Omnidirectional carrier with passive rotational joints

Abstract

An omni-directionally orientable vehicle includes a body portion, an arm extending radially from the body portion, and an orientable propulsion module. Each propulsion module is coupled with the arm and includes at least three propulsion units rigidly attached to the propulsion module. Each propulsion module is coupled to the arm by insertion of a rotational connection formed by a first rotational joint attached to the arm and a second rotational joint attached to the propulsion module and vertically coupled with the first rotational joint. The first rotational joint allows the propulsion module to rotate about the arm and the second rotational joint allows the propulsion module to rotate about an axis perpendicular to the arm, thereby providing the propulsion module with two DOF relative to the body portion. The vehicle includes a rotary encoder located proximate the rotational joint and configured to monitor an orientation of the propulsion module relative to the body portion.

Description

Technical Field

[0001] The present invention relates to the field of omnidirectional vehicles. Such vehicles are capable of independently applying forces and torques in three-dimensional space, thereby achieving full drive over their entire configuration space. In particular, the omnidirectional vehicle disclosed herein incorporates two orthogonal passive rotation joints between its main body and its orientable propulsion module, and can be applied, for example, to aerial, underwater and space manipulation and operation. Background Art

[0002] To fully describe the motion of a rigid body in three-dimensional space, at least six variables are required. A common convention is to use three continuous rotations along the Z axis (yaw), Y axis (pitch), and X axis (roll) to represent orientation, and three translation variables X, Y, and Z to represent position. Therefore, a rigid body in three-dimensional space is considered to have six independent degrees of freedom (DOF).

[0003] Parallel-axis multirotors (such as quadrotors, hexacopters, etc.) are underactuated aerial vehicles. That is, they cannot simultaneously control 6 DOF of their main body. In such devices, controlled horizontal translation requires sacrificing angular control, and vice versa.

[0004] Recently, Unmanned Aerial Vehicles (UAVs) have been successfully applied to tasks such as search and rescue operations, traffic monitoring, infrastructure inspection, agriculture, or filming. While most of these tasks rely solely on the passive sensing capabilities of the vehicle, recent advances in the field of aerial robotics seek to enable active physical interaction of the vehicle with its environment, thus extending the scope of this technology to activities such as aerial work, remote infrastructure maintenance, or pick and place operations.

[0005] These types of aerial manipulation applications usually require the attachment of tools to the vehicle. Underactuated vehicles present the disadvantage of not being able to control both their position and orientation. One way to overcome this lack of maneuverability is to attach an actuation mechanism such as a gimbal or a robotic arm to the main body of the underactuated vehicle. However, this solution increases the vehicle weight, reduces the total payload and autonomy, and also has a high control complexity due to the coupled dynamics of both subsystems.

[0006] Another possible solution is to rigidly attach the manipulation tool to the main body of the fully actuated vehicle. Fully actuated vehicles independently control their position and orientation, which results in high maneuverability for tool manipulation tasks. One type of fully actuated aerial vehicle that has received particular attention is the omnidirectional vehicle. These systems meet the fully actuated condition over their entire orientation space and are not limited to a specific range. Many omnidirectional vehicles rely on dedicated actuators (e.g., servomotors) to tilt their thrusters and control the orientation of the net thrust vector relative to the main body, however, these additional actuators add to the complexity of the structure, increase weight, make manufacturing and maintenance costs higher, and reduce vehicle safety and reliability.

[0007] Therefore, there is a need in the art for omnidirectional fully-driven vehicles with a simple structure and reduced cost, while also exhibiting high performance, high precision and high maneuverability. Summary of the invention

[0008] In order to overcome the above-mentioned shortcomings, the present invention discloses an omnidirectional vehicle based on an orientable thrust generating mechanism, wherein the omnidirectional vehicle is formed by a plurality of orientable propulsion modules, and the plurality of orientable propulsion modules are connected to a main body (cabin) via a passive rotating connection formed by two continuous rotating joints, and the rotation axes of the two continuous rotating joints are coplanar and perpendicular.

[0009] The first object of the present invention is an omnidirectional vehicle, which includes a main body, a plurality of arms extending radially from the main body and connected thereto, and a plurality of orientable propulsion modules. Each orientable propulsion module is connected to a corresponding arm among the plurality of arms and includes at least three propulsion units. At least three propulsion units are rigidly attached to the frame of the corresponding orientable propulsion module in a fixed position and orientation. That is, the propulsion unit is rigidly attached to the frame of the corresponding orientable propulsion module at a fixed X, Y and Z position and at a fixed yaw angle, roll angle and pitch angle. The thrust applied by each of the propulsion units of a specific orientable propulsion module may be different from each other. Therefore, the plurality of propulsion units of the orientable propulsion module may be configured to achieve any desired orientation and modulus of the net thrust vector of the propulsion modulus.

