The research moved from theory to practice with the design and construction of a large vertical drilling rig capable of drilling up to 6-inch diameter holes in large rock samples.  Over the years an extensive programme of the full-scale experiments was carried out using PDC and roller-cone drill-bits to drill various rocks ranging from sandstone, limestone and granite. The rig is well instrumented, allowing for real-time response monitoring of the dynamic behaviour of the system through a LabVIEW data acquisition system that includes measurements of Weight On Bit (WOB), angular velocity, frequency and amplitude of dynamic oscillations, Rate Of Penetration (ROP) and Torque On Bit (TOB).

Further developments resulted in the construction of a large-scale horizontal drilling rig, as shown opposite.  This rig was designed and built to enable full scale experimental studies under conditions which are closer to those in the real drilling process (rock type, fluid pressure, axial force). The rig is equipped with state-of-the-art instrumentation allowing real-time response monitoring through a LabVIEW based data acquisition system. In this rig, rotary speed, Weight-On-Bit, frequency and amplitude of dynamic force (RED) are fully controllable by the user through a computer interface and various type of rock samples and drill-bits can be used. The whole process is monitored through several cameras and strict safety measures are in place when the test rig is in operation.

A typical RED module is shown in this photograph, and when in operation the module is attached to the drill string just prior to the drill bit. Early designs of the RED module at the university used a magnetostrictive mechanism to axially activate the module.  This module proved to be effective in generating a highly controllable dynamic force at frequencies up to 700 Hz.  Subsequent developments of RED involved the design of a 6-inch diameter RED Mechanical Exciter. This new 6-inch mechanical exciter was manufactured and fully tested in-house. This mechanical actuator module can be driven by an electrical motor or a turbine and in the laboratory proved to be effective in generating a controllable dynamic force of frequency up to 400 Hz.

More recent research within the university has investigated the application of RED to coring. A series of coring experiments on sandstone and granite using diamond impregnated and polycrystalline diamond compact (PDC) bits were carried out on a specially designed vertical laboratory drilling rig. Improvements in penetration rates of up to 180% compared to conventional coring for the same drilling conditions were achieved.  All cores retrieved from the tests were found to be in good condition showing consistent diameters, generally smooth core surfaces and no evidence of fracturing or other visible core damage.  The preliminary finding from this research demonstrated that the RED coring technology can provide significant improvements in Rate-of-Penetration (ROP) compared to conventional coring, while maintaining a consistent core quality.