Intelligent scooter chassis

Abstract

The utility model discloses a kind of intelligent scooter chassis, belong to low-speed electric scooter technical field, to solve the problem of traditional chassis structure loose, large space occupation, low transmission efficiency, inconvenient operation and maintenance. It includes front frame, line control steering assembly, bottom plate frame and main frame;Line control steering assembly upper connection steering wheel, below connection front frame, bottom plate frame front end connection front frame, rear end connection main frame, battery is equipped below main frame, rear connection rear suspension spring;Rear suspension spring connection longitudinal suspension, drive brake assembly is fixed in longitudinal suspension, and is connected with wheel. The utility model realizes high integration, improves space utilization and transmission efficiency, simplifies assembly maintenance, applicable to old scooter, electric wheelchair car etc., improves ride comfort and use safety.

Description

Technical Field

[0001] This utility model belongs to the field of low-speed electric vehicle technology, specifically relating to an intelligent mobility scooter chassis, suitable for small, low-speed mobile platforms such as elderly mobility scooters and electric wheelchairs. Through the high integration and optimization of the mechanical structure, it improves the chassis space utilization, transmission efficiency and handling stability, while simplifying the assembly and maintenance process, meeting the needs of elderly and mobility-impaired users. Background Technology

[0002] As a short-distance travel tool, the chassis of a low-speed electric mobility scooter is the core component that bears the weight of the entire vehicle and enables its driving, braking, and steering functions. Currently, most mobility scooter chassis employ a decentralized mechanical design, with the driving, braking, and steering systems arranged independently, resulting in significant technical shortcomings.

[0003] In terms of the drive system, traditional solutions often use a single motor shared by both left and right wheels, along with a main reducer, to transmit power to the rear wheels via a driveshaft. This structure requires additional driveshaft brackets and connecting components, occupying a significant amount of chassis space. Furthermore, the power transmission path is long, passing through multiple stages including the motor, reducer, and driveshaft. Mechanical clearances and friction at each stage cause energy loss, reducing transmission efficiency and shortening the vehicle's driving range.

[0004] Braking systems are mostly independent mechanical drum or disc structures, installed at the wheel or final drive end. They require separate design of brake lines and control linkages, which not only increases chassis complexity but also causes braking response delays. Steering systems rely on mechanical steering wheels and steering linkages. The numerous linkages and joints occupy longitudinal chassis space, have large mechanical clearances, and result in low steering accuracy. Adjustments and maintenance require individual calibration of linkage positions, making the process cumbersome.

[0005] Furthermore, the backup brake release devices in existing chassis are mostly located underneath the chassis, requiring elderly users to bend over or squat to operate them, which is inconvenient. At the same time, the dispersed layout of the drive, braking, and steering systems results in a large overall chassis size, hindering the rational placement of critical components such as the battery, increasing the difficulty of vehicle assembly, and reducing production efficiency. As the requirements for space utilization and handling safety in mobility vehicles increase, the traditional dispersed chassis can no longer meet actual usage needs. Utility Model Content

[0006] This utility model addresses the problems of existing intelligent mobility vehicle chassis, such as loose structure, large space occupation, low transmission efficiency, high energy loss, insufficient steering and braking control precision, inconvenient operation of backup brake, and cumbersome assembly and maintenance. This utility model provides an intelligent mobility vehicle chassis that optimizes the mechanical structure layout, shortens the power transmission path, improves control precision and ease of operation, and simplifies the assembly process by integrating drive and braking with steer-by-wire design.

[0007] This utility model is achieved through the following technical solution: a smart mobility vehicle chassis, including a front frame, a steer-by-wire assembly, a base frame, and a main frame; the steer-by-wire assembly is connected to a steering wheel at the top and to the front frame at the bottom, the base frame is connected to the front frame at the front end and to the main frame at the rear end, a battery is located under the main frame and a rear suspension spring is connected at the rear; the rear suspension spring is connected to a longitudinal suspension, and the drive and braking assembly is fixed in the longitudinal suspension and connected to the wheels.

