Braking stability test of mobility scooters for the elderly: the guardian of safe travel

Braking stability test of mobility scooters for the elderly: the guardian of safe travel
In today’s society, with the aging of the population, mobility scooters for the elderly have become one of the important means of transportation for many elderly people. The elderly three-wheeled mobility scooter, with its unique three-wheel structure, has a certain degree of stability and flexibility, and is favored by many elderly people. However, safety is always the first priority of travel. Braking stability, as one of the important indicators for measuring the safety of mobility scooters for the elderly, is directly related to the life safety of the elderly during use.

1. The necessity of braking stability test
Ensure the life safety of the elderly: The physical functions of the elderly are relatively weak, and their reaction speed may not be as agile as that of young people. When encountering emergencies, such as pedestrians or obstacles suddenly appearing in front, the vehicle needs to be able to stop quickly and smoothly. Good braking stability can ensure that the elderly will not skid, lose control, or other dangerous conditions when the vehicle is in emergency braking, thereby ensuring their life safety to the greatest extent.
Improve driving comfort: Frequent emergency braking or vehicle instability during braking will seriously affect the riding comfort of the elderly. Through the braking stability test, the braking system of the vehicle can be optimized, the braking process can be smoother and smoother, the vehicle shaking and bumping can be reduced, and a comfortable and safe driving environment can be provided for the elderly, which can improve their satisfaction and use experience of the mobility scooter.
Meeting market demand and regulatory requirements: With the continuous development of the mobility scooter market for the elderly, consumers are paying more and more attention to product quality and safety performance. At the same time, local governments are also gradually strengthening the management of mobility scooters for the elderly and issuing relevant regulations and standards. Conducting braking stability tests can help companies ensure that their products meet market demand and regulatory requirements, improve the market competitiveness of their products, and avoid legal risks and market elimination due to quality problems.

2. Main contents of braking stability test
(I) Braking distance test
Braking distance on horizontal road: On a dry, flat horizontal road, let the elderly three-wheeled mobility scooter run at maximum speed, then fully step on the brake pedal and measure the distance from the start of braking to the complete stop of the vehicle. This test can intuitively reflect the braking ability of the vehicle under optimal road conditions and is one of the basic indicators for evaluating braking performance. Generally speaking, the braking distance of qualified elderly scooters on horizontal roads should be as short as possible to ensure that they can stop quickly in an emergency.
Ramp braking distance: In addition to horizontal roads, ramp braking distance testing is equally important. Place the vehicle on slopes of different slopes and perform uphill and downhill braking tests respectively. When going uphill, the vehicle needs to overcome the influence of gravity, and the braking system needs to provide sufficient braking force to prevent the vehicle from sliding backwards; when going downhill, the vehicle will accelerate downhill due to gravity. Testing the downhill braking distance can test the ability of the braking system to control the vehicle’s deceleration and stop. Through the ramp braking distance test, we can have a more comprehensive understanding of the braking performance of the vehicle under different road conditions, especially for those elderly scooters that often need to travel on sloped roads. This test result has important reference value.
(II) Braking stability test
Straight braking stability: Brake the vehicle when it is driving in a straight line at a certain speed to observe whether the vehicle will deviate, skid or lose directional stability. During the braking process, the center of gravity of the vehicle will shift, the load on the front wheels will increase, and the load on the rear wheels will decrease, which may affect the stability of the vehicle. If the braking force of the left and right braking systems is not balanced or the suspension system of the vehicle is not adjusted properly, it is easy to cause the vehicle to deviate from its original driving direction, increasing the risk of accidents. The straight-line braking stability test is designed to ensure that the vehicle can maintain a stable straight-line driving posture when braking, so that the elderly can better control the direction of the vehicle during braking and avoid danger caused by vehicle loss of control.
Steering and braking stability: simulates the situation that the elderly may encounter when braking during driving, such as when turning at an intersection and suddenly find an obstacle in front and need to slow down or stop. Apply the brakes when the vehicle is turning at a certain speed to observe whether the steering performance and stability of the vehicle are affected. Good steering and braking stability requires that the vehicle can still maintain accurate steering response during braking, without oversteering or understeering, and the body must remain stable to avoid unstable conditions such as roll and skidding. This test is crucial to ensure the safety of the elderly in complex road conditions because it is closer to the various situations that may be encountered during actual driving.
(III) Braking coordination time test
Definition and importance: Braking coordination time refers to the time interval from the driver starting to step on the brake pedal to the maximum braking effect of the vehicle’s braking system. During this period, the vehicle continues to move forward under the action of inertia, so the length of the braking coordination time directly affects the length of the braking distance. For elderly three-wheeled scooters, due to the relatively slow reaction speed of their users, a shorter braking coordination time is needed so that braking force can be generated as early as possible in an emergency, shortening the braking distance and improving safety.
Test method: Professional testing instruments are usually used to measure the braking coordination time. By installing a sensor on the brake pedal to detect the action signal of the driver stepping on the pedal, and installing acceleration sensors and other equipment at key parts of the vehicle to capture information such as acceleration changes during the vehicle braking process, the braking coordination time can be accurately calculated. Generally speaking, the braking coordination time of a reliable scooter should be as short as possible to ensure that the braking system can respond quickly to the driver’s operation.

