stability approach is used for verifying stable motion of the wheeled humanoid robot with minimum energy and time consumption to complete a task. The proposed computed torque controller is compared with other similar controllers developed for the same robot model to prove advantages of the proposed torque controller. Simulation results are experimentally validated with the real robot.

Adaptive Algorithm of the Wheelchair-Verticalizer User Interface System

Purpose of reseach. Development of a scheme and adaptive algorithm for the operation of an intelligent humanmachine system for the user interface of a wheelchair-verticalizer, taking into account the physiological characteristics of the operator, the wheeled platform and the external environment.Tasks. The study of the physiological characteristics of human-machine interaction in people with damage to the musculoskeletal system. Design development and mathematical description of the joystick as a component of a human-machine system. Development of adaptive algorithm and software for the wheelchair user interface system. Methods. Using the method of finite-state machine to describe the algorithm of motion modes switches. The use of polynomial functions in order to obtain smooth laws for changing the setpoints for the device drives. The use of nonlinear sensitivity coefficients of the joystick handle to provide adaptive modes of movement of the wheelchairverticalizer. Results. In the course of the study, the modes of movement of a wheelchair-verticalizer were developed and described. The design scheme and principle of operation of the joystick are presented and described. The modes of operation of the human-machine system was described mathematically and graphically. The adaptive algorithm of the user interface system of a wheelchair-verticalizer proposed in the paper interpret joystick inclinations into setpoints signals for wheelchair drive controllers. The use of non-linear sensitivity coefficients of the joystick handle to provide adaptive modes of operation of the wheelchair, taking into account the features of the hands movement of people with impaired functions of the musculoskeletal system, the movement of the wheelchair and the state of environment, is described.Conclusion. The adaptive algorithms of the human-machine system and the modes of movement of the upright wheelchair developed within the framework of the work make it possible to increase the safety and smoothness of movement through the use of non-linear sensitivity coefficients of the joystick handle and smooth laws of setting influences obtained on the basis of polynomial functions.

Agricultural Autonomous Robotic Platform Motion Control

A model of the movement of a robotic platform adapted to the conditions of an industrial orchard is proposed. (Research purpose) Development of a motion control system for an autonomous robotic wheeled platform based on inertial and satellite navigation and traversed path calculation, which will allow it to move in an apple orchard and automatically perform various technological operations, such as fertilization, growth diseases control of, fruit harvesting. (Materials and methods) A mathematical model was developed to control the movement of a robotic platform, taking into account the turning radii of three types, the length of the arc of the performed circle, the speed of movement in the garden plantation rows using a garden electronic map. The method used allows implementing a program for the robotic platform automatic movement around a typical orchard using a minimum set of sensors, significantly reducing the load on the onboard computer processor and memory. Software, developed in the Python programming language, enables plotting the robotic platform route, displaying the movement trajectory, and indicating the positioning accuracy at each point in relation to the trees in the garden plantation rows, the movement speed and the wheel rotation angle. (Results and discussion) The robotic platform managed to autonomously pass the preset routes, while the interaction of the software and the robotic platform hardware was provided. A field testing of the developed software was performed. (Conclusions) The specified accuracy of the robotic platform positioning was confirmed for the 3.5-meter aisles of intensive orchards. The maximum deviation from the task map using satellite and inertial navigation system was 164 millimeters, which complies with the agrotechnical requirements for mechanized fruit harvesting.

Simulation of the Joint Movement of a Robotic-Towing Vehicle and an Aircraft Using Signals from an Optocoupler Matrix

