Aspects determine optimal physical attribute values for defining a grip form factor on a microfluidic grip panel of a digital pen as a function of a correlation of the optimal physical attribute values to an intended use of the digital pen, wherein the optimal physical attribute values include a width dimension, a surface texture attribute, and shape pattern attribute that is defined as a function of the width dimension; and drive the microfluidic grip panel into a grip form corresponding to the determined optimal physical attribute values during use of the digital pen by a user.