What are Useful Arm Vibrato Exercises for Violin Practice?

[RemiRemi]

Here's an exercise that I've found helpful: 1. Position the violin on your shoulder. 2. Place the thumb and first finger on the violin strings. 3. Apply light pressure with your first finger and bow on the strings. 4. Start rolling your arm, creating a pulsing effect. 5. Repeat this process , gradually increasing your speed.