[0010] Furthermore, each orientable propulsion module is connected to a corresponding arm of the plurality of arms by the insertion of a rotary connector. Each rotary connector is formed by a first passive rotary joint connected to the corresponding arm and a second passive rotary joint attached to the orientable propulsion module, wherein the rotation axis of the second rotary joint is perpendicular to the rotation axis of the first rotary joint and is coplanar with the rotation axis of the first rotary joint. The first rotary joint is configured to allow the orientable propulsion module to rotate around the arm, and the second rotary joint is configured to allow the orientable propulsion module to rotate around the rotation axis of the orientable propulsion module perpendicular to the arm, so that the orientable propulsion module is provided with two DOFs relative to the main body. In order to fully control the relative orientation of the thrust vector of each orientable propulsion module relative to the main body, no more than two DOFs are required. For example, the rotary connector can be a single body in which a continuous vertical rotary joint is integrated or formed. Alternatively, each rotary joint can be integrated or formed as a separate body positioned continuously with each other.

[0011] As used herein, the term "revolute joint", also known as a pin joint or hinge joint, may refer to a single degree of freedom kinematic pair capable of limiting the motion of two bodies to pure rotation along a common axis. A revolute joint does not allow translational or sliding linear motion. A revolute joint may be made of a pin or knuckle joint through a swivel bearing. The term "passive revolute joint" refers to a revolute joint that is not actuated by any device or mechanism, such as a motor, actuator, or the like.

[0012] In addition, the omnidirectional vehicle includes a rotary encoder located near each rotary joint, which is configured to monitor the orientation of each orientable propulsion module relative to the main body. The distance between the rotary joint and the corresponding rotary encoder will depend on the operating range of the encoder and will be small enough to allow the encoder to monitor the rotation of the corresponding rotary joint. In particular, a rotary encoder located near the first rotary joint connected to the arm monitors the angular position of the rotary joint (or the body in which the rotary joint is integrated) relative to the arm, and a rotary encoder located near the second rotary joint connected to the rotation axis of the orientable propulsion module monitors the angular position of the rotary joint (or the body in which the rotary joint is integrated) relative to the rotation axis, so that the combination of the readings of the two rotary encoders of the same rotary connection will provide the orientation of a specific orientable propulsion module relative to the main body.

[0013] As used herein, the term "rotary encoder" may refer to an electromechanical device configured to monitor the angular position or motion of a shaft or axle and convert it into an analog or digital signal. The output of the rotary encoder provides information about the current shaft position or about the motion of the shaft. The rotary encoder may be an absolute or incremental rotary encoder.

[0014] The motion of the orientable propulsion module can be controlled by changing the relative thrust generated by each propulsion unit. Specifically, the motion (roll and pitch) of the orientable propulsion module around two rotation axes can be controlled by changing the relative thrust generated by each propulsion unit. For example, roll and pitch can be achieved by increasing the thrust of the propulsion unit located on one side and reducing the thrust of the propulsion unit located on the opposite side. Horizontal motion can be achieved by tilting the orientable propulsion module in the intended direction of travel, and vertical motion can be achieved by increasing the thrust in each propulsion unit at the same time (ascending) or by reducing the thrust in each propulsion unit at the same time (descending). The angular motion of the main body is controlled by modifying the net thrust of each propulsion module. For example, roll and pitch are controlled by increasing the thrust of the propulsion module located on one side and reducing the thrust of the propulsion module located on the opposite side, while yaw can be controlled by a thrust vectoring strategy, in which each propulsion module is tilted in the direction of maximum torque.

[0015] By using passive revolute joints to couple the orientable propulsion module to the body of the omnidirectional vehicle, the rotation axis (particularly the rotation axis coupled to the orientable propulsion module and the arm of the body also acting as the rotation axis) can be passed through the corresponding revolute connection without including any space in the body or bodies forming or integrating the revolute joints for devices such as inertial sensors (gyroscopes, accelerometers, magnetometers, etc.) to measure the orientation of the orientable propulsion module relative to the body. Instead, the orientation can be measured with an external device (such as a rotary encoder), thereby reducing the complexity of the structure of the revolute connection and reducing its maintenance and manufacturing costs.

[0016] The measurement of the orientation of the orientable propulsion module relative to the main body, and the measurement of the orientation of the omnidirectional vehicle itself, obtained using a rotary encoder, is more accurate than the orientation obtained by using an estimation algorithm calculated based on measurements from inertial sensors. In addition, it requires less on-board calculations because the rotary encoder provides the angle between the orientable propulsion module and the main body as a relative measurement, rather than deriving an estimate from a complex sensor fusion algorithm. The use of a rotary encoder further avoids drift problems that may occur with inertial sensors.

[0017] In some embodiments, not as part of the present invention, the omnidirectional vehicle may have some rotating connections that have only one revolute joint, so the corresponding orientable propulsion modules have only one DOF. Preferably, in these embodiments, the remaining orientable propulsion modules will have sufficient DOF, so the omnidirectional vehicle is overactuated. In some other embodiments, not as part of the present invention, some orientable propulsion modules may be fixedly coupled to their respective arms. Preferably, in these embodiments, the remaining orientable propulsion modules will have sufficient DOF, so the omnidirectional vehicle is also overactuated.

[0018] In some embodiments, each rotating connector includes a body having a first aperture and a second aperture, through which the corresponding arm is inserted and about which the rotating connector rotates, and a second aperture perpendicular to the first aperture, through which a rotating shaft connected to the corresponding orientable propulsion module is inserted and rotated. The rotating shaft may be an integral part of the orientable propulsion module, or may be part of the rotating connector itself and connected to the orientable propulsion module.

