A dielectric elastomer-based morphing aerodynamic surface for a mars rover

Abstract

This invention discloses a deformable, tumbleweed-inspired Mars exploration robot based on dielectric elastomers, belonging to the field of exoplanet exploration technology, and solving the problems of large size and heavy weight of tumbleweed robots. The invention includes a spherical frame, a flexible solar panel sail, several dielectric elastomer actuators, and a central spherical cabin. The flexible solar panel sail is disposed inside and connected to the spherical frame, with the central cabin located at its center. Several dielectric elastomer actuators are embedded inside the flexible solar panel sail; one end of each actuator is connected to the central cabin, and the other end is connected to the spherical frame. This invention achieves speed control by adjusting its windward area to regulate wind power utilization. Using dielectric elastomers as actuators, it achieves volume change while maintaining a lightweight and compact structure with enhanced terrain adaptability.

Description

Technical Field

[0001] This invention relates to the field of extraterrestrial planet exploration technology, specifically to a deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer. Background Technology

[0002] Exploration of exoplanets is a crucial component of humankind's exploration of the universe. Mars, hailed as a "new continent," holds irreplaceable strategic significance for revealing the evolutionary patterns of the solar system, assessing the possibility of extraterrestrial life, and laying the foundation for future manned landings and interstellar migration. However, the Martian surface presents extreme conditions such as strong near-Earth winds and rugged terrain (spotted with impact craters and canyons), placing stringent demands on surface exploration equipment. Existing exploration methods still have many shortcomings.

[0003] Current Mars surface exploration primarily relies on two types of equipment: orbiters and landers / rover. Orbiters (such as the US Mars Reconnaissance Orbiter and my country's Tianwen-1 orbiter) can achieve global remote sensing observation of Mars, but due to limitations in orbital altitude and exploration methods, they cannot obtain data on the surface microenvironment or close-range geological samples. Landers / rover are mainly wheeled rovers, with typical examples including the US Curiosity and Perseverance rovers and my country's Zhurong rover. These devices carry high-precision scientific payloads (such as rock analyzers and radiation detectors) and can conduct detailed exploration in specific areas. However, wheeled rovers have problems such as poor terrain adaptability, slow speed, and high cost. Although the technology is mature, it is necessary to develop a new exoplanet surface exploration scheme to achieve large-scale exoplanet surface exploration.

[0004] To overcome the limitations of wheeled rovers, research institutions have proposed the concept of tumbleweed-type exploration robots. These robots mimic the morphology of tumbleweed plants on Earth, employing a spherical or near-spherical structure and utilizing Martian winds for passive or semi-active movement. They offer advantages such as low cost, strong obstacle-crossing ability, and wide coverage. Currently, publicly available tumbleweed robot designs primarily utilize inflatable structures. Inflating the robot increases its volume, thereby increasing its utilization of wind power and enabling passive rolling. However, these robots often reach dimensions of tens of meters and weigh over 20 kg, making them highly unsuitable for spacecraft transport.

[0005] In summary, the tumbleweed-inspired exploration robot design is a feasible solution for exploring the surface of extraterrestrial planets, addressing the shortcomings of wheeled rover solutions. However, existing tumbleweed robot designs have certain limitations, making the development of a novel tumbleweed robot of significant importance. Summary of the Invention

[0006] To address the aforementioned issues of large size and heavy weight in existing tumbleweed robots, this invention proposes a deformable tumbleweed-inspired Mars exploration robot based on a dielectric elastomer. This invention achieves speed control by adjusting its windward surface area to optimize wind utilization. Using a dielectric elastomer as the actuator, it achieves volume variation while maintaining a lightweight and compact structure with enhanced terrain adaptability.

[0007] This invention proposes a deformable, tumbleweed-inspired Mars exploration robot based on dielectric elastomers, which specifically includes a spherical frame, a flexible solar panel sail, several dielectric elastomer actuators, and a spherical core cabin. The flexible solar panel sail is disposed inside the spherical frame, with the spherical core cabin located at its center. Several dielectric elastomer actuators are embedded inside the flexible solar panel sail. One end of each dielectric elastomer actuator is connected to the spherical core cabin, and the other end is connected to the spherical frame.

[0008] Furthermore, the spherical frame and the dielectric elastomer actuator are connected by a tension spring.

