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In the article "Calculation and Evaluation of AGV Suspension and Braking Torque", we introduce how to calculate the inertial force, braking torque and the magnitude of positive pressure required on the steering wheel of the AGV car. Today we will introduce how to calculate and evaluate the braking distance of AGV during emergency braking.

Because we evaluate the movement distance of AGV after shooting the emergency stop button and after locking, we can analyze it in two stages, namely the reaction distance of the entire brake system after shooting the emergency stop button, and the sliding distance of AGV sliding due to the impact of inertia after locking. As shown in the figure below:

Let's discuss the reaction distance below. The reaction distance is the AGV small car displacement distance required by the control system after the emergency stop button is removed until the brake is completely locked. The key parameters include the running speed during emergency stop and the reaction time of the entire brake system. The following figure is the operating timing parameter diagram of a certain brand of brakes. We need to check the delay time of the brake when holding the brake according to the model used by the steering wheel.

If the power supply of the brake is controlled by the intermediate relay, the delay of the intermediate relay can be superimposed for tens of milliseconds or directly check the delay time in the manual of the actual intermediate relay. If it is directly controlled by the driver, it can be ignored. To evaluate the calculation example, we take the reaction time of the brake system of 100ms, that is, 0.1s, for evaluation. At the same time, assuming that the AGV car is urgently braking at 1m/s, the braking reaction distance of the AGV car is measured as:

Reaction distance = vt=1m/s*0.1s=0.1m

After the brake is completely locked, the sliding distance of the AGV car is related to the friction coefficient and deceleration between the wheel and the ground. If we assume that the comprehensive friction coefficient between the wheel and the ground is 0.2, the sliding distance is：

Sliding distance = v²/(2μg)=1*1/(2*0.2*10)=0.25m

The total braking distance of the AGV car is:

Braking distance = reaction distance + slip distance=0.1+0.25=0.35m

Summarize:

This paper introduces the braking distance calculation method of AGV. From the calculation process, it can be seen that the reaction distance in the emergency braking distance is positively correlated with the speed during braking and the delay of the entire braking system; the slip distance is positively correlated with the initial speed during braking and negatively correlated with the friction coefficient. The top priority is to analyze specific issues in your work. Please do not simply apply or take some content in the text out of context as your reference.