3. Standards and methods for braking stability testing
(I) Related standards
National standards: In my country, although there is no special and unified mandatory national standard for braking stability for elderly three-wheeled scooters, there are some relevant general standards for reference. For example, the GB/T 12996-2012 Electric Wheelchair standard specifies the braking performance of electric wheelchairs, including braking distance and hill-holding performance. These requirements and test methods can provide reference for the braking stability test of elderly three-wheeled scooters to a certain extent. In addition, some clauses in standards such as GB 3565-2005 Bicycle Safety Requirements, such as the requirements for the strength and reliability of the braking device, are also applicable to the braking system components of elderly scooters.
Industry standards and enterprise standards: Due to the rapid development of the elderly three-wheeled scooter industry, some industry associations or enterprises have also formulated their own standards to regulate product performance. For example, the elderly scooter industry associations in some places may formulate more detailed and strict elderly scooter braking stability standards based on local market conditions and usage environment, covering various models and usage scenarios. At the same time, some large elderly scooter manufacturers will also formulate enterprise standards to improve product quality and competitiveness. These enterprise standards are often further refined and optimized on the basis of national standards, and make clearer provisions on indicators and methods of braking stability testing.
(II) Test methods
Instruments and equipment: The braking stability test requires the use of a series of professional instruments and equipment to ensure the accuracy and reliability of the test results. Common test equipment includes braking performance tester, deceleration tester, non-contact speed sensor, side slip test bench, etc. The braking performance tester can accurately measure the braking force, braking distance, braking deceleration and other parameters of the vehicle during braking; the deceleration tester is used to monitor the deceleration change of the vehicle in real time to evaluate the braking effect; the non-contact speed sensor can accurately measure the vehicle’s driving speed and speed change during braking without direct contact with the vehicle tires; the side slip test bench is mainly used to test the lateral slip amount of the vehicle during braking, so as to judge the lateral stability of the vehicle.
Test site requirements: In order to ensure the repeatability and consistency of the test results, the braking stability test needs to be carried out at a site that meets specific requirements. Generally speaking, the test site should choose a flat, dry, clean, uniform hard road surface, such as a concrete road surface or an asphalt road surface, and the road surface adhesion coefficient is required to be uniform without obvious ups and downs and potholes. For the ramp braking performance test, a special test ramp with adjustable slope needs to be built, and the surface treatment and length of the ramp should also comply with the relevant standards. In addition, during the test, the interference of external environmental factors, such as strong wind, rain and snow, should be avoided as much as possible to ensure the accuracy of the test data.
Test steps: First, install, calibrate and debug the test equipment according to the test standard requirements to ensure that the equipment can work normally and accurately measure the relevant parameters. Then, adjust the elderly three-wheeled scooter to the specified test state, such as the vehicle’s load state, tire pressure, brake system preheating, etc., to ensure that the test results can truly reflect the actual braking performance of the vehicle. Next, perform the test operation according to different test items and requirements. For example, when performing the braking distance test, the driver accelerates the vehicle to the specified initial speed, quickly steps on the brake pedal, and starts the test equipment for data collection at the same time, recording the braking distance, deceleration change, braking time and other parameters of the vehicle from the start of braking to complete stop. After completing each test, organize and analyze the test data, evaluate and judge the test results according to the standard requirements, and judge whether the braking stability of the vehicle meets the requirements.