[0019] In some embodiments, when the orientation measurement of the orientable propulsion module relative to the main body needs to be more accurate (for example, when the omnidirectional vehicle is to perform high-precision operations), an inertial measurement unit (IMU) (e.g., a gyroscope, accelerometer, magnetometer, or any combination thereof) can be placed in the main body to combine the absolute angle measurement obtained by the rotary encoder with the angular velocity measurement obtained by the IMU.

[0020] In some embodiments, the first and second apertures of the body of the rotating connector include corresponding rotating bearings or friction bushings with a low friction coefficient coupled to their inner surfaces, so that the corresponding arms and the rotating shaft rotate relative to the body through the rotating bearings. In some other embodiments, the bearings or bushings can be an integral part of the body.

[0021] In some embodiments, each propulsion unit is an independently controllable propulsion unit and is configured to generate an independent thrust modulus. Preferably, each propulsion unit is configured to generate a torque that can be dependent on or independent of the thrust modulus generated. The thrust modulus generated by each propulsion unit should be independently controllable. Thus, the varying thrust (and possibly torque) of the different propulsion units directs the propulsion module without the need for dedicated actuators at the joints.

[0022] In some embodiments, the center of rotation of the propulsion module is located on the geometric axis of the main body and on the plane defined by the geometric axis of the frame of the propulsion module. This allows avoiding collisions between the orientable propulsion module and the main body of the omnidirectional vehicle in every possible configuration.

[0023] In some embodiments, the propulsion unit can be any device or system capable of providing propulsion or driving force. More particularly, the propulsion unit is selected from the group consisting of a rotor, a propeller, a turboprop engine, a jet engine, an air jet, and any combination thereof.

[0024] In some embodiments, the omnidirectional vehicle includes a landing gear or multiple landing gears attached to the lower surface of the main body, each landing gear attached to the lower surface of a corresponding orientable propulsion module. Either of these two configurations provides a stable configuration for the omnidirectional vehicle when landing.

[0025] In some embodiments, the center of mass of the orientable propulsion module is located below the center of rotation of the rotating connection so that the propulsion module remains horizontal in its static configuration.

[0026] In some embodiments, the omnidirectional orientable vehicle is selected from the group consisting of an omnidirectional aerial vehicle, an omnidirectional underwater vehicle, an omnidirectional outer space vehicle, or any combination thereof.

[0027] In some embodiments, the omnidirectional vehicle includes slip rings electrically connecting the main body and the orientable propulsion module. The slip rings are configured to allow at least one of data and power to be transmitted between the main body and the orientable propulsion module. These slip rings allow the rotary connection (and more specifically the rotary joint) to rotate infinitely.

[0028] In some embodiments, the omnidirectional vehicle includes loose cables electrically connecting the main body and the orientable propulsion module. These loose cables are combined with an automatic unwinding algorithm or a mechanical limit to limit the number of turns of the loose cables. The loose cables are configured to allow at least one of data and power to be transmitted between the main body and the orientable propulsion module. Preferably, the mechanical limit is a screw mechanism with a stop.

[0029] In some embodiments, the omnidirectional vehicle includes a controller located in the main body and configured to operate multiple orientable propulsion modules. In addition, the omnidirectional vehicle may also include a single battery or battery pack in the main body to power the orientable propulsion module and the remaining electrical and electronic components of the vehicle. Data and power can be transmitted from the main body to the orientable propulsion module via slip rings or loose cables. These embodiments are particularly advantageous for reducing costs, minimizing components that may fail, facilitating assembly of the vehicle, and reducing the inertia of the propulsion module, thereby making the system more flexible and efficient.

[0030] In some other embodiments, the omnidirectional vehicle includes a main controller and a plurality of secondary controllers, the main controller being located in the main body, and each secondary controller being located in a corresponding directional propulsion module. The plurality of secondary controllers are configured to operate the corresponding directional propulsion modules to which they are installed, and the main controller is configured to manage the plurality of secondary controllers. This example provides distributed management of the omnidirectional vehicle, wherein, in the event of failure of the controller currently responsible for managing the omnidirectional vehicle, any one of the plurality of controllers can control the entire vehicle. In addition, the omnidirectional vehicle may also include a single battery or battery pack located in the main body, and another single battery or battery pack located in at least one (preferably all) directional propulsion modules. Preferably, the battery in the main body is used to power the electrical and electronic components of the main body, and the battery in the propulsion module is used to power the electrical and electronic components of the corresponding propulsion module. However, since data and power can be transmitted from the main body to the directional propulsion module via slip rings or loose cables, and vice versa, in the event of any battery failure or battery exhaustion, power can be transmitted from the main body or any directional propulsion module to any component within the omnidirectional vehicle. While control redundancy increases the safety and reliability of the vehicle, power redundancy increases the operational autonomy of the vehicle.

[0031] In some embodiments, the omnidirectional vehicle is an overdriven omnidirectional vehicle. When the vehicle has more independent control inputs than the 6 controlled DOF of the main body (cabin), the vehicle is overdriven. Preferably, the omnidirectional vehicle can have three or more orientable propulsion modules, each propulsion module has at least three propulsion units to ensure that it is overdriven. With an overdriven omnidirectional vehicle, some parameters of vehicle operation can be optimized, such as optimizing energy consumption, reducing vibration, etc.