[0008] Furthermore, the drive and braking assembly integrates a reducer, a brushless motor, a magnetic encoder, and an electromagnetic brake in sequence along the power axis, with the wheels and the reducer output shaft connected by surface contact.

[0009] Furthermore, the reducer is a multi-stage planetary gear transmission structure with a reduction ratio greater than 10:1.

[0010] Furthermore, the steer-by-wire assembly includes an input module, a brain module, and an output module.

[0011] Furthermore, one end of the longitudinal suspension is designed with a lug, and one end of the rear suspension spring is connected to the longitudinal suspension via an elastic bushing, while the other end is connected to a lug under the main frame.

[0012] Furthermore, the braking clamping force of the electromagnetic brake acts on the drive shaft of the brushless motor, working in conjunction with the brushless motor to achieve deceleration, regenerative braking, or mechanical parking brake.

[0013] Furthermore, the magnetic encoder is directly mounted on the output shaft of the brushless motor to collect the angular position and rotational speed data of the brushless motor.

[0014] Furthermore, the input module includes a steering wheel, a sensor assembly, and a motor.

[0015] Furthermore, the output module uses a motor as the core drive element, and the motor is integrated inside the steer-by-wire assembly.

[0016] In summary, this utility model has the following beneficial effects: (1) The wheels, rear suspension springs, longitudinal suspension, and drive and brake assemblies are highly integrated into a single design, which can be directly installed on the main frame, greatly simplifying the final assembly process and reducing assembly steps; the drive and brake assemblies pass through the longitudinal suspension arms, making full use of the internal space of the suspension, reducing the space occupied by redundant parts, reserving sufficient layout space for key components such as batteries under the main frame, and optimizing the overall space allocation of the chassis.

[0017] (2) The transmission and braking performance has been significantly optimized. The drive and braking assembly integrates core components along the power axis, shortens the power transmission path, reduces energy loss caused by mechanical clearance and friction, improves transmission efficiency and extends vehicle range. The electromagnetic brake clamping force acts directly on the motor drive shaft. The braking force can be amplified by the reducer. It is also controlled in coordination with the brushless motor through the same corner module controller. The braking response is rapid. It can also realize multiple functions such as motor deceleration, regenerative braking and mechanical parking, and has stronger reliability.

[0018] (3) Steering precision and handling experience are significantly improved. The steer-by-wire assembly eliminates mechanical connections and captures steering intentions in real time through high-precision sensors in the sensor assembly. The motor can simulate real steering feel. Combined with double wishbone suspension and front suspension springs, it further enhances handling stability and driving comfort.

[0019] (4) Ride comfort and structural reliability are steadily improved. The elastic bushings of the longitudinal suspension have built-in rubber bodies, which can absorb road impact and vibration through elastic deformation. The rear suspension spring connects the longitudinal suspension and the main frame. The two work together to reduce the transmission of impact to the seat, effectively protect the user's waist and reduce driving fatigue. The key connection parts adopt the surface contact bolt connection method, which makes the load and impact transmission more uniform, disperses structural stress, and extends the service life of the overall machinery. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the chassis of an intelligent mobility scooter according to the present invention; Figure 2 Schematic diagram of the steering actuator assembly; Figure 3 This is a schematic diagram of the assembly of the main frame and wheels of this utility model; Figure 4 This is a schematic diagram of the assembly of the main frame and the longitudinal suspension of this utility model; Figure 5 This is a schematic diagram of the longitudinal suspension structure of this utility model; Figure 6 This is a schematic diagram of the drive and braking assembly structure of this utility model; Figure 7 A flowchart illustrating the workflow of an intelligent mobility vehicle chassis.