4. Factors affecting braking stability and optimization measures
(I) Braking system design
Braking force distribution: Reasonable braking force distribution is one of the important factors to ensure braking stability. In the design of the braking system of the elderly three-wheeled scooter, the braking force distribution ratio between the front and rear wheels or the left and right wheels should be accurately calculated according to the three-wheel structural characteristics and center of gravity distribution of the vehicle to ensure that each wheel can evenly bear the braking force during braking to avoid vehicle deviation or side slip due to uneven braking force distribution. For example, for a front-engine, rear-drive three-wheeled scooter, since the center of gravity of the vehicle is relatively far back, the braking force distribution of the rear wheels should be appropriately increased during braking to improve the braking effect of the rear wheels and prevent the rear wheels from locking and losing grip.
Brake type and performance: Different brake types have different braking performance characteristics. At present, common brake types include drum brakes, disc brakes, electromagnetic brakes, etc. Drum brakes have a simple structure and low cost, but they are prone to thermal decay during long-term or continuous braking, resulting in a decrease in braking force; disc brakes have good heat dissipation performance and high braking stability, but are relatively expensive and complex in structure; electromagnetic brakes have fast response speed and high control accuracy, but they also have high requirements for power supply and control system. When designing the braking system, the appropriate brake type should be selected according to the specific use requirements and cost constraints of the elderly tricycle, and the performance of the brake should be ensured to meet the braking stability requirements of the vehicle, such as sufficient braking force, good thermal stability, and reliable automatic adjustment function of the brake clearance.
(II) Vehicle structure and parameters
The center of gravity position of the vehicle body: The center of gravity position of the vehicle body has a significant impact on the braking stability of the vehicle. If the center of gravity of the vehicle body is too high, the vehicle is prone to tilt forward during braking, resulting in excessive load on the front wheels and the rear wheels leaving the ground, thereby affecting the steering performance and stability of the vehicle. At the same time, a higher center of gravity may also make the vehicle more prone to tilt or rollover under the action of lateral force, especially under complex working conditions such as turning braking. Therefore, when designing a three-wheeled scooter for the elderly, the center of gravity of the vehicle should be lowered as much as possible by reasonably arranging the positions of various components in the vehicle and optimizing the body structure, so as to improve the stability and anti-rolling ability of the vehicle.
Wheelbase and track: The wheelbase and track are important parameters that affect the stability of the vehicle. A longer wheelbase can increase the longitudinal stability of the vehicle, reduce the nodding phenomenon of the vehicle during braking, and improve the driving stability of the vehicle; a wider track helps to enhance the lateral stability of the vehicle and reduce the risk of the vehicle sliding or rolling under the action of lateral force. When designing a three-wheeled scooter for the elderly, the wheelbase and track should be appropriately increased on the premise of meeting the vehicle’s handling flexibility and passability to improve the braking stability of the vehicle.
(III) Tire performance
Tire friction coefficient: The friction coefficient between the tire and the road surface is one of the key factors that determine the braking distance and braking stability. The larger the friction coefficient, the greater the adhesion between the tire and the road surface, the greater the braking force that can be provided during braking, the shorter the braking distance, and the better the stability of the vehicle. Therefore, choosing tires with good grip performance is crucial to improving the braking stability of elderly tricycles. Generally speaking, the friction coefficient of low rolling resistance tires, high-performance summer tires, etc. is relatively high, but under different road conditions and weather conditions, the friction coefficient of tires will change. For example, on slippery roads, the friction coefficient will be significantly reduced. Therefore, when using a scooter, the elderly should choose the appropriate tire type according to the actual driving environment, check the tire wear regularly, and replace severely worn tires in time to ensure that the tires have good friction performance.
Tire pressure: Tire pressure has an important influence on the performance of the tire. Too low air pressure will increase the contact area between the tire and the ground. Although it can increase friction to a certain extent, it will also increase rolling resistance, increase the driving resistance of the vehicle, and affect the vehicle’s handling performance and fuel economy; and when braking, too low air pressure may cause the tire to deform too much, affecting the normal rebound of the tire, and thus affecting the braking effect. On the contrary, too high air pressure will reduce the contact area between the tire and the ground, reduce friction, increase the braking distance, and at the same time, the comfort of the vehicle will deteriorate. Therefore, keeping the tire pressure within the specified range is a necessary measure to ensure the normal performance of the tire and improve the braking stability.
(IV) Driver operating habits
Braking force control: When driving a three-wheeled scooter, the elderly should reasonably control the braking force according to different road conditions and driving speeds. During normal driving, avoid sudden braking, predict the road conditions ahead in advance, gradually increase the brake pedal force, and slow down and stop the vehicle smoothly. Sudden braking will not only increase the braking distance, but also cause a greater impact on the vehicle’s suspension system and braking system, affecting the stability and service life of the vehicle. In addition, the elderly should try to maintain uniform braking force when braking to avoid the vehicle from running or skidding due to uneven force.
Speed ​​control: Speed ​​is one of the important factors affecting braking distance and braking stability. When driving at high speed, the braking distance of the vehicle will increase significantly, and the braking stability will also be relatively poor. Therefore, when driving a scooter, the elderly should strictly abide by local traffic rules and speed limit requirements to avoid speeding. Especially in areas with complex road conditions and dense crowds, or in special sections such as turns and downhills, the speed should be appropriately reduced to ensure that there is enough time and distance to brake in an emergency to ensure driving safety.

5. Summary
As a key link in the safety performance evaluation of elderly three-wheeled mobility scooters, the braking stability test is of great significance for ensuring the travel safety of the elderly, improving driving comfort, and meeting market demand and regulatory requirements. Through rigorous testing of braking distance, braking stability, and braking coordination time, companies can gain an in-depth understanding of the braking performance of their products, identify potential problems, and optimize and improve them in a timely manner. At the same time, when purchasing elderly mobility scooters, consumers should also pay attention to the braking stability test results of the product and choose models with excellent braking performance to ensure that they are in good condition during use.In the future, with the continuous advancement of technology and the improvement of industry standards, the braking stability of three-wheeled scooters for the elderly is expected to be further improved, providing a safer, more reliable and convenient way of travel for the elderly.