[0032] In some examples, the rotating connection (more specifically the revolute joint) can include a quick release system so that the orientable propulsion module can be releasably attached to the main body portion. Releasably attaching the propulsion module to the main body portion facilitates maintenance operations of the vehicle and allows for expandability of the vehicle, as a currently operating propulsion module can be easily and quickly replaced with a different propulsion module.

[0033] In some examples, a revolute connection, more specifically a revolute joint, may include a blocking mechanism configured to temporarily block the rotational motion of the revolute joint. These revolute connections with temporarily blocked DOF may be useful for cruising mode, where it is desirable to ensure that the joint maintains its position independent of external disturbances.

[0034] In some examples, the rotating connection (more specifically, the revolute joint) can include a shock absorbing mechanism configured to absorb the shock pulse generated by the movement of the propulsion module relative to the main body. These joints with shock absorbing devices can improve the stability and accuracy of the vehicle.

[0035] Preferably, the plurality of orientable propulsion modules are positioned equidistantly relative to the center point of the main body. In this way, the stability of the omnidirectional vehicle is maximized. In some other examples, the propulsion modules may be attached to the main body in different distributions depending on the purpose and specific structure of the vehicle.

[0036] A second object of the present invention is a method for manipulating an omnidirectional vehicle. The method comprises: setting an omnidirectional vehicle as described above. Preferably, the omnidirectional vehicle set up will be an overdriven omnidirectional vehicle. The method also comprises: determining the displacement of the main body of the omnidirectional vehicle in Cartesian space, determining the thrust and orientation of the omnidirectional vehicle by the controller of the omnidirectional vehicle based on the desired displacement, and determining the thrust and orientation of each of a plurality of orientable propulsion modules by the controller based on the determined thrust and orientation of the omnidirectional vehicle. Thereafter, the method comprises: adjusting the tilt angle of each of a plurality of orientable propulsion modules by means of the controller by performing a rotational movement of each orientable propulsion module relative to the main body via a rotating connection, wherein the relative rotational movement is based on the determined orientation.

[0037] The solution disclosed herein provides an omnidirectional fully driven vehicle with a simple structure and reduced cost. In addition, the omnidirectional vehicle has improved performance, stability and maneuverability with high precision, which may be critical for performing tasks such as precise handling of sensitive loads, precision landings, and missions where flight conditions vary (gusty winds, variable or moving payloads) or require complex and very demanding flight dynamics. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to complete this specification and to provide a better understanding of the present invention, a set of drawings is provided. The drawings constitute an integral part of the specification and illustrate embodiments of the present invention, which should not be interpreted as limiting the scope of the present invention, but as examples of how the present invention can be performed. The drawings include the following:

[0039] Figure 1 A perspective view of an omnidirectional vehicle with a rotary connection and a rotary encoder is shown in accordance with certain embodiments of the present invention.

[0040] Figure 2 Shows Figure 1 A detailed perspective view of one of the omnidirectional multirotor aircraft of the invention, with its rotary joint and rotary encoder.

[0041] Figure 3 Shows Figure 2 Detailed top view of the rotating connection.

[0042] Figure 4 Shows Figure 3Cross-sectional view of the rotating connection along line AA.

[0043] Figure 5A The slip ring is shown Figure 2 Detailed perspective view of the rotating connection.

[0044] Figure 5B Shows Figure 5A Detailed perspective view of a rotary connection, but including loose wires instead of slip rings.

[0045] Fig. 6A A block diagram of an omnidirectional vehicle with centralized management and power distribution subsystems according to certain embodiments of the present invention is shown.

[0046] Figure 6B A block diagram of an omnidirectional vehicle with a distributed management and power distribution subsystem is shown in accordance with certain embodiments of the present invention.

[0047] Figure 7 is a flow chart of a method for controlling an omnidirectional vehicle according to a certain embodiment of the present invention. DETAILED DESCRIPTION

[0048] In the following description, for the purpose of explanation, many specific details are set forth in order to provide a comprehensive understanding of the present system and method. However, it is apparent to those skilled in the art that the present apparatus, system and method can be implemented without these specific details. References to "examples" or similar language in the specification mean that the specific features, structures or characteristics described in conjunction with the example are included as described, but may not be included in other examples.

[0049] Figure 1 1 shows a perspective view of an omnidirectional vehicle 100 having a rotating connection and a rotary encoder according to a specific embodiment of the present invention. It should be understood that the exemplary omnidirectional vehicle 100 may include additional components and some of the components described herein may be removed and / or modified without departing from the scope of the exemplary omnidirectional vehicle 100. In addition, the implementation of the exemplary omnidirectional vehicle 100 is not limited to the following. Figure 1 Example shown.

[0050] The omnidirectional vehicle 100 includes a main body 101, arms 102a-d coupled to the main body 101 and extending radially therefrom, and four quadrotors 103a-d coupled to the respective arms 102a-d. Figure 1In the embodiment of the present invention, a pair of arms 102a / 102d and 102b / 102c respectively form a single longitudinal body, which is connected to the main body 101 by inserting a fastening element 104 directly attached to the main body 101, but in some other embodiments, each arm 102a-d can be a separate longitudinal body directly connected to the main body 101, or by inserting similar or different fastening elements. Each quadrotor 103a-d includes four rotors 105 rigidly attached to the frame 106 of the quadrotor 103a-d at a fixed position and orientation.