[0009] Furthermore, the spherical frame includes several spokes, each spoke having a semi-circular ring structure, with the ends of several spokes hinged together; torsion springs are provided between each pair of spokes.

[0010] Furthermore, the spokes are made of aluminum-based silicon carbide composite material.

[0011] Furthermore, the flexible solar panel sail is spherical.

[0012] Furthermore, the flexible solar panel sail includes several sails and several flexible solar panels. The sails have a fan-shaped structure, and the several sails are connected to each other with their centers overlapping. The flexible solar panels are disposed on the surface of the sails.

[0013] Furthermore, the sail includes sail one and sail two. The plane of sail one after it is unfolded is in the same plane as the line connecting the hinge points at both ends of the spokes. Sail two is a folded structure and is perpendicular to the plane of sail one after it is unfolded.

[0014] Furthermore, the dielectric elastomer actuator is positioned at the sail connection location.

[0015] Furthermore, the dielectric elastomer actuator has a strain of 150% and a radiation-resistant coating on its surface.

[0016] Furthermore, a controllable voltage source and a microcontroller are installed inside the spherical core cabin; the controllable voltage source and the dielectric elastomer actuator are electrically connected; the microcontroller, the controllable voltage source, and the flexible solar panel sail signal are connected.

[0017] The beneficial effects of the deformable tumbleweed-inspired Mars exploration robot based on a dielectric elastomer described in this invention are as follows:

[0018] (1) The deformable tumbleweed-like Mars exploration robot based on dielectric elastomer described in this invention forms a foldable frame + lightweight actuator design through a spherical frame structure and dielectric elastomer actuator. The storage space is less than 1 / 50 of that of traditional tumbleweed robots, and the total weight is less than 0.2 kg but can carry a 1 kg load, supporting batch loading and multi-device exploration.

[0019] (2) The deformable tumbleweed Mars exploration robot based on dielectric elastomer described in this invention controls the degree of deployment of flexible solar panel sails by dielectric elastomer actuators, adjusts the windward area of ​​flexible solar panel sails to adapt to wind speed, and achieves the purpose of active speed control; when moving in low wind speed areas, the robot's center of gravity is adjusted by the cooperation of several dielectric elastomer actuators to achieve autonomous movement. This mode is compatible with more than 90% of Martian surface scenes.

[0020] (3) The deformable tumbleweed Mars exploration robot based on dielectric elastomer described in this invention is driven by wind power obtained by flexible solar panel sails. Only the deformation of the flexible solar panel sails consumes a small amount of electrical energy. The flexible solar panel replenishes the consumed electrical energy in real time, and can conduct autonomous exploration for several months or even several years, realizing efficient energy utilization and long-term exploration.

[0021] (4) The deformable tumbleweed Mars exploration robot based on dielectric elastomer described in this invention has a spherical frame structure made of aluminum-based silicon carbide composite material, which is resistant to high and low temperatures and impacts; the spherical core is sealed as a whole, thus effectively isolating sand and dust; the surface of the dielectric elastomer actuator is coated with a radiation-resistant coating to prevent performance degradation; the robot has a reliable overall structure and is adaptable to the harsh environment of extraterrestrial planets. Attached Figure Description

[0022] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] In the attached diagram:

[0024] Figure 1 This is a schematic diagram of the deployed state structure of a deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer, as described in this invention.

[0025] Figure 2 This is a schematic diagram of the folded-up structure of a deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer, as described in this invention.

[0026] Figure 3 This is a schematic diagram of the autonomous motion mode of a deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer, as described in this invention.

[0027] Among them: 1-tension spring, 2-flexible solar panel sail, 3-spoke, 4-dielectric elastomer actuator, 5-ball core, 6-torsion spring. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other. The described embodiments are merely some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] Specific implementation method one: See Figures 1-3 This embodiment describes a deformable, tumbleweed-inspired Mars exploration robot based on dielectric elastomers. Specifically, it includes a spherical frame, a flexible solar panel sail 2, six dielectric elastomer actuators 4, and a central chamber 6. The flexible solar panel sail 2 is housed within the spherical frame but not directly connected to it. The central chamber 6 is located at the center of the flexible solar panel sail 2. Several dielectric elastomer actuators 4 are embedded within the flexible solar panel sail 2. One end of each actuator 4 is connected to the central chamber 6, and the other end is connected to the spherical frame via a tension spring 1. When fully deployed, the robot is designed as a sphere with a radius of 250 mm. The effective windward area can be considered as a circle with a radius of 200 mm-500 mm. This means the material strain of the dielectric elastomer actuators 4 is 150%, balancing mobility in the low-density Martian atmosphere with relatively low mass and volume. The total weight of the exploration robot is kept to within 0.2 kg, and it can carry a payload of about 1 kg, enabling the exploration robot to be portable, deployed on a large scale, and have a large effective payload in Mars exploration.