[0021] Reference numerals: 1. Front frame; 2. Steer-by-wire assembly; 3. Steering wheel; 4. Underbody frame; 5. Main frame; 6. Wheel; 7. Rear suspension spring; 8. Battery; 9. Longitudinal suspension; 10. Drive and brake assembly; 11. Steer-by-wire assembly; 12. Tie rod; 13. Double wishbone suspension; 14. Front suspension spring; 15. Steering knuckle; 21. Steering controller; 22. Steering actuator assembly; 31. Steering column; 32. Sensor assembly; 33. Motor; 101. Reducer; 102. Brushless motor; 103. Electromagnetic brake; 104. Magnetic encoder. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings.

[0023] like Figures 1-6 A smart mobility vehicle chassis includes a front frame 1, a drive-by-wire steering assembly 2, a steering wheel 3, a base frame 4, and a main frame 5. The steering wheel 3 is connected to the upper part of the drive-by-wire steering assembly 2 and the front frame 1 is connected to the lower part. The front end of the base frame 4 is connected to the front frame 1 and the rear end is connected to the main frame 5. A battery 8 is located under the main frame 5, and a rear suspension spring 7 is located behind the main frame 5. The rear suspension spring 7 is connected to a longitudinal suspension 9. A drive and brake assembly 10 is fixed in the longitudinal suspension 9 and connected to the wheel 6.

[0024] The wheel 6, rear suspension spring 7, longitudinal suspension 9, and drive and brake assembly 10 are integrated into a single unit design, which not only improves the performance of the vehicle's running system, but also greatly improves the efficiency of the assembly process and makes it more convenient for elderly users to operate.

[0025] The entire corner module assembly, including the longitudinal suspension 9 and the drive and braking assembly 10, is connected to the main frame 5 via the elastic bushing at the front end of the longitudinal suspension 9 and the high-strength kingpin, thus realizing the vehicle's running, braking, flexible suspension, and shock absorption system functions. This design means that the corner module assembly can be installed on the frame in a single step, greatly simplifying the final assembly process.

[0026] The drive and braking assembly 10 integrates a reducer 101, a brushless motor 102, an electromagnetic brake 103, and a magnetic encoder 104 sequentially along the power axis.

[0027] The reducer 101 adopts a multi-stage planetary gear transmission structure, which can achieve a large reduction ratio of more than 10:1. This design is specifically designed for the working conditions of driving large-size tires with small-power motors at low speeds. It can significantly amplify the output torque of the motor, ensuring that the vehicle has good starting, climbing ability and load adaptability, while maintaining a compact structure.

[0028] The brushless motor 102 uses a brushless motor as its power source, featuring high efficiency, smooth operation, and low noise, making it particularly suitable for applications requiring high comfort, such as mobility scooters for the elderly.

[0029] The braking clamping force of the electromagnetic brake 103 acts directly on the motor drive shaft, i.e., the input end of the reducer 101. This braking method can amplify the braking force to the wheel end through the drive reducer 101, requiring only a small braking clamping force to lock the wheel. The electromagnetic brake 103 and the brushless motor 102 are controlled collaboratively by the same corner module controller. This integrated control architecture enables drive commands and braking commands to be coordinated and responded to within milliseconds.

[0030] The magnetic encoder 104 monitors the precise angular position and rotational speed of the output shaft of the brushless motor 102 in real time, and feeds back the high-precision position signal to the angle module controller, providing a key data foundation for the precise torque control and speed regulation of the brushless motor 102.

[0031] The wheel hub of wheel 6 is connected to the output shaft of reducer 101 via six bolts in a surface contact manner. The six bolts are tightened in a crisscross pattern, and the tightening torque is controlled at [value missing]. The wheel 6 and the power brake shaft of the drive-brake assembly 10 are located on the same axis. This connection method allows the load and impact on the wheel 6 in all directions to be evenly transmitted to the main bushing of the reducer 101. The main bushing transmits the load to the reducer 101 housing through bearings. The six bolts evenly distributed around the circumference of the reducer 101 housing are connected to the longitudinal suspension 9 in a surface contact manner, which can effectively absorb load and vibration, disperse impact, and improve the overall mechanical life. The drive-brake assembly 10 passes through the cantilever of the longitudinal suspension 9, cleverly utilizing the space in the suspension. At the same time, this wraparound design can also reduce the impact of road bumps and flying stones, providing a certain degree of protection for the brushless motor 102.

