What is the reason why the cage in front of the wheelchair jumps up?

Check whether the tires are normal; Check whether there are loose screws; There are many possibilities to check whether the angle of the front wheel seat assembly is normal, such as insufficient tire pressure, too high or too soft tire top, too soft shock absorber, different hardness of the left and right shock absorbers, damaged wheel bearings, loose front axle screws, out-of-round rims or tires, bulging tires or aging rubber. Check whether the tires are normal and whether the screws are loose.