[0030] The spherical frame includes twelve spokes 3, each spoke in a semi-circular ring structure, with hinged ends. A torsion spring 6 is installed between each pair of hinged spokes 3, with a natural angle of 30°. When the spherical frame is unfolded, the included angle between any two adjacent spokes 3 is 30°. Figure 1 As shown; when collapsed Figure 2As shown, the spokes 3 compress the torsion spring 6, which is in a compressed state. The spokes 3 are stacked together to reduce the space they occupy. Furthermore, the probe robot can be folded up during transport, significantly reducing its space requirements and facilitating its mounting on the Mars rover. Upon arrival on the Martian surface, it is released from the spacecraft and unsecured. The torsion spring 6 returns to its original angle, and the probe robot quickly unfolds into a spherical structure, providing stable support for the entire probe robot. This allows it to roll or move smoothly across the complex terrain of Mars, such as dunes and rocky areas, while also protecting other internal components from direct damage from the harsh Martian environment. The spokes 3 are made of aluminum-based silicon carbide composite material.

[0031] The flexible solar panel sail 2 unfolds into a spherical shape. The flexible solar panel sail 2 comprises twelve sails and twenty-four flexible solar panels. The sails are quarter-circular fan-shaped structures, with the twelve fan-shaped sails interconnected at their straight edges and their centers coinciding. Figure 1 As shown; the sail includes sail one and sail two. The plane of sail one after it is unfolded is in the same plane as the line connecting the hinge points at both ends of the spokes 3. Sail two is a folded structure and is perpendicular to the plane of sail one after it is unfolded. Sail two is at a certain angle to the line connecting the hinge points at both ends of the spokes 3. In this embodiment, the line connecting sail two and the hinge points at both ends of the spokes 3 is perpendicular.

[0032] The dielectric elastomer actuator 4 is located at the sail connection point; the flexible solar panel is mounted on the sail surface, serving both as a power assist and energy harvesting function. When the dielectric elastomer actuator 4 extends, the flexible solar panel sail 2 unfolds, using the wind force on the Martian surface to propel the robot across the Martian surface, simulating the characteristics of tumbleweeds rolling in the wind, achieving large-scale exploration coverage with low energy consumption, while simultaneously supplementing power through the flexible solar panel.

[0033] The dielectric elastomer actuator 4 is the core driving component for the robot's deformation and movement. When a voltage is applied to the two ends of the dielectric elastomer actuator 4, it deforms due to electrostatic effects; after the voltage is removed, it returns to its original shape. Using this dielectric elastomer actuator 4 connected to the flexible solar panel sail 2, when the actuator 4 is not energized, the spring pulls the dielectric elastomer, and the sail is in an unfolded state, maximizing wind-receiving area and wind power utilization, enabling rapid movement. When a voltage is applied to the two ends of the dielectric elastomer actuator 4, it contracts, the flexible solar panel sail 2 retracts, the wind-receiving area decreases, wind power utilization decreases, and movement speed decreases. The surface of the dielectric elastomer actuator 4 is coated with a radiation-resistant coating to prevent performance degradation.

[0034] The spherical core 6 houses a controller and sensors. The controller includes a controllable voltage source and a microcontroller. The controllable voltage source is electrically connected to the dielectric elastomer actuator 4, applying voltage to control its length change. The microcontroller is signal-connected to the controllable voltage source and the flexible solar panel sail 2. The microcontroller receives information from various sensors and ground commands, analyzes and processes the commands and sensor information, and sends commands to the controllable voltage source, flexible solar panel sail 2, and other components to coordinate the work of each part to complete the command task. The exploration robot moves or remains stationary according to the received task commands. Combining the wind speed data detected by the sensors, the controllable voltage source outputs a signal to the dielectric elastomer actuator 4, causing it to deform and change the unfolded area of ​​the flexible solar panel sail 2, thereby controlling the movement speed or reducing the area until the wind is insufficient to move the robot, thus achieving controllable robot movement.

