Precision Of Drilling Research Articles

Feasibility and accuracy of orthopaedic surgical robot system for intraoperative navigation to locate bone tunnel in anterior cruciate ligament reconstruction.

The combination of navigational system and robotics has the potential to accurately identify and drill bone tunnels in anterior cruciate ligament (ACL) reconstruction. This study explores the feasibility and accuracy of bone tunnel positioning using the TiRobot, an orthopaedic surgical robot. The experiment was divided into two groups. In group A, the bone tunnels were positioned using the TiRobot surgical robot (n=8). In group B, handheld locators were used for positioning (n=8). TiRobot can be used for positioning the ACL bone tunnel. The accuracy of positioning the femoral tunnel in group A and B was 1.00±0.20 and 3.10±0.59mm, respectively (t=-9.49, P<0.001). As for tibial tunnel, the accuracy was 1.02±0.20 and 2.64±0.14mm, respectively (t=-18.54, P<0.001). The bone tunnel drilling precision using TiRobot for ACL reconstruction surgery was more accurate than traditional surgical techniques.

A 3D printed cast for minimally invasive transfer of distal radius osteotomy: a cadaver study

PurposeIn corrective osteotomy of the distal radius, patient-specific 3D printed surgical guides or optical navigation systems are often used to navigate the surgical saw. The purpose of this cadaver study is to present and evaluate a novel cast-based guiding system to transfer the virtually planned corrective osteotomy of the distal radius.MethodsWe developed a cast-based guiding system composed of a cast featuring two drilling slots as well as an external cutting guide that was used to orient the surgical saw for osteotomy in the preoperatively planned position. The device was tested on five cadaver specimens with different body fat percentages. A repositioning experiment was performed to assess the precision of replacing an arm in the cast. Accuracy and precision of drilling and cutting using the proposed cast-based guiding system were evaluated using the same five cadaver arms. CT imaging was used to quantify the positioning errors in 3D.ResultsFor normal-weight cadavers, the resulting total translation and rotation repositioning errors were ± 2 mm and ± 2°. Across the five performed surgeries, the median accuracy and Inter Quartile Ranges (IQR) of pre-operatively planned drilling trajectories were 4.3° (IQR = 2.4°) and 3.1 mm (IQR = 4.9 mm). Median rotational and translational errors in transferring the pre-operatively planned osteotomy plane were and 3.9° (IQR = 4.5°) and 2.6 mm (IQR = 4.2 mm), respectively.ConclusionFor normal weight arm specimens, navigation of corrective osteotomy via a cast-based guide resulted in transfer errors comparable to those using invasive surgical guides. The promising positioning capabilities justify further investigating whether the method could ultimately be used in a clinical setting, which could especially be of interest when used with less invasive osteosynthesis material.

Vision Based Navigation for Omni-directional Mobile Industrial Robot

In this paper, an Omni-directional mobile industrial robot drilling system for aerospace manufacture is introduced. Mecanum wheels are used for the robot's maneuverability in congested workspace. An industrial robot is applied to complete the drilling work for a rocket shell. A vision system is applied to enhance the precision of mobile drilling. Additional sensor systems such as laser measurement system and displacement measurement system are equipped to do the autonomous navigation and anti-collision job. To increase the flexibility and working volume of the mobile industrial robot, the autonomous mobile drilling scheme is presented. In order to fulfil the requirement for drilling precision in aerospace industry, a vision-based deviation rectification solution is developed. Some experiments are carried out to compare the influence of different calibration targets on the robot system. Numerical tests show that the rectification system is able to satisfy the accuracy of the positioning in the autonomous drilling work.

Vibration Tests of the Processing Shaft Cascading Structure in High Speed and High Precision PCB Drilling Machine

It is necessary to study the dynamic characteristics of the structure of processing shaft cascade in high speed and high precision PCB drilling machine because of its great impact on the drilling precision. As a basic part, the dynamic characteristics of the structure of cascade depend on the dynamic characteristics of the Z-axis floor. Based on it, firstly, the free mode test is conducted on the Z-axis floor, the same as the modes that it is just set up on the guide rail, the cascade is added and the motor spindle has been added on the Z-axis floor. From the four situations, the modal pa-rameters are gained in the tests. Then the ODS test is carried out and the vibration is analyzed in the real situation. The vibration tests of the cascade comprehensively acquire dynamic characteristics from the Z-axis floor before being assembled to the Z-axis floor which is entirely cascaded on the Z axis. Acknowledge of the impact that the vibrations bring to the drilling precision of the drilling machine provides the direction of improving the structure.

Research on NC Electrochemical Mechanical Drilling

NC electrochemical mechanical drilling was based on NC, Electrochemical machining and mechanical grinding. It drilled with different diameter composite cathodes. This kind of drilling method took the advantages of electrochemical mechanical, so it was not restricted by parts’ strength, hardness and stiffness. The cover of cathode ensured the drilling precision. So this technology should be studied. This paper took 304 stainless steel and high temperature alloy GH710 to do study, at last the reasonable and high efficient process parameters were found in the experiment. The high quality holes of better roundness and small taper angle were drilled. The results showed that the study of NC electrochemical mechanical drilling difficult-to-machine materials was very meaningful.

