BB - series The BB - series , also known as the BB unit , was a model of astromech droid active during the era of the Cold war , featuring a spherical body that allowed the droid to roll in any direction , with a head usually atop the body but not meant to be permanently physically attached to it ( which would inhibit the droid ' s ability to roll around ) . Like earlier astromechs , the BB unit could fit into the droid socket of a starfighter . One notable BB unit was BB - 8 , owned by Poe Dameron , who assisted with the recovery of a map to Luke Skywalker . Description . The BB - series was a model of astromech droid . Powered by a selenium drive , these droid s had an internal orbiculate motor that allowed their spherical bodies to roll across a variety of terrain , keeping their domed heads fixed on top with magnetic casters . Rather than keeping the head tethered by a single contact point , wireless telemetry allowed the two sections of the droid to communicate . The internal gyroscopic propulsion system was self - correcting , and surface sensors on the spherical body allowed the droid to travel across uneven environments such as desert s , with the benefit of its shell being sealed from dust contamination . For areas that proved too difficult for the orbiculate motor to traverse , BB units were equipped with compressed liquid cable launcher s that could tether and reel the droid in to hard - to - reach spots . As the droid ' s body faced in all directions at all times , it needed only to accelerate rather than turn . The BB ' s dense shell featured six swappable circular tool - bay disk s that could be fitted with numerous forms of equipment , such as a magnetic - tipped bolt - spinner . The droid ' s domed head was composed of a lightweight cranial frame featuring a large , round primary photoreceptor and a smaller articulated holoprojector array . The droid ' s sensors featured advanced calibrated synthetic optics . Transmitter and receiver antennae extended from the top of the head , and data ports were located above a band of stainless inoxium girding the bottom of the dome . The head could be dislodged from the body given significant force , but could quickly reattach itself with the magnetic casters . BB units possessed a dedicated , goal - focused personality , and were protected by self - preservation protocols . However , it was known for some experienced droids to create strong loyalty subprograms that saw them enter into dangerous situations in order to assist their masters and owners . The droids communicated via droidspeak variants of the most common astromech language . BB units also possessed a thermal hyperscan vindicator . History . The BB - series was an evolution of ball - shaped droids used near the end of the Galactic Civil War , such as prototype therapy droid s like QT - 9 , who saw service assisting New Republic veterans on Hosnian Prime following the Battle of Endor . This knee - high droid rolled on a blue - and - gold body with a square head balanced on top . The BB - series saw service during the latter years of the New Republic , and some were utilized by General Leia Organa ' s Resistance . This unit was considered a new - model astromech as of the time of the Attack on Tuanul in 34 ABY . Like the older and larger astromech models that preceded it , the BB unit was compatible with the astromech socket of starfighter s such as the T - 70 X - wing fighter , and was equipped to control on - board flight and power distribution systems . BB - 8 served as the trusty companion of Resistance pilot Poe Dameron , who fostered deep respect for his droid companion and kept BB - 8 ' s systems and components up - to - date and well maintained . Although the droid ' s self - preservation protocols made the droid somewhat skittish and easily frightened , his experiences created a strong loyalty subprogram that caused BB - 8 to follow Dameron into numerous dangerous situations .