pit 27 for recirculation the bottom hole assembly 100 of the illustrated embodiment includes a logging while drilling lwd module 120 a measuring while drilling mwd module 130 a roto steerable system and motor and drill bit 105 the lwd module 120 is housed in a special type of drill collar as is known in the art and can contain one or a plurality of known types of logging tools it will also be understood that more than one lwd and or mwd module can be employed e g as represented at 120 a references throughout to a module at the position of 120 can alternatively mean a module at the position of 120 a as well the lwd module includes capabilities for measuring processing and storing information as well as for communicating with the surface equipment in the present embodiment the lwd module includes a pressure measuring device the mwd module 130 is also housed in a special type of drill collar as is known in the art and can contain one or more devices for measuring characteristics of the drill string and drill bit the mwd tool further includes an apparatus not shown for generating electrical power to the downhole system this may typically include a mud turbine generator also known as a u201c mud motor u201d powered by the flow of the drilling fluid it being understood that other power and or battery systems may be employed in the present embodiment the mwd module includes one or more of the following types of measuring devices a weight on bit measuring device a torque measuring device a vibration measuring device a shock measuring device a stick slip measuring device a direction measuring device and an inclination measuring device a particularly advantageous use of the system.