Edge Distance Determination for Aeronautical Thin-Walled Structures with Automated Riveting

In the process of automated riveting, the position between the riveting head and the holes distributed on the stringer and wing skin to be riveted will go beyond the design requirements currently. Using the edge distance determination technology to measure and compensate the deviation in time is one effective method to solve this problem. In the dissertation, after the characteristic of the edge distance determination technology is introduced, the working principle of the edge distance tracer apparatus is developed. Based on the mechanical design solution, a pressure sensor is selected to measure the position relationship between the riveting head and the stringer. Then an edge distance tracer apparatus is struck out to detect the deviation, which is an automatic positioning feedback device that can be fit for many kinds of stringers. And the riveting head is operated to meet the design deviation requirements. By using this technology, the drilling precision of the automated riveting system can be effectively improved.

Small Hole EDM by Current Dividing Based on Discharging Area

A new EDM method of small hole is presented in which critical size of EDM drilling can be reduced less than that of limit of primitive EDM system by current dividing. The drilling characters of small hole EDM by means of current dividing based on a principle of discharging-area equalization were studied and discussed. The experimental results show that drilling speed and discharging gap decrease a little, and electrodes wear increases slightly. There is a drilling consistency in EDM ability between single and double electrodes under discharging-area equalization, and new method helps to improve the drilling precision. The research outcomes provide a deeper understanding for a small hole EDM.

Ultraviolet curing adhesive-based optical fiber feedthrough for ultrahigh vacuum systems

We present an inexpensive, simple, and robust method of making an optical fiber feedthrough for ultrahigh vacuum UHV systems. This system is particularly devoted for cold atom experiments. A drilled standard UHV DN16CF flange allows us to pass a fiber inside an UHV chamber. An optical ultraviolet UV curing adhesive is simultaneously used for holding the fiber through the flange and as a vacuum sealant. A vacuum down to 10−9 mbar is currently observed, while the optical insertion loss of the feedthrough is monitored and does not exceed 0.01 dB. In most of light-matter interaction experiments, laser light must pass through ultrahigh vacuum chambers. Although light beams can be propagated in free space through glass view-ports, more and more recent cold atom experiments use optical fibers to carry or collect light to or from a well defined area. This covers a wide variety of experiments such as atom-surface interactions or atomic samples guided inside hollow-core fibers. This kind of experiments requires continuous fibers through the vacuumatmosphere interface. A feedthrough for optical fiber based on a Teflon ferrule has been successfully demonstrated. However, this technique has several drawbacks. It requires a very high drilling precision, and as a consequence, must be accurately designed for a specific fiber diameter. As the ferrule must avoid any leaks, a constraint is applied to the fiber, which can induce birefringence and excess losses. Furthermore, as the polymer coating of the fiber ages under mechanical constraints, leaks might appear with time. We have developed a simple method to realize an optical fiber feedthrough completely free of those problems. It is based on a commercially available UV curing adhesive. The realization is easy and does not require accurate mechanical pieces. A multiple-fiber configuration is also achievable.

Heat Absorbing Rate in Laser Drilling of YG8 Alloy

Based on a principle of laser drilling size and the roundness copied with respect of laser spatial mode, heat absorbing rate for laser drilling of YG8 is presented in theory and application. The mathematical models are then developed. The relationship of heat absorbing rate compared to the original absorbing rate is thus derived that is A = T +A0. It shows that heat absorbing rate to laser beam increases linearly with drilling temperature. The research outcome is used to optimize preheating process in which the novel method improves laser drilling precision from 0.03mm of primitive laser system to 0.01mm under the condition of heat absorbing.

Intraoperative CT (iCT) with an integrated navigation system in a multidisciplinary operating suite for cerebral and spinal surgery

Core decompression by exact drilling into the ischemic areas is the treatment of choice in early stages of osteonecrosis of the femoral condyle. Computer-aided surgery might enhance the precision of the drilling and lower the radiation exposure time of both staff and patients. The aim of this study was to evaluate the precision of the fluoroscopically based VectorVision®-navigation system in an in vitro model.Thirty sawbones were prepared with a defect filled up with a radiopaque gypsum sphere mimicking the osteonecrosis. 20 sawbones were drilled by guidance of an intraoperative navigation system VectorVision® (BrainLAB, Munich, Germany). Ten sawbones were drilled by fluoroscopic control only.A statistically significant difference with a mean distance of 0.58 mm in the navigated group and 0.98 mm in the control group regarding the distance to the desired mid-point of the lesion could be stated. Significant difference was further found in the number of drilling corrections as well as radiation time needed.The fluoroscopic-based VectorVision®-navigation system shows a high feasibility and precision of computer-guided drilling with simultaneously reduction of radiation time and therefore could be integrated into clinical routine.