Actuality. The heavy workload of airports with transport and cargo aviation creates a problem the land logistics, that seriously complicates the work of the airfield towing system and personnel working processes. That entails expences associated with delayed deliveries or equipment downtime. The usage of the automatic aircraft movement systems, which are capable of towing aircraft round the clock and quickly along the airfield, following the optimal trajectory allows to avoid such situations.Purpose of research. Creation of the mathematical model and the control algorithm for the autonomous joint movement of a wheeled aircraft towing vehicle and an aircraft, where the control is based on the signals of an optocoupler array.Methods. Achieving this goal required solving the following problems: describing of a dynamic model of wheeled bodies interconnected by an elastic element; creation of a feedback model based on a group of optocouplers detecting a contrast line; description of the logical conditions that allow determining the position of the object relative to the contrast line. To describe the dynamics of the wheeled platform, the equations of Lagrangian dynamics, as well as the numerical methods of mathematical modeling, were used. An optocoupler array is considered as a tool for estimating the position of the system relative to the contrast line.Results. A mathematical model, which explores the system movement and reveals the interaction of the system elements has been developed. An adaptive algorithm based on the discrete type feedback for the system managing is developed. An example of the control system when moving in a straight line with the passage of turns at an angle of 90 degrees is considered. A combined braking system in which the distributed brake efforts both on a aircraft and the tower are formed is proposed.Conclusion. As a result of the mathematical modeling, it was found that the system of wheeled bodies, bound by the force of elasticity, is able to perform controlled movements along a straight line and when passing sharp turns, based on the readings of the optocoupler matrix; corresponding graphs are shown.

Control of wheeled platforms straight motions taking into account jerk restrictions under speeding-up from the state of rest

The generalized mathematical model of wheeled platforms straight motions on the ideal horizontal plane under speeding-up from the state of rest mode is proposed, and the controls satisfying the restrictions of motion jerks are find. The pure mechanical and electromechanical wheeled platforms are considered, as well as the computer simulations of the researched processes are made. The jerks restrictions are reduced to limiting the value of the wheeled platform acceleration time derivative. The proposed approaches are based on the holonomic systems mechanics and on the electromechanical analogies allowing to consider the different kinds of the wheeled platforms taking into account the electric on-board systems like the drive electric motors and the control systems by using the Lagrange equations of second kind. The examples of the proposed approaches using to define the controls satisfying the jerks restrictions under speeding-up from the state of rest are considered for the pure mechanical and electromechanical wheeled platforms. It is obtained the inequality allowing to chose the instantly supplied driving mechanical couple which will provide the admissible jerks of the motion of the wheeled platform under speeding-up from the state of rest. It is shown that the rolling friction and the viscous damping are the principal causes of the wheeled platforms jerks under speeding-up from the state of rest. It is obtained the inequality defining the voltage instantly supplied on the drive electric motors which will provide the admissible jerks of the motion of the electromechanical wheeled platform during speeding-up from the state of rest, and it is shown that the proposed general approaches are suitable for considering the different kinds of wheeled platforms. The computer simulations of the processes of speeding-up from the state of rest for the electromechanical wheeled platform are considered to show results correctness and to illustrate satisfying the restrictions of the motion jerks. The obtained results of the computer simulations are in the full agreement with the well-known fundamental property inherent for the wheeled platforms. The results for the jerks show that the maximum value of the jerk is really at the initial time as was suggested before, and it is shown that the jerks values at the initial time obtained by using the computer simulations are in full agreement with the theoretically defined correspondent exact values. The big jerks of the considered electromechanical wheeled platform are due to the voltage instantly supplying on the drive electric motors at the initial time, and it is understandable that limiting of such instantly supplied voltage value cannot provide any wished small jerks. The smooth time depending for the voltages supplying on the drive electric motors are required to provide any wished small jerks of the electromechanical wheeled platforms.

Robotic Platform for Horticulture: Assessment Methodology and Increasing the Level of Autonomy.

The relevance of the study is confirmed by the rapid development of automation in agriculture, in particular, horticulture; the lack of methodological developments to assess the effectiveness of the introduction of robotic technologies; and the need to expand the functionality of mobile robots. The purpose of the study was to increase the level of autonomy of a robotic platform for picking apple fruits based on a new method, develop a system of factors to determine the effectiveness of the introduction of robots in horticulture, and develop a control system using integrated processing of onboard data. The article discussed the efficiency factors for the introduction of robotic systems and technologies in agricultural enterprises specializing in horticulture within the framework of projects with different budgets. The study sample consisted of 30 experts-enterprises that have implemented robotic platforms and scientists specializing in this field. Based on an expert survey of enterprise specialists, a ranked list of 18 efficiency factors was obtained. To select an evaluation factor that determines the effectiveness of robotization and the developed control system, a method for calculating the concordance coefficient (method of expert analysis) was applied as a measure of the consistency of a group of experts for each group of factors. An analysis of the results of the expert evaluation showed that three factors are the most significant: the degree of autonomy of work; positioning accuracy; and recognition accuracy. The generalized indicator of local autonomy of task performance was estimated based on the analysis of a set of single indicators. A system for controlling the movement of an autonomous robotic wheeled platform based on inertial and satellite navigation and calculation of the path to be overcome was developed. The developed software allows for the design of a route for the robotic platform in apple horticulture to automatically perform various technological operations, such as fertilization, growth and disease control, and fruit harvesting. With the help of the software module, the X, Y coordinates, speed and azimuth of movement were given, and the movement of the platform along the given typical turn trajectories in an intensive horticulture environment was visualized.