[0051] Each quadrotor 103a-d is connected to the corresponding arm 102a-d by the insertion of a rotary connection 107, which is in turn formed by a first rotary joint (not shown in this figure) connected to the corresponding arm 102a-d and a second rotary joint (not shown in this figure) vertically connected to the first rotary joint.

[0052] The main body 101 includes a planar elongated support element 108 to which is coupled a box 109 containing a battery and other electrical and electronic components (not shown). The box 109 is attached to the support element 108 by a fixing plate 110 and threaded studs 111. A controller 112 is attached to the top surface of the fixing plate 110, and the controller 112 is configured to control the functions of the entire omnidirectional vehicle 100, including the operation of the four quadrotors 103a-d. In addition, each rotor 105 has a separate electronic speed controller 113 attached to the frame 106 and located near them. These electronic speed controllers 113 include the hardware and software required to receive instructions from the controller 112 and control and adjust the speed of the motors of the rotors 105 based on the received instructions. They can also provide reversal and dynamic braking of the motors.

[0053] In such an embodiment, the omnidirectional vehicle 100 has been depicted as having four support legs 114 to support the omnidirectional vehicle when landing.

[0054] Although Figure 1 The embodiment shows all batteries located on the main body 101 and has a centralized management system with a single controller 112 located on the main body 101, but in some other embodiments, the batteries and controller can be distributed between the main body and the quadrotor.

[0055] In such an embodiment, the centers of rotation of the four quadrotors 103a-d are contained in the geometric axes of the main body arms 102a-d and in the plane defined by the propulsion module arms, thereby avoiding collisions between the quadrotors 103a-d and the main body 101 at every possible position of the quadrotors 103a-d relative to the main body 101.

[0056] exist Figure 1 In the illustrated embodiment, the quadrotors 103a-c are in their resting position and are contained in the same plane (plane XY) as the main body 101, while the quadrotor 103d has been rotated about 45º around the axis Y via a first rotational joint (not shown in this figure) and about 90º around the axis X via a second rotational joint (not shown in this figure) of the rotating connection 107.

[0057] Although Figure 1 The embodiment shows an omnidirectional vehicle 100 that includes four quadrotors 103a-d evenly distributed around a main body 101, but in some other embodiments, the omnidirectional vehicle may include a different number of orientable propulsion modules, different types of propulsion modules, a different number of propulsion units, different types of propulsion units, and a different distribution or configuration.

[0058] Figure 2 Shows Figure 1 Detailed perspective view of one of the orientable quadrotor aircraft 103a of the omnidirectional vehicle 100 with its rotary connection 107 and rotary encoder 115. The frame of the multirotor aircraft 103a is formed by two half-frames 106 connected to each other by a rotary shaft 117 inserted through the rotary connection 107. The rotor 105 is located at the free end of the half-frame 106.

[0059] Each rotor 105 has a protector guard 116 located below the motor 118 and the propeller 119, and the rotor 105 is actuated by a corresponding electronic speed controller 113, which is connected to the half-frame near the motor 108 and is connected to the controller 112 (not shown in this figure), from which it receives instructions for operating the rotor 105. The connection between the battery and the motor 118 and the electronic speed controller 113 is realized by a cable (not shown). The connection between the controller 112 and the electronic speed controller 113 can be realized by a cable or by a wireless connection (WiFi, Bluetooth, GSM, GPRS, etc.).

[0060] Figure 3 Shows Figure 2 Detailed top view of the rotating connector 107 of the omnidirectional vehicle 100. The arm 102a is fixedly connected to the main body 101 of the omnidirectional vehicle 100, and its free end is inserted into the rotating connector 107, so that the rotating connector can rotate around the arm 102a. The rotating shaft 117 of the quadrotor 103a passes through the rotating connector 107, so that the rotating shaft can rotate relative to the rotating connector 107, and the quadrotor 103a can also rotate relative to the rotating connector 107.

[0061] The magnetic rotary encoder 115.1 includes a metal ring 120.1, which is coupled to the outer surface of the rotary connection 107 corresponding to the hole into which the arm 102a is inserted. An annular printed circuit board 121.1 including sensors and all the remaining electrical and electronic components of the magnetic rotary encoder 115.1 is coupled to the metal ring 120.1 by threaded studs 122.1. The magnetic rotary encoder 115.1 also includes an annular magnet 123.1 coupled to the arm 102a. Another magnetic rotary encoder 115.2 also includes a metal ring 120.2, which is coupled to the outer surface of the rotary connection 107 corresponding to the hole into which the rotating shaft 117 of the quadrotor 103a is inserted. An annular printed circuit board 121.2 including sensors and all the remaining electrical and electronic components of the magnetic rotary encoder 115.2 is coupled to the metal ring 120.2 by threaded studs 122.2. The magnetic rotary encoder 115.2 also includes a ring magnet 123.2 coupled to the arm 102a.