[0035] The sensor module can be equipped with different types of sensors depending on the mission requirements, including a terrain sensor, which can detect the topographic relief and obstacle distribution on the Martian surface; an atmospheric sensor, which can monitor parameters such as the composition, pressure, and temperature of the Martian atmosphere; and a wind speed sensor, which monitors the wind speed data at the current location.

[0036] When wind speeds are low but movement is still required, the robot can change the length of the dielectric elastomer actuator 4 in a specific direction, thereby altering its center of gravity. By sequentially changing the center of gravity, it can achieve autonomous movement. For example... Figure 3 As shown, the lengths of each dielectric elastomer actuator 4 are changed sequentially during rolling to keep the center of gravity in the direction of robot movement, so that the robot can continuously roll.

[0037] The specific working process of the deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer described in this embodiment is as follows:

[0038] (a) Ground preparation stage: pre-installation, debugging and storage

[0039] 1. Component assembly: Assemble 12 aluminum-based silicon carbide spokes 3 and install torsion springs 6, connect dielectric elastomer actuators 4 to flexible solar panel sails 2, integrate the spherical core 5 (including a controllable voltage source, microcontroller, and sensor) and complete the circuit connection.

[0040] 2. Functional debugging: In the simulated Mars environment cabin, test the deformation accuracy (strain 150%), wind speed and control speed logic matching (response < 0.5 s), and autonomous rolling direction deviation (< 5°) of the dielectric elastomer actuator 4.

[0041] 3. Folding and Storage: Compression of the spokes 3 causes deformation of the torsion spring 6, and the flexible solar panel sail 2 folds along with the frame (e.g., Figure 2 As shown in the figure, it is loaded into the spacecraft's storage compartment.

[0042] (II) Mars Deployment Phase: Landing and Deployment

[0043] 1. Batch Deployment: After the Mars probe reaches its orbit, the launch capsule will be ejected to the preset exploration area, and the hatch will automatically unlock after landing.

[0044] 2. Frame Deployment: The fixing device is released, and the torsion spring 6 returns to its original position, causing the spokes 3 to unfold into a spherical shape (e.g., Figure 1 As shown), the tension spring 1 pulls the dielectric elastomer actuator 4 to unfold the flexible solar panel sail 2, and the solar panel charging initialization is completed.

[0045] 3. Communication Establishment: The core module 5 establishes a connection with the orbiter, sends deployment signals and initial data to the ground, and awaits exploration commands.

[0046] (III) Surface Exploration Phase:

[0047] 1. Active speed control detection mode (wind speed ≥ 2 m / s)

[0048] The wind speed sensor transmits data every 10 seconds. The microcontroller combines the ground commands (direction, speed) to calculate the windward area and controls the controllable voltage source to drive the dielectric elastomer actuator 4 to deform and adjust the unfolded area of ​​the flexible solar panel sail 2.

[0049] The flexible solar panel sail 2 uses wind power to propel the robot to roll, terrain sensors avoid obstacles, and atmospheric sensors collect data, which is uploaded every 5 minutes; when it needs to be stationary, the flexible solar panel sail 2 is reduced in size until it can no longer be propelled by the wind.

[0050] 2. Autonomous motion detection mode (wind speed < 2 m / s)

[0051] After the wind speed sensor detects low wind speed, the microcontroller switches modes and notifies the ground, which then cyclically adjusts the length of the dielectric elastomer actuator 4 in different orientations according to directional commands, so that the center of gravity falls in front of the direction of movement (e.g., ...). Figure 3 (as shown)

[0052] The robot rolls continuously under gravity, and its speed is controlled by the extension frequency of the dielectric elastomer actuator 4 (maximum 0.2 m / s). When there is insufficient light, the frequency is reduced to reduce energy consumption, and the extension frequency is increased after the light is restored.

[0053] (iv) Task completion phase: data backhaul and hibernation

[0054] 1. When the task is completed or energy is less than 10%, the microcontroller controls the flexible solar panel sail 2 to retract, and the frame maintains a spherical shape to reduce sand and dust accumulation.