Wheeled Mobile Robots: State of the Art Overview and Kinematic Comparison Among Three Omnidirectional Locomotion Strategies

In the last decades, mobile robotics has become a very interesting research topic in the field of robotics, mainly because of population ageing and the recent pandemic emergency caused by Covid-19. Against this context, the paper presents an overview on wheeled mobile robot (WMR), which have a central role in nowadays scenario. In particular, the paper describes the most commonly adopted locomotion strategies, perception systems, control architectures and navigation approaches. After having analyzed the state of the art, this paper focuses on the kinematics of three omnidirectional platforms: a four mecanum wheels robot (4WD), a three omni wheel platform (3WD) and a two swerve-drive system (2SWD). Through a dimensionless approach, these three platforms are compared to understand how their mobility is affected by the wheel speed limitations that are present in every practical application. This original comparison has not been already presented by the literature and it can be used to improve our understanding of the kinematics of these mobile robots and to guide the selection of the most appropriate locomotion system according to the specific application.

Side-To-Side Difference in Electromyographic Activity of Abdominal Muscles during Asymmetric Exercises.

A side-to-side difference in the muscle size of the rectus abdominis has been suggested to increase the strain injury risk. Attenuating the difference in size of the rectus abdominis may decrease the injury risk. To explore ways to highly activate one side of the rectus abdominis, we aimed to clarify the activity levels of both sides of the muscle during asymmetric abdominal exercises. Fifteen male sprinters performed the following five asymmetric exercises for the right and left sides: (i) sit-up twist, (ii) oblique leg raise, (iii) side bridge, (iv) side bridge roll out with the elbow, and (v) side bridge roll out with the foot. Side bridge roll out with the elbow and that with the foot were performed using a wheeled platform. During the exercises, electromyographic signals were recorded bilaterally from the upper, central, and lower portions of the rectus abdominis. We calculated the root mean square of electromyograms during the concentric and eccentric phases of the exercises and normalized to that during maximal voluntary contractions. In all portions of the rectus abdominis, the root mean squares of electromyograms were significantly higher in the moving side than in the non-moving side during the concentric and eccentric phases of the side bridge, the side bridge roll out with the elbow and that with the foot (all p < 0.01), but not in sit-up twist or oblique leg raise. The root mean squares of electromyograms of all portions of the rectus abdominis in the moving side were significantly higher in the side bridge roll out with the elbow and that with the foot than in the side bridge during both phases (all p < 0.01). The results suggest that the application of the wheeled platform to side bridge is useful to highly activate one side of the rectus abdominis.

ОЦІНКА ТЯГОВО-ДИНАМІЧНИХ ПОКАЗНИКІВ КОЛІСНИХ БРОНЕТРАНСПОРТЕРІВ

The formation of reasonable requirements for advanced models of weapons and military equipment is an urgent task that must be solved on the basis of the results of scientific research. One of these tasks is the formation of operational and tactical requirements for an armored wheeled platform, which in the future should become the basis for creating a line of armored vehicles for various purposes. One of the main indicators that affect the combat and technical characteristics of such a platform is its cross-country ability. And they, in turn, depend on the design features of the machine body, transmission and its chassis. Consequently, the evaluation of the cross-country performance and the influence of the design features of the vehicle and its elements on them is a task that needs to be addressed in the course of creating a combat vehicle. After analyzing the factors affecting the maneuverability of combat vehicles, it was concluded that it is necessary to conduct a preliminary assessment of the traction and dynamic performance of promising models of armored personnel carriers in order to make an informed decision on choosing one or another armored personnel carrier as a base vehicle or conducting experimental tests. Thus, the article defines the indicators of traction-speed properties, which are the most applicable and sufficient for a comparative assessment of armored personnel carriers, as well as a comparative analysis of these indicators of armored personnel carriers BTR-4E and BTR-3DA. For comparative analysis, a test traction calculation was applied. The results of such a calculation can be used to make an informed decision on the choice of one or another armored personnel carrier as the base vehicle, as well as in the further development of proposals for the formation of reasonable requirements for the components of advanced armored personnel carriers. Keywords: the reserved wheeled platform, armament and military technique, armored personnel carriers, operational and tactical requirements, hauling-dynamic indexes.