Precision of computer-assisted core decompression drilling of the femoral head

Osteonecrosis of the femoral head is a local destructive disease with progression into devastating stages. Left untreated it mostly leads to severe secondary osteoarthrosis and early endoprosthetic joint replacement. Core decompression by exact drilling into the ischemic areas can be performed in early stages according to Ficat or ARCO. Computer-aided surgery might enhance the precision of the drilling and lower the radiation exposure time of both staff and patients. The aim of this study was to evaluate the precision of the fluoroscopically based VectorVision navigation system in an in vitro model. Thirty sawbones were prepared with a defect filled up with a radiopaque gypsum sphere mimicking the osteonecrosis. Twenty sawbones were drilled by guidance of an intraoperative navigation system VectorVision (BrainLAB, Munich, Germany) and 10 sawbones by fluoroscopic control only. No gypsum sphere was missed. There was a statistically significant difference regarding the three-dimensional deviation (Euclidian norm) as well as maximum deviation in x-, y- or z-direction (maximum norm) to the desired mid-point of the lesion, with a mean of 0.51 and 0.4 mm in the navigated group and 1.1 and 0.88 mm in the control group, respectively. Furthermore, significant difference was found in the number of drilling corrections as well as the radiation time needed: no second drilling or correction of drilling direction was necessary in the navigated group compared to 1.4 in the control group. The radiation time needed was less than 1 s compared to 3.1 s, respectively. The fluoroscopy-based VectorVision navigation system shows a high feasibility of computer-guided drilling with a clear reduction of radiation exposure time and can therefore be integrated into clinical routine. The additional time needed is acceptable regarding the simultaneous reduction of radiation time.

Precision of computer-assisted core decompression drilling of the knee

Introduction Core decompression by exact drilling into the ischemic areas is the treatment of choice in early stages of osteonecrosis of the femoral condyle. Computer-aided surgery might enhance the precision of the drilling and lower the radiation exposure time of both staff and patients. The aim of this study was to evaluate the precision of the fluoroscopically based VectorVision®-navigation system in an in vitro model. Materials and methods Thirty sawbones were prepared with a defect filled up with a radiopaque gypsum sphere mimicking the osteonecrosis. 20 sawbones were drilled by guidance of an intraoperative navigation system VectorVision® (BrainLAB, Munich, Germany). Ten sawbones were drilled by fluoroscopic control only. Results A statistically significant difference with a mean distance of 0.58 mm in the navigated group and 0.98 mm in the control group regarding the distance to the desired mid-point of the lesion could be stated. Significant difference was further found in the number of drilling corrections as well as radiation time needed. Conclusion The fluoroscopic-based VectorVision®-navigation system shows a high feasibility and precision of computer-guided drilling with simultaneously reduction of radiation time and therefore could be integrated into clinical routine.

OPTIMUM DESIGN OF SMOOTH BLASTING IN HARD-ROCK TUNNELLING USING MANUAL DRILLING MACHINE AND ITS APPLICATION TO ACTUAL TUNNEL EXCAVATION

This study presents the formulation of an optimum design of smooth blasting using a manual drilling machine in hard-rock tunnelling and the cost estimation of overbreaking and underbreaking. The proposed design method aims to minimize the total expense of the extra concrete cost in the region of overbreaking and of the labour cost required to remove the unbroken rock in the region of underbreaking. The design variables is the collaring radius ΔR only. The calculated results indicate that the drilling precision of the look-out angle is the most important factor in the optimum design of smooth blasting in tunnelling, in the case of using a manual drilling machine. The results also indicate that 40% of the total expense can be saved by the improvement of drilling precision and the application of an optimum design.

OPTIMUM DESIGN OF SMOOTH BLASTING IN TUNNELLING HARD ROCK

This study provides the result obtained by an optimum design method of smooth blasting in tunnelling hard rock. The proposed design method aims at minimize the total expense of the extra concrete cost in the region of overbreak and the labour cost required to remove the unbroken rock in the region of underbreak. The design variables are the look out angle θ and the collaring radius R. The constraint of look out angle is set in order to provide the workability of the drilling. The overbreak and underbreak distributions used in the present study are the testing results obtained from Shiwa tunnel in Sanyo Highway. The calculated results indicate that the look out angle needs only the minimum values which satisfy the workability of the drilling and that the optimum collaring radius depends on the drilling precision. The results also indicate that the improvement of drilling precision can save 7-10% of the total expense and the optimization of the design can save 6-11% of the expense.

SMOOTH BLASTING IN HARD GRANITE TUNNEL USING AN AUTOMATIC DRILLING MACHINE

In this study, the smoothblasting in hard granite tunnel was discussed with reference to the results of three field tests which aimed at the minimization of overbreak and underbreak. In the tests, the drilling was practiced by the aid of automatic drilling machine. Among many factors which effect on the smooth biasting result, particular attention was payed to the drilling precision. Differences between the designed and actual blasted faces were statistically analized and smooth blasting results were discussed from its point of view.The study revealed that not only the blasting techniques but also the drilling precision give a great effect on the smooth blasting result in hard granite tunnels.