is defined relative to any fixed point such as the earth the information may additionally provide control information for the bha 120 and any biasing and steering mechanisms 132 136 the icis 104 manages the drillstring rotation control block 112 and the drawworks control block 108 the phase torque and speed of rotation of the drillstring is monitored and managed by the drillstring control block 112 information from the bha 120 can be analyzed by the icis 104 as feedback on how the management is being performed by the drillstring control block 112 various operations during drilling use the drawworks control block 108 for example removal of the drillstring the icis 104 manages operation of the drawworks control block 108 during these operations the bha 120 includes a downhole controller 124 an orientation or direction sensor 128 a bit rotation sensor 140 one or more biasing mechanism 132 and one or more steering mechanisms 136 a typical bha may have more control systems which are not shown in fig1 information is communicated to the bha 120 from the surface to indicate a preferred direction of the drill bit additionally use of biasing and steering mechanisms 132 136 can be generally controlled by the icis 104 but the downhole controller 124 controls real time operation of the biasing and steering.