[0032] The longitudinal suspension 9 has a lug at one end, and the rear suspension spring 7 is connected to the longitudinal suspension 9 at one end via an elastic bushing, while the other end is connected to a lug under the main frame 5. This design cleverly reduces the transmission of ground impact to the seat, greatly improving ride comfort, better protecting the lower back of elderly passengers, and reducing driving fatigue.

[0033] The longitudinally mounted suspension 9 is placed in the U-shaped opening of the main frame 5's mounting lug. Then, the high-strength kingpin passes sequentially through the hole on one side of the lug, the inner tube of the bushing, and the hole on the other side of the lug. Finally, the two ends of the kingpin are locked in place with nuts and cotter pins or self-locking nuts, completing the entire connection. The kingpin provides rigid support, ensuring structural stability. The rubber body inside the bushing absorbs road impacts and vibrations through elastic deformation and allows for slight torsion of the suspension, thereby significantly improving comfort and reducing noise.

[0034] The steer-by-wire assembly 2 is a purely electronic control system that completely eliminates any mechanical connection between the steering wheel 3 and the wheels 6. It consists of three core modules: an input module, a brain module, and an output module. Through precise collaborative work, it achieves reliable and accurate steering control.

[0035] The input module includes a steering wheel 3, a sensor assembly 32, and a motor 33. The input module serves as the driver's command input terminal, and its core is a force feedback steering wheel 3 integrating multiple sensors. The hardware mainly includes: The steering wheel 3 is structurally similar to a traditional steering wheel, but the steering column 31 below it only serves as a load-bearing structure and its end is not connected to any steering tie rod.

[0036] The sensing assembly 32 includes high-precision non-contact angle / torque sensors that are mounted directly on the steering column 31 to detect the absolute angle of the steering wheel 3, rotation speed, and torque applied by the driver in real time without delay.

[0037] Motor 33 is a high-performance brushless servo motor coupled to the steering shaft through a reduction gear mechanism. Motor 33 is responsible for generating precise resistance torque or assistance according to the instructions of steering controller 21, simulating a realistic steering feel for the driver, such as self-centering force and feedback on road bumps.

[0038] The brain module is a high-performance electronic control unit (ECU), which includes: Multi-core microprocessor: Possesses powerful computing capabilities and can process multiple signals from the steering wheel, vehicle bus, and other sensors, such as vehicle speed and yaw rate sensors, in parallel.

[0039] Complex control algorithms: The core software for implementing the steering function is embedded in the hardware, including a basic steering mapping algorithm that can convert the steering wheel angle into the target wheel angle; a variable transmission ratio control algorithm that changes the steering sensitivity with vehicle speed; a force feedback generation algorithm; and vehicle stability coordination control logic.

[0040] The output module uses motor 33 as the core drive element, and motor 33 is integrated inside the steer-by-wire assembly 2. This integration allows motor 33 to directly drive steering knuckle 15 through a precision transmission mechanism, completely replacing traditional mechanical connecting parts such as steering tie rods and steering knuckle arms, thus realizing true steer-by-wire functionality.

[0041] In terms of structural design, the double wishbone suspension 13 works in conjunction with the steer-by-wire assembly 2 to ensure precise wheel positioning and provide a fast and accurate steering response. The front suspension springs 14 are optimized and coordinate with the steering system to effectively improve ride comfort. The front frame 1, as the overall load-bearing structure, provides a stable mounting base for all subsystems.

[0042] like Figure 7 As shown, the workflow of the intelligent mobility scooter chassis is as follows: (1) Driving control Drive command: The driver operates the forward / reverse lever, and the signal is transmitted to the vehicle controller. The vehicle controller converts the lever signal into a motor speed command and sends it to the electric drive controller via the CAN bus.

[0043] Power output: The electric drive controller controls the brushless motor 102 of the rear wheel corner module to work according to the speed command, and drives the wheels through the planetary reducer.