[0062] The magnetic rotary encoder 115.1-2 can use two or more magnetic poles located in the corresponding magnet 123.1-2 to indicate the encoder position of the magnetic sensor (usually magnetoresistive or Hall effect) located in the printed circuit board 121.1-2. The magnetic sensor reads the magnetic pole position. The code can be read by a control device (such as a microprocessor or microcontroller located in the printed circuit board 121.1-2) to determine the angle of the axis (particularly the arm 102a and the rotating axis 117) relative to the rotating connection 107. Optionally, the code can be sent to a controller located in the main body 101 (in the case of an omnidirectional vehicle with a centralized management structure) or a controller located in the quadrotor 103a (in the case of a distributed management structure). The code can be converted into an absolute angle by using a dedicated algorithm. Magnetic rotary encoders are particularly convenient in situations where other types of encoders may fail due to dust or debris accumulation. Magnetic rotary encoders are also relatively insensitive to vibration, slight misalignment or shock.

[0063] The combination of the readings of the two rotary encoders 115 . 1 - 2 of the rotary connection 107 will provide the orientation of the quadrotor 103 a relative to the main body 101 .

[0064] Figure 4 Shows Figure 3The rotating connection 107 and the remaining elements shown in the figure are cross-sectional views along the line AA. The rotating connection 107 is a rectangular solid block having a first aperture 123, through which the free end of the arm 102a is inserted, and the rotating connection 107 rotates around the first aperture 123 by the insertion of the first friction bushing 124a. The rotating connection 107 also includes a second aperture 125 perpendicular to the first aperture 123, and the rotating shaft 117 connected to the quadrotor 103a is inserted into the second aperture 125, and the rotating shaft 117 rotates relative to the rotating connection 107 in the second aperture 125 by the insertion of the second friction bushing 124b. Although Figure 4 The embodiment shown in FIG. 1 shows arms 102a and rotation axis 117 as hollow tubes to reduce the weight of the vehicle, but they may also be solid rods.

[0065] Since the rotational movement of the rotating connector 107 relative to the arm 102a is completely independent of the rotational movement of the rotating shaft 117 relative to the rotating connector 107, the arm 102 and the rotating shaft 117 do not contact each other, and there is an empty space between the two holes 123, 125. Alternatively, a portion of the rotating connector 107 may separate the two holes 123, 125, instead of there being an empty space.

[0066] Although Figures 1 to 4 Four magnetic rotary encoders are shown for measuring the angles of the axes (in particular the arms and the axis of rotation) relative to the rotary connection, but other types of rotary encoders capable of performing said measurements may be used (for example optical encoders, capacitive encoders, resistive encoders, etc.). In any case, these rotary encoders 115.1-2 are elements external to the rotary connection 107, which avoids having to design the rotary connection with an internal space communicating with the arms 102a and the axis of rotation 117 in order to combine gyroscopes, accelerometers or any other inertial measurement unit to determine the orientation of the quadrotor 102a relative to the body 101. This significantly simplifies the design of the omnidirectional vehicle, reduces its manufacturing and maintenance costs, and makes the measurement of the relative position of the quadrotor relative to the cabin more reliable.

[0067] Figure 5A Shows Figure 2Detailed perspective view of the rotating connection 107 of the quadrotor 103a, which includes a first slip ring 126a for connecting the fixed element (arm 102a) to the rotating system (rotating connection 107), a second slip ring 126b for connecting the rotating connection 107 to one of the frames 106 of the quadrotor 103a, and a third slip ring 126b for connecting the rotating connection 107 to another of the frames 106 of the quadrotor 103a. The first connection ring 127a of the first slip ring 126a is fixedly attached to the arm 102a, and is connected to the wire 128 from the main body 101, and transmits data from the controller 112 and / or power from the battery. The second connection ring 129a of the first slip ring 126a is rotatably coupled to the arm 102a and fixedly coupled to the rotating connection 107 by means of a rigid member 132a, and is connected to a wire 130 for transmitting data and / or power from the slip ring 126 to the electronic speed controller 113 via the second slip ring 126b, the third slip ring 126c and the printed circuit board 121.1-2 of the rotary encoder 115.1-2. The second slip ring 126b and the third slip ring 126c include respective first connection rings 127b-c fixedly attached to the rotating shaft 117, which are connected to the respective electronic speed controllers 113 via wires 133 to transmit data from the controller 112 and / or power from the battery. The second slip ring 126b and the third slip ring 126c also include respective second connection rings 129b-c rotatably coupled to the rotating shaft 117 and fixedly coupled to the rotating connection 107 by means of a rigid member 132b-c. These second connection rings 129b-c are also connected to wires 130, which transmit data and / or power from the first slip ring 126 to the second slip ring 126b and the third slip ring 126c. The corresponding first connection rings 127a-c and second connection rings 129a-c are internally connected to each other on their inner connection surfaces for data and / or power transmission. The wires 130 are also connected to the rotating connection 107 by clamps, fasteners or the like 134.

[0068] Figure 5B Shown as Figure 5A Detailed perspective view of the rotating connector 107 of FIG. 101 , but including loose wires 131 instead of slip rings 126a-c. The controller 112 or electronic speed controller 113 can implement an automatic unwinding algorithm to limit the number of turns the loose wires 131 can have. Alternatively or in combination, the rotating connector 107 can integrate a mechanical limit to limit the number of turns the loose cables 131 can have. The loose cables 131 allow data and power to be transmitted between the main body 101 and the quadrotor 103a. These loose wires 131 are also connected to the rotating connector 107 by clamps, fasteners or the like 135.

