 HAVNOP is a motorized shape-changing knob interface designed to deliver both four-speedback and safe sensations. The motivation is to improve cast performance in the limited vision by campaigning formation to users through haptic tubes. Dynamic four-speedback is generated by the DC motor while six several driven expandable fins create reliable shape sensations. At least six unique shape configurations can be transformed from the default cylindrical knob shape. Several fundamental four-speedback features have also been developed now demonstrating three options with GUI. A switch rendering a virtual bump between two virtual walls. A dial rendering six evenly spaced indents. A damper bearing rotational resistance with rotational speed.