Weighted octree-based 3D indoor pathfinding for multiple locomotion types

Accurate 3D pathfinding for multiple locomotion types is crucial for indoor applications. Many of the existing methods rely on the correct topology or the rich semantics of the indoor space, which restricts their usage in unstructured and semantic-less environments. Though space-decomposition methods, such as voxelization, have been applied to support 3D pathfinding, two major defects remain: the first is that voxelization of a coarse resolution brings about discretization artifacts, which is detrimental to the accessibility of wheeled platforms. The second is that the movement behaviors of different locomotion types were not modeled and integrated with a consistent world representation. This paper employs the octree to reconstruct the indoor spaces in multiresolution, especially to differentiate between slopes and steps. A height-related spatial weighting is proposed for modeling the 3D movement cost. The behaviors of typical locomotion types are modeled by the variable-length search in continuous coordinate space and compose a unified hybrid A* pathfinding algorithm. Experiments show this method is robust and can be applied to both structured and unstructured building models. The results are accurate 3D paths conforming to the movement behaviors of multiple locomotion types.

Design and locomotion analysis of a close-chain leg-wheel mobile platform

PurposeTo take the advantages of terrain-adaptive capability of legged platform and fast-moving ability of wheeled platform, this paper aims to design a leg-wheel mobile platform for obstacle surmounting and analyze the feasibility and locomotivity of different moving modes.Design/methodology/approachThe platform consists of six leg-wheel units. Each of the units has a close-chain mechanical leg and an actuated wheel at the end of the leg. The platform moves with two modes: legged mode and leg-wheel composite mode. The legged mode achieves high mobility driven by crank motors, while the leg-wheel composite mode achieves obstacle-surmounting ability actuated by crank motors and pitch link motors and obtains high efficiency with the hub motors. The gait planning in different modes has been carried out and the obstacle-surmounting capacity has been analyzed.FindingsBased on the results of kinematic analysis and gait planning of the close-chain leg-wheel platform, the high mobility and efficiency obstacle-surmounting ability are demonstrated with the two movement modes. The feasibility of the design and the performance of the mobile platform is verified with the prototype experiment. The results of this paper show that the platform possesses good obstacle-surmounting capability.Originality/valueThe work presented in this paper is a novel exploration to design a close-chain leg mechanism and with an actuated wheel in series. The close-chain leg mechanism has the advantages of high leg lift and single degree of freedom characteristics, which makes the platform obtain the ability of obstacle-surmounting.

REINFORCEMENT LEARNING FOR AUTONOMOUS 3D DATA RETRIEVAL USING A MOBILE ROBOT

Abstract. 3D data retrieval is required in various fields such as an industrial monitoring, agriculture, and robotics. Recent advances in photogrammetry and computer vision allowed to perform 3D reconstruction using a set of images captured with uncalibrated camera. Such technique is commonly known as Structure-from-Motion. In this paper, we propose a reinforcement learning framework RL3D for online strong camera configuration planning onboard of a mobile robot. The mobile robot consists of a skid-steered wheeled platform, a single-board computer and an industrial camera. Our aim is developing a model that plans a set of robot location that provide a strong camera configuration. We developed an environment simulator to train our RL3D framework. The simulator was implemented using a 3D model of the indoor scene and includes a model of robot’s dynamics. We trained our framework using the simulator and evaluated it using a virtual and real environments. The results of the evaluation are encouraging and demonstrate that the controller model successfully learns simple camera configurations such as a circle around an object.