[0069] In some other embodiments, the omnidirectional vehicle may integrate some other devices for data and power transmission, such as a wireless transmission subsystem capable of transmitting data and power between the main body and the quadrotor, and vice versa.

[0070] Fig. 6A 200. A block diagram of an omnidirectional vehicle with a centralized management and distribution subsystem according to a specific embodiment of the present invention is shown. It should be understood that the exemplary omnidirectional vehicle 200 may include additional components and that some of the components described herein may be removed and / or modified without departing from the scope of the exemplary omnidirectional vehicle 200. In addition, the implementation of the exemplary omnidirectional vehicle 200 is not limited to the following. Fig. 6A Example shown.

[0071] In this embodiment, the omnidirectional vehicle 200 includes a main controller 202 located in the main body 201 and configured to operate multiple orientable quadcopters 204a-d. In addition, the omnidirectional vehicle 200 includes a single battery or battery pack 203 in the main body 201 to power the orientable quadcopters 204a-d and the remaining electrical and electronic components of the vehicle 200. Data and power can be transmitted from the main body 201 to the orientable quadcopters 204a-d via slip rings or loose cables 205. This embodiment shows an omnidirectional vehicle with a centralized control and power distribution structure, which is particularly convenient for reducing costs, minimizing components that may fail, facilitating assembly of the vehicle, reducing the inertia of the propulsion module, and making the system more flexible and efficient.

[0072] Figure 6B 1 shows a block diagram of an omnidirectional vehicle 300 with a distributed management and distribution subsystem according to a specific embodiment of the present invention. It should be understood that the exemplary omnidirectional vehicle 300 may include additional components and some of the components described herein may be removed and / or modified without departing from the scope of the exemplary omnidirectional vehicle 300. In addition, the implementation of the exemplary omnidirectional vehicle 300 is not limited to the following. Figure 6B Example shown.

[0073] In such an embodiment, the omnidirectional vehicle 300 includes a main controller 302 located in the main body 301 and a plurality of secondary controllers 305, each of which is located in a corresponding directional propulsion module 304a-d. The plurality of secondary controllers 305 are configured to operate the corresponding directional propulsion modules 304a-d to which they are installed, and the main controller 302 is configured to manage the plurality of secondary controllers 305. Preferably, the battery 303 of the main body 301 powers the electrical and electronic components of the main body 301, while the battery 306 in the directional propulsion modules 304a-d powers the electrical and electronic components of the corresponding propulsion modules 304a-d. However, since data and power can be transmitted from the main body 301 to the directional propulsion modules 304a-d and vice versa, in the event of any battery failure or battery exhaustion, power can be transmitted from the main body 301 or any directional propulsion module 304a-d to any component within the omnidirectional vehicle 300. This embodiment shows an omnidirectional vehicle with a distributed control and power distribution structure, wherein, in the event of failure of the controller currently responsible for managing the omnidirectional vehicle, any one of the multiple controllers can control the entire vehicle. In addition, control redundancy increases the safety and reliability of the vehicle, while power redundancy increases the operational autonomy of the vehicle.

[0074] Figure 7 is a flow chart of a method 400 for controlling an omnidirectional vehicle according to certain embodiments of the present invention.

[0075] In step 401 of method 400, an omnidirectional vehicle as described above is provided. Preferably, the omnidirectional vehicle provided will be an overdriven omnidirectional vehicle. In step 402 of method 400, the displacement of the main body of the omnidirectional vehicle in Cartesian space is determined. Thereafter, in step 403 of method 400, a controller of the omnidirectional vehicle determines the thrust and orientation of the omnidirectional vehicle based on the desired displacement. In step 404 of method 400, the controller further determines the thrust and orientation of each of a plurality of orientable propulsion modules based on the determined thrust and orientation of the omnidirectional vehicle. Then, in step 405 of method 400, the controller adjusts the tilt angle of each of the plurality of orientable propulsion modules by performing a rotational movement of each orientable propulsion module relative to the main body via a rotating connection, the relative rotational movement being based on the determined orientation.

[0076] In this document, the term “include” and its derivatives (such as “comprises” etc.) should not be understood as being exclusive, that is, these terms should not be interpreted as excluding the possibility that the described and defined contents may include other elements.

[0077] The invention is obviously not limited to the particular embodiments described herein, but also covers any variant that may be conceived by anyone skilled in the art within the general scope of the invention as defined by the claims.

