A force-position integrated actuator for automatic control of vehicle pedals

Abstract

The present invention discloses a force-position integrated actuator for automatic control of a vehicle pedal, belonging to the technical field of automobile test equipment. The present invention includes a force-position integrated electric cylinder and a pedal connection tooling. The force-position integrated electric cylinder includes: a servo motor, a transmission assembly, a piston rod, a cylinder body, a sealing gasket, a sensor, and an electrical interface. The pedal connection tooling includes: a spline screw, a spline screw nut, a fixing nut, and a U-shaped connector. The internal rotor of the servo motor is integrated with the screw, the spline screw nut is fixedly connected to the protruding end of the piston rod, and the vehicle pedal and the pedal connection tooling are tightly fitted through the U-shaped connector. The present invention reduces the friction of the connection assembly and improves the transmission efficiency by integrating the servo motor rotor with the screw. The electric cylinder integrates a force sensor to achieve high-precision force-position integrated closed-loop control. The pedal connection tooling can limit the direction of the force and reduce the probability of pedal damage.

Description

Technical Field

[0001] The invention relates to a force-position integrated actuator for automatic control of a vehicle pedal, belonging to the technical field of automobile test equipment. Background Art

[0002] Pre-market vehicle testing is crucial, leading to the emergence of autonomous driving robots for vehicle testing. Existing autonomous driving robots often utilize rocker-arm, leg-type, or screw-type actuators, which suffer from low control accuracy and susceptibility to oscillation. They often use external force sensors to measure pedal force, but these sensors' mounting methods are limited by the movement of the actuator structure and can easily damage them. The pedals are often fixed to the actuator, creating the risk of reverse pull on the pedals, potentially damaging them.

[0003] How to accurately and safely control the accelerator or brake pedal, fully consider the force applied to the pedal, and quickly adapt to different vehicle models are urgent issues that need to be addressed by the actuators of autonomous driving robots. Summary of the Invention

[0004] The purpose of the present invention is to provide a force-position integrated actuator for automatic control of vehicle pedals, so as to solve the problems of inconvenient force measurement of the pedals of autonomous driving vehicles and the susceptibility of the pedals to damage.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The present invention provides a force-position integrated actuator for automatic control of a vehicle pedal, comprising: a force-position integrated electric cylinder and a pedal connection tooling;

[0007] The force-position integrated electric cylinder includes: a servo motor, a transmission assembly, a piston rod, a cylinder body, a sealing gasket, a force sensor, a rotary encoder and an electrical interface;

[0008] The transmission assembly is located inside the cylinder body and includes: a screw, a screw nut and a bearing, which converts the rotation of the servo motor into the linear motion of the piston rod;

[0009] The servo motor is installed inside the cylinder body, and the internal rotor of the servo motor is integrally connected with the lead screw, thereby reducing friction caused by the connection of the transmission component and improving work efficiency;

[0010] The piston rod slides in the cylinder body, and the piston rod is fixedly connected to the lead screw;

[0011] The screw nut fixes the position where the screw is installed;

[0012] One end of the piston rod extends out of the cylinder body, and the sealing gasket is installed at the outlet of the cylinder body to prevent the leakage of lubricating oil and dust from entering the interior of the cylinder body;

[0013] The bearing is installed at the connection between the servo motor and the lead screw to reduce friction;

[0014] The force sensor is fixedly mounted on the end of the cylinder body, and the force of the vehicle pedal is transmitted to the surface of the force sensor through the force-position integrated electric cylinder, so as to measure the force applied by the force-position integrated electric cylinder to the vehicle pedal;

[0015] The rotary encoder is mounted on the rotor of the servo motor. The rotation of the servo motor rotor drives the rotary encoder to rotate together. The displacement value of the piston rod is indirectly obtained by measuring the rotation angle.

[0016] The electrical interface is mounted on the cylinder body to achieve a safe and stable electrical connection;

[0017] The pedal connection tooling includes: a spline screw, a spline screw nut, a fixing nut and a U-shaped connector;

[0018] The cross-section of one end of the spline screw is shaped like a petal, and the other end is spherical. The edge of the petal end of the spline screw can prevent radial rotation between the spline screw and the spline screw nut. The spherical end of the spline screw is hinged to the spherical surface of the fixing nut to adjust the direction of the output force of the piston rod and prevent the force from being offset and causing damage to the structure.

[0019] One end of the spline screw nut is engaged with the spline screw, and the other end of the spline screw nut is fixedly connected to the protruding end of the piston rod;

[0020] The U-shaped connector is tightly fitted to the vehicle pedal via the fixing nut;

[0021] During operation, the servo motor directly drives the lead screw to rotate, and the lead screw converts the rotation into linear motion and transmits it to the piston rod. The displacement of the piston rod is determined by the rotary encoder, and the force applied to the front end of the piston rod is determined by the force sensor. One end of the pedal connecting fixture is fixedly connected to the force-position integrated electric cylinder, and the other end of the pedal connecting fixture is tightly fitted with the accelerator pedal or the brake pedal. The piston rod force acts perpendicularly on the vehicle pedal surface along the stepping direction through the pedal connecting fixture.