[0044] Real-time feedback: The magnetic encoder 104 continuously monitors the motor speed to achieve precise control.

[0045] (2) Braking Management Normal braking: When the lever is released, the vehicle controller converts the rate of change of the lever release speed into a braking demand and sends it to the electric drive controller via the CAN bus. The electric drive controller then controls the integrated drive and braking assembly to implement motor deceleration, regenerative braking, or electromagnetic braking, depending on the demand.

[0046] Automatic parking: When the vehicle is parked, the drive and brake assembly will disengage the regenerative braking and activate the electromagnetic brake to put the vehicle in a mechanical parking state.

[0047] Emergency Release: When the main control circuit fails, the electromagnetic brake 103 cannot release normally. At this time, the backup circuit relay is activated, and the backup electromagnetic brake control circuit is enabled. The user can control the electromagnetic brake release via a switch.

[0048] (3) Steering control Human-driven steering perception: When the steering wheel 3 is turned, the angle sensor integrated in the steering wheel 3 detects the steering intention and converts it into steering angle and angular velocity signals, which are sent to the vehicle controller via the CAN bus.

[0049] Intelligent processing: The vehicle controller determines the steering information to be executed based on the vehicle's driving mode, judging whether it is human-driven steering from the steering wheel sensor or autonomous driving steering from the autonomous driving controller, and sends the steering angle, angular velocity, etc. to the steering controller of the steer-by-wire assembly.

[0050] Steering execution: The steering controller 21 calculates the optimal steering angle based on comprehensive vehicle speed and other information, and controls the steering motor to drive the wheels to deflect.

[0051] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A smart mobility scooter chassis, characterized in that, It includes a front frame (1), a steer-by-wire assembly (2), a floor frame (4), and a main frame (5); the steer-by-wire assembly (2) is connected to the steering wheel (3) above and the front frame (1) below; the floor frame (4) is connected to the front frame (1) at the front end and to the main frame (5) at the rear end; the main frame (5) has a battery (8) below and a rear suspension spring (7) at the rear; the rear suspension spring (7) is connected to the longitudinal suspension (9); the drive and brake assembly (10) is fixed in the longitudinal suspension (9) and connected to the wheel (6).

2. The intelligent mobility scooter chassis according to claim 1, characterized in that, The drive and brake assembly (10) integrates a reducer (101), a brushless motor (102), a magnetic encoder (104), and an electromagnetic brake (103) in sequence along the power axis. The wheel (6) and the output shaft of the reducer (101) are connected by surface contact.

3. The intelligent mobility scooter chassis according to claim 1, characterized in that, The reducer (101) is a multi-stage planetary gear transmission structure with a reduction ratio greater than 10:

1.

4. The intelligent mobility scooter chassis according to claim 1, characterized in that, The steer-by-wire assembly (2) includes an input module, a brain module, and an output module.

5. The intelligent mobility scooter chassis according to claim 1, characterized in that, The longitudinal suspension (9) has a lug at one end, and the rear suspension spring (7) is connected to the longitudinal suspension (9) at one end through an elastic bushing, and the other end is connected to the lug under the main frame (5).

6. The intelligent mobility scooter chassis according to claim 2, characterized in that, The braking clamping force of the electromagnetic brake (103) acts on the drive shaft of the brushless motor (102), and works with the brushless motor (102) to achieve deceleration, regenerative braking or mechanical parking braking.

7. The intelligent mobility scooter chassis according to claim 2, characterized in that, The magnetic encoder (104) is directly mounted on the output shaft of the brushless motor (102) and is used to collect the angular position and rotational speed data of the brushless motor (102).

8. The intelligent mobility scooter chassis according to claim 4, characterized in that, The input module includes a steering wheel (3), a sensor assembly (32), and a motor (33).

9. The intelligent mobility scooter chassis according to claim 4, characterized in that, The output module uses a motor (33) as the core driving element, and the motor (33) is integrated inside the steer-by-wire assembly (2).

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