Claims

1. An omnidirectional vehicle (100), include: Main body (101); a plurality of arms (102a-d) radially extending from and coupled to the body portion (101); and a plurality of orientable propulsion modules (103a-d), each orientable propulsion module (103a-d) coupled to a respective arm (102a-d) and comprising at least three propulsion units (105), wherein the at least three propulsion units (105) are rigidly attached to a frame (106) of the respective propulsion module (103a-d) at respective fixed positions and orientations; Characterized in that each orientable propulsion module (103a-d) is connected to the corresponding arm (102a-d) by the insertion of a rotational connection (107), the rotational connection being formed by a first passive rotational joint connected to the arm (102a-d) and a second passive rotational joint connected to the orientable propulsion module (103a-d), wherein the rotation axis of the second rotational joint is perpendicular to the rotation axis of the first rotational joint and is coplanar with the rotation axis of the first rotational joint; wherein the first rotational joint is configured to allow the orientable propulsion module (103a-d) to rotate around the arm (102a-d), and the second rotational joint is configured to allow the orientable propulsion module (103a-d) to rotate around a rotation axis (117) perpendicular to the arm (102a-d), so that the orientable propulsion module (103a-d) is provided with two degrees of freedom relative to the main body (101); and A rotary encoder (115) is included near each rotary joint, and the rotary encoder (115) is configured to monitor the orientation of each orientable propulsion module (103a-d) relative to the main body (101).

2. The omnidirectional vehicle (100) according to claim 1, in, Each rotating connection member (107) includes a body having a first aperture (123) and a second aperture (125), the corresponding arm (102a-d) being inserted through the first aperture (123) and the rotating connection member (107) rotating around the first aperture (123), the second aperture (125) being perpendicular to the first aperture (123), and the rotating shaft (117) connected to the corresponding orientable propulsion module (103a-d) being inserted through the second aperture (125) and rotating within the second aperture (125).

3. The omnidirectional vehicle (100) according to any one of the preceding claims, in, The center of rotation of the propulsion module is located on the geometric axis of the plurality of arms (102a-d) and is coplanar with the geometric axis of the frame (106) of the orientable propulsion module (103a-d).

4. The omnidirectional vehicle (100) according to any one of the preceding claims, in, Each propulsion unit (105) is an independently controllable propulsion unit and is configured to generate an independent thrust modulus.

5. The omnidirectional vehicle (100) according to claim 4, in, Each propulsion unit (105) is configured to generate a torque that is dependent on or independent of the thrust modulus generated.

6. The omnidirectional vehicle (100) according to any one of the preceding claims, in, The at least one propulsion unit (105) is selected from the group consisting of a rotor, a propeller, a turboprop engine, a jet engine, and any combination thereof.

7. An omnidirectional vehicle (100) according to any one of the preceding claims, comprising a landing gear, or a plurality of landing gears, attached to the lower surface of the main body (101), each landing gear being attached to the lower surface of a respective orientable propulsion module.

8. The omnidirectional vehicle (100) according to any one of the preceding claims, in, The center of mass of the orientable propulsion modules (103a-d) in the landing configuration is located below the center of rotation of their respective rotational connections (107).

9. The omnidirectional vehicle (100) according to any one of the preceding claims, in, The omnidirectional orientable vehicle (103a-d) is selected from the group consisting of an omnidirectional air vehicle, an omnidirectional underwater vehicle, an omnidirectional outer space vehicle, or any combination thereof.

10. The omnidirectional vehicle (100) according to any one of the preceding claims, comprising a slip ring (126a-c) electrically connecting the main body (101) and the orientable propulsion module (103a-d), the slip ring (126a-c) being configured to allow at least one of data and power to be transmitted between the main body (101) and the orientable propulsion module (103a-d).

11. An omnidirectional vehicle (100) according to any one of claims 1 to 9, comprising a loose cable (131) electrically connecting the main body (101) and the orientable propulsion module (103a-d), the loose cable (131) being combined with an automatic unwinding algorithm or a mechanical limit on the number of turns of the loose cable (131), and being configured to allow at least one of data and power to be transmitted between the main body (101) and the orientable propulsion module (103a-d).

12. The omnidirectional vehicle (200) according to any one of the preceding claims, comprising a controller (202) located in the main body (201), the controller (202) being configured to operate the plurality of orientable propulsion modules (204a-d).

13. The omnidirectional vehicle (300) according to any one of claims 1 to 11, include: A main controller (302), the main controller (302) being located in the main body (301); as well as a plurality of secondary controllers (305), each secondary controller (305) being located in a corresponding orientable propulsion module (304a-d); Each secondary controller (305) is configured to operate the corresponding orientable propulsion module (304a-d) installed thereon, and the main controller (302) is configured to manage the plurality of secondary controllers (304a-d).

14. The omnidirectional vehicle (100) according to any one of the preceding claims, in, The omnidirectional vehicle (100) is an overdriven omnidirectional vehicle.

15. A method (400) for controlling an omnidirectional vehicle, include: Arranging (401) an omnidirectional vehicle as claimed in any one of the preceding claims, preferably the omnidirectional vehicle comprises an overdriven omnidirectional vehicle; Determining (402) a displacement of a main body of the omnidirectional vehicle in Cartesian space; determining (403) a thrust and an orientation of the omnidirectional vehicle based on the determined displacement by a controller of the omnidirectional vehicle; determining ( 404 ), by the controller, thrust and orientation of each of the plurality of orientable propulsion modules based on the determined thrust and orientation of the omnidirectional vehicle; as well as The tilt angle of each of the plurality of orientable propulsion modules is adjusted (405) by the controller by performing a rotational movement of each orientable propulsion module relative to the main body via the rotational connection, wherein the relative rotational movement is based on the determined orientation.

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