[0022] Through the pedal connection fixture, the force-position integrated electric cylinder transmits the force to the vehicle pedal along the spline screw; when the force-position integrated electric cylinder retracts, the surface of the spline screw is smooth, and the force of the force-position integrated electric cylinder cannot act in reverse on the vehicle pedal, so the vehicle pedal retracts naturally, ensuring that the force on the vehicle pedal is unidirectional and protecting the vehicle pedal from damage;

[0023] Furthermore, the integrated actuator is installed on the vehicle, and by controlling the movement of the servo motor, the vehicle pedals can be automatically controlled according to instructions, realizing an autonomous driving robot to assist the vehicle in completing the autonomous driving task.

[0024] Beneficial effects:

[0025] 1. The force-position integrated actuator for automatic control of vehicle pedals of the present invention adopts an integrated connection method of the servo motor rotor and the lead screw, which reduces the friction caused by the connection of the transmission components and effectively improves the transmission efficiency.

[0026] 2. The force-position integrated actuator for automatic control of vehicle pedals of the present invention integrates the force sensor inside the electric cylinder to achieve high-precision force-position integrated closed-loop control without affecting the reciprocating motion of the force-position integrated electric cylinder.

[0027] 3. The force-position integrated actuator for automatic control of vehicle pedals of the present invention adopts a pedal connection tooling, which can limit the direction of the force of the force-position integrated electric cylinder and effectively reduce the probability of damage to the vehicle pedal. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the force-position integrated electric cylinder structure;

[0029] Among them, 1-piston rod, 2-sealing gasket, 3-cylinder body, 4-screw, 5-screw nut, 6-bearing, 7-electrical interface, 8-rotary encoder, 9-force sensor, 10-servo motor;

[0030] Figure 2 1. It is a schematic diagram of the pedal connection tooling structure;

[0031] Among them, 11-spline screw, 12-spline screw nut, 13-fixing nut, 14-U-shaped connecting piece. DETAILED DESCRIPTION

[0032] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below with reference to the accompanying drawings and examples.

[0033] Example 1:

[0034] A force-position integrated actuator for automatic control of a vehicle pedal in an embodiment includes: a force-position integrated electric cylinder and a pedal connection tooling;

[0035] like Figure 1 As shown, the force-position integrated electric cylinder includes: a servo motor 10, a transmission assembly, a piston rod 1, a cylinder body 3, a sealing gasket 2, a force sensor 9, a rotary encoder 8 and an electrical interface 7;

[0036] The transmission assembly is located inside the cylinder 3 and includes: a screw 4, a screw nut 5 and a bearing 6, which converts the rotation of the servo motor 10 into the linear motion of the piston rod 1;

[0037] The servo motor 10 is installed inside the cylinder 3, and the internal rotor of the servo motor 10 is integrally connected with the lead screw 4, which reduces the friction caused by the connection of the transmission components and improves work efficiency;

[0038] In the embodiment, the servo motor 10 is a permanent magnet synchronous motor;

[0039] The piston rod 1 slides in the cylinder 3 and is fixedly connected to the lead screw 4;

[0040] The screw nut 5 fixes the position where the screw 4 is installed;

[0041] One end of the piston rod 1 extends out of the cylinder 3, and a sealing gasket 2 is installed at the outlet of the cylinder 3 to prevent lubricating oil from leaking and dust from entering the cylinder 3;

[0042] The bearing 6 is installed at the connection between the servo motor 10 and the lead screw 4 to reduce friction;

[0043] The force sensor 9 and the rotary encoder 8 are respectively installed at the ends of the cylinder body 3. The rotary encoder 8 is connected to the servo motor 10 to measure the force and displacement of the piston rod 1 during the movement of the force-position integrated electric cylinder.

[0044] In the embodiment, the force sensor 9 adopts a strain gauge force sensor, and the rotary encoder 8 adopts a 12-bit incremental photoelectric encoder;

[0045] The electrical interface 7 is installed on the cylinder body 3 to achieve a safe and stable electrical connection;

[0046] The pedal connection tooling includes: a spline screw 11, a spline screw nut 12, a fixing nut 13 and a U-shaped connector 14;

[0047] One end of the spline screw 11 has a petal-like cross-section and the other end is spherical. The edges of the petal end of the spline screw 11 can prevent radial rotation between the spline screw 11 and the spline screw nut 12. The spherical end of the spline screw 11 is spherically hinged to the fixing nut 13 to adjust the direction of the output force of the piston rod 1 and prevent the force from being offset and causing damage to the structure.