COMPUTER SIMULATIONS OF CONTROLLABILITY PROCESSES FOR ROBOTIC WHEELED PLATFORMS TAKING INTO ACCOUNT RESTRICTIONS OF JERK MOTIONS

The computer simulations are considered as the required tool to design the suitable autonomous control systems optimal in different senses and especially in providing the restrictions of the jerk motions for the robotic wheeled platforms. The subject matter of this research is the development of the theory and methods for computer simulations of the controllability processes of the robotic wheeled platforms. The goal of this research is to consider the jerks of the wheeled platforms, and the jerks are reduced to the limitation of the acceleration time derivative of the mass center of the wheeled platform, so that this derivative is considered as the quantitative estimation of the jerks. The incorrectness in the Hadamard's sense for direct defining the jerks by differentiations of the phase coordinates in the case of computer simulations using the numerical methods is discussed. Tasks of this research are in developing the generalized approaches for mathematical modelling and computer simulations and in theoretical receiving of the properties inherent for the wheeled platforms and suitable for verification the computer simulations results, as well as in making the calculations to have the quantitative results about the controllability processes for the particular case of the electromechanical four-wheeled platform under the straight motion with the mode of speeding-up from the state of the rest. Methods of this research are based on the Lagrange's equations of second kind, as well as on the electromechanical analogies, and on final representing the mathematical models in the form of the system of the first ordered ordinary differential equations with the initial conditions for further numerical solving. The computer simulations are accomplished by using the Scilab free open source software. Results of this research are in the proposed suitable way for computing the jerks by the phase coordinates without its differentiations allow excluding the incorrectness in the Hadamard's sense, as well as in representing the controllability processes for the electromechanical wheeled platform, including the results for the velocities, the accelerations and the jerks which are necessary to illustrate the controllability processes for the robotic wheeled platforms. By comparison with the theoretically established inherent properties of the wheeled platforms it is shown the correctness of the results of the computer simulations. Conclusions about this research are that the developed approaches for computer simulations of the controllability processes for the robotic wheeled platforms allow considering influence of the control on the different characteristics including the velocity, the acceleration, as well as the jerk motions which are required for designing the controls optimal in different senses.

Mathematical model and motion analysis of a wheeled vibro-impact locomotion system

The paper is aimed at investigating the motion conditions of the wheeled vibro-impact locomotion system equipped with the twin crank-slider excitation mechanism and the additional braking mechanisms allowing only one-way rotation of the wheels. The novelty of the present research consists in the improved mathematical model describing the motion conditions of the vibro-impact system and the proposed parameters optimization technique that allows for maximizing the average translational velocity of the wheeled platform. The main idea of this technique is to provide the maximal velocities of internal bodies when they get in contact with the corresponding impact plates. The numerical modeling results describing the dynamic behavior of the vibro-impact system are obtained in Mathematica software and substantiate the correctness of the developed mathematical model and of the proposed parameters optimization technique. The paper can be of significant practical and scientific interest for researchers and engineers studying and improving the vibratory locomotion systems, e.g., for inspecting and cleaning the pipelines.

The Need for and Feasibility of Alternative Ground Robots to Traverse Sandy and Rocky Extraterrestrial Terrain

Robotic spacecrafts have helped expand the reach for many planetary exploration missions. Most ground mobile planetary exploration robots use wheeled or modified wheeled platforms. Although extraordinarily successful at completing intended mission goals, because of the limitations of wheeled locomotion, they have been largely limited to benign, solid terrain and avoided extreme terrain with loose soil/sand and large rocks. Unfortunately, such challenging terrain is often scientifically interesting for planetary geology. Although many animals traverse such terrain at ease, robots have not matched their performance and robustness. This is in major part due to a lack of fundamental understanding of how effective locomotion can be generated from controlled interaction with complex terrain on the same level of flight aerodynamics and underwater vehicle hydrodynamics. Early fundamental understanding of legged and limbless locomotor–ground interaction has already enabled stable and efficient bioinspired robot locomotion on relatively flat ground with small obstacles. Recent progress in the new field of terradynamics of locomotor–terrain interaction begins to reveal the principles of bioinspired locomotion on loose soil/sand and over large obstacles. Multilegged and limbless platforms using terradynamics insights hold the promise for serving as robust alternative platforms for traversing extreme extraterrestrial terrain and expanding the reach in planetary exploration.