[0055] 2. Turn off unnecessary sensors, retain communication and wake-up circuits, upload all data and then go into hibernation, waiting for ground wake-up command.

[0056] In summary, the deformable tumbleweed-inspired Mars exploration robot based on dielectric elastomer described in this invention forms a foldable frame + lightweight actuator design through a spherical frame structure and dielectric elastomer actuator 4. The storage space is less than 1 / 50 of that of traditional tumbleweed robots, and the total weight is less than 0.2 kg, yet it can carry a 1 kg payload, supporting batch deployment and multi-device exploration.

[0057] The present invention discloses a deformable, wind-mimicking tumbleweed Mars exploration robot based on dielectric elastomers. The flexible solar panel sail 2 is deployed by a dielectric elastomer actuator 4, which adjusts the windward area of ​​the flexible solar panel sail 2 to adapt to the wind speed and achieve active speed control. When moving in low wind speed areas, the robot's center of gravity is adjusted by the cooperation of several dielectric elastomer actuators 4 to achieve autonomous movement. This mode is compatible with more than 90% of Martian surface scenarios.

[0058] The present invention describes a deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer. It is driven by wind power obtained through a flexible solar panel sail 2, with only the deformation of the flexible solar panel sail 2 consuming a small amount of electrical energy. The flexible solar panel replenishes the consumed electrical energy in real time, enabling continuous autonomous exploration for months or even years, achieving energy-efficient utilization and long-term exploration.

[0059] The present invention discloses a deformable tumbleweed-inspired Mars exploration robot based on dielectric elastomers. The spherical frame structure is made of aluminum-based silicon carbide composite material, which is resistant to high and low temperatures and impacts. The spherical core chamber 5 is completely sealed, thereby effectively isolating sand and dust. The surface of the dielectric elastomer actuator 4 is coated with a radiation-resistant coating to prevent performance degradation. The robot has a reliable overall structure and is adaptable to the harsh environment of exoplanets.

[0060] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the invention. They can also be reasonable combinations of the features described in the above embodiments. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer, characterized in that: It includes a spherical frame, a flexible solar panel sail (2), several dielectric elastomer actuators (4), and a spherical core chamber (6); the flexible solar panel sail (2) is located inside the spherical frame, and a spherical core chamber (6) is located at its center; several dielectric elastomer actuators (4) are embedded inside the flexible solar panel sail (2); one end of the dielectric elastomer actuator (4) is connected to the spherical core chamber (6), and the other end is connected to the spherical frame; The spherical frame and the dielectric elastomer actuator (4) are connected by a tension spring (1); The spherical frame includes several spokes (3), each spoke (3) having a semi-circular ring structure, with the ends of the spokes (3) hinged together; torsion springs are provided between each pair of spokes (3); The flexible solar panel sail (2) is spherical; The flexible solar panel sail (2) includes several sails and several flexible solar panels. The sails are fan-shaped structures, and the several sails are connected to each other with their centers overlapping. The flexible solar panels are disposed on the surface of the sails. The sail includes sail one and sail two. The plane of sail one after it is unfolded is in the same plane as the line connecting the hinge points at both ends of the spokes (3). Sail two is a folded structure and is perpendicular to the plane of sail one after it is unfolded. The dielectric elastomer actuator (4) is located at the connection point of the sails; When the wind speed is very low but movement is required, the robot can change the length of the dielectric elastomer actuator (4) in a specific direction, thereby changing the position of the robot's center of gravity. By changing the center of gravity in sequence, the robot can achieve an autonomous movement mode.

2. The deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer according to claim 1, characterized in that: The spokes (3) are made of aluminum-based silicon carbide composite material.

3. The deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer according to claim 1, characterized in that: The dielectric elastomer actuator (4) has a strain of 150% and a radiation-resistant coating on its surface.

4. The deformable, tumbleweed-inspired Mars exploration robot based on a dielectric elastomer according to claim 1, characterized in that: The sphere core (6) is equipped with a controllable voltage source and a microcontroller; the controllable voltage source and the dielectric elastomer actuator (4) are electrically connected; the microcontroller, the controllable voltage source, and the flexible solar panel sail (2) are signal connected.

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