[0048] One end of the spline screw nut 12 is engaged with the spline screw 11, and the other end of the spline screw nut 12 is fixedly connected to the protruding end of the piston rod 1;

[0049] The U-shaped connector 14 is tightly fitted to the vehicle pedal via the fixing nut 13;

[0050] During operation, the servo motor 10 directly drives the lead screw 4 to rotate, and the lead screw 4 converts the rotation into linear motion and transmits it to the piston rod 1. The displacement of the piston rod 1 is determined by the rotary encoder 8, and the force on the front end of the piston rod 1 is determined by the force sensor 9. One end of the pedal connecting fixture is fixedly connected to the force-position integrated electric cylinder, and the other end of the pedal connecting fixture is tightly fitted with the accelerator pedal or brake pedal. The displacement and force of the piston rod 1 act perpendicularly on the vehicle pedal surface along the stepping direction through the pedal connecting fixture;

[0051] Through the pedal connection fixture, the force-position integrated electric cylinder transmits the force to the vehicle pedal along the spline screw 11; when the integrated electric cylinder retracts, the surface of the spline screw 11 is smooth, and the force of the force-position integrated electric cylinder cannot act in the opposite direction on the vehicle pedal. The vehicle pedal can only retract naturally, ensuring that the force on the vehicle pedal is unidirectional and protecting the vehicle pedal from damage.

[0052] Furthermore, the integrated actuator is installed on the vehicle, and by controlling the movement of the servo motor 10, the vehicle pedals can be automatically controlled according to instructions, realizing an automatic driving robot to assist the vehicle in completing the automatic driving task.

[0053] The above specific description further illustrates the purpose, technical solutions and beneficial effects of the invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A force-position integrated actuator for automatic control of vehicle pedals, characterized by: include: Force-position integrated electric cylinder and pedal connection tooling; The force-position integrated electric cylinder comprises: a servo motor (10), a transmission assembly, a piston rod (1), a cylinder body (3), a sealing gasket (2), a force sensor (9), a rotary encoder (8) and an electrical interface (7); The transmission assembly is located inside the cylinder body (3) and includes: a screw (4), a screw nut (5) and a bearing (6), which converts the rotation of the servo motor (10) into the linear motion of the piston rod (1); The servo motor (10) is installed inside the cylinder (3), and the internal rotor of the servo motor (10) is integrally connected with the lead screw (4), thereby reducing friction caused by the connection of the transmission components and improving work efficiency; The piston rod (1) slides in the cylinder body (3), and the piston rod (1) is fixedly connected to the lead screw (4); The screw nut (5) fixes the position where the screw (4) is installed; One end of the piston rod (1) extends out of the cylinder body (3), and a sealing gasket (2) is installed at the outlet of the cylinder body (3) to prevent lubricating oil from leaking and dust from entering the interior of the cylinder body (3); The bearing (6) is installed at the connection between the servo motor (10) and the lead screw (4) to reduce friction; The force sensor (9) is fixedly mounted on the end of the cylinder body (3), and the force of the vehicle pedal is transmitted to the surface of the force sensor (9) through the force-position integrated electric cylinder, so as to measure the force exerted by the force-position integrated electric cylinder on the vehicle pedal; The rotary encoder (8) is mounted on the rotor of the servo motor (10). The rotor of the servo motor (10) rotates, driving the rotary encoder (8) to rotate together. By measuring the rotation angle, the displacement value of the piston rod (1) is indirectly obtained. The electrical interface (7) is mounted on the cylinder body (3) and is used to achieve a safe and stable electrical connection; The pedal connection tooling comprises: a spline screw (11), a spline screw nut (12), a fixing nut (13) and a U-shaped connecting piece (14); One end of the spline screw (11) has a cross-section shaped like a petal, and the other end is spherical. The edges of the petal end of the spline screw (11) can prevent radial rotation between the spline screw (11) and the spline screw nut (12). The spherical end of the spline screw (11) is spherically hinged to the fixed nut (13) to adjust the direction of the output force of the piston rod (1) and prevent the structure from being damaged due to the deviation of the force. One end of the spline screw nut (12) is engaged with the spline screw (11), and the other end of the spline screw nut (12) is fixedly connected to the protruding end of the piston rod (1); The U-shaped connecting piece (14) is tightly fitted to the vehicle pedal via a fixing nut (13); During operation, the servo motor (10) directly drives the lead screw (4) to rotate, and the lead screw (4) converts the rotation into linear motion and transmits it to the piston rod (1). The displacement of the piston rod (1) is determined by the rotary encoder (8), and the force applied to the front end of the piston rod (1) is determined by the force sensor (9). One end of the pedal connecting tool is fixedly connected to the force-position integrated electric cylinder, and the other end of the pedal connecting tool is tightly fitted with the accelerator pedal or the brake pedal. The force applied by the piston rod (1) acts perpendicularly on the surface of the vehicle pedal along the stepping direction through the pedal connecting tool. The force-position integrated electric cylinder transmits the force to the vehicle pedal along the spline screw (11) through the pedal connection tooling; when the force-position integrated electric cylinder retracts, the surface of the spline screw (11) is smooth, and the force of the force-position integrated electric cylinder cannot act in reverse on the vehicle pedal, so the vehicle pedal retracts naturally, ensuring the unidirectional force on the vehicle pedal and protecting the vehicle pedal from damage.

2. The force-position integrated actuator for automatic vehicle pedal control according to claim 1, characterized in that: When installed on a vehicle, the vehicle pedals can be automatically controlled according to instructions by controlling the movement of the servo motor (10), thereby realizing an automatic driving robot and assisting the vehicle in completing the automatic driving task.

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