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The design of a marine propeller is characterized by its complexity rather then its shortcoming of knowledge how to asses its performance. There are several constraints to satisfy and all are in a different field. The three major considerations are strength, performance (efficiency) and cavitation behavior. There is not a perfect design methodology for the engineer how to use the different analysis tools available to come to a final design. The process is in most cases an iterative one that ends with a satisfying design rather then an optimal design. Optimal in this case means optimal in the sense of the best compromise possible. The application of a multiobjective optimizer makes it possible to visualise the trade-off among different conflicting objectives to guide the engineer in making his compromise. Furthermore it gives more insight in the problem at hand. The goal of this thesis is therefore two-fold. First one is the implementation of a multiobjective optimiser to show what the gains are when an analysis tool can be turned into a design tool. The second one is to apply it and investigate what the trade-off is between cavitation performance and efficiency for a test case based on a container vessel. The implemented algorithm is the non-dominated sorting genetic algorithm (NSGA) which is currently used in many other practical design problems. Genetic Algorithms are in general robust but not very efficient when it comes to the number of design evaluations it has to do. The algorithm is able to give a good approximation of the trade-off with a good diversity among its solutions. The propeller is analysed by the lifting surface program ANPRO which has an extension to predict sheet cavitation and bubble cavitation at both sides of the blade. In the test case considered there were additional constraints for a minimum blade thickness, the avoidance of bubble cavitation and a maximum allowance of sheet cavitation at the pressure side. The algorithm is able to converge to a trade-off between the two conflicting objectives. The size of the population is chosen as 80 and the algorithm run for 300 generations. From statistical data of the average age of the individuals in the population, converge could be determined. The simulations were not able to converge completely but sufficiently enough to obtain an approximation of the Pareto front. The trade-off show a decrease from maximum efficiency of 4% while gaining a reduction of sheet cavitation at the suction side of 27%. The amount of reduction of efficiency was roughly the same for different test cases but the cavitation percentages showed more variation. The method showed to be sensitive to the interpretation of the cavitation data produced by the propeller analysis program ANPRO.

Prior work of network coding is mainly focusing on multicast traffic. In this thesis, we propose a new network coding based communication algorithm called Network Coded Flooding (NCF) which is related to network wide broadcast. This designed algorithm is an integration of network coding and one of the commonly used broadcasting techniques in wireless networks. In this thesis, we choose Probabilistic Flooding Algorithm (PFA) to integrate with network coding since it is a simple and robust flooding algorithm; it can be used in random wireless networks; it can work without any network topology information. As with PFA, NCF has a parameter of rebroadcast probability that controls packets’ rebroadcasts when receiving innovative packets. During the process of designing NCF, we also consider the issues how efficient network coding can achieve in a random wireless network even if the system process ability is low and available memory space is also limited. Therefore, the idea of generation is used and we also propose a specific generation management method in this thesis that is able to let system occupy little system memory space while good network performance (such as successful packet delivery, low packet delay and great energy savings) and relatively low system process complexity are guaranteed. NCF is a practical network coding based flooding algorithm that can be used in random wireless networks; that does not need any network topology information; that huge amount of data is allowed to be transmitted during the communication process; that the requirements of buffering and network process ability are at a relatively low level. We simulate such algorithm in Network Simulator 2 (NS2), and the simulation results show that NCF can realize the benefits in terms of reliability, working efficiency and energy saving if related parameters (such as generation size or maximum number of generations per node has ) of NCF are set accurately. In addition, reasonable trade-off schemes are also given through analyzing the obtained simulation results, which give general ideas about how to accurately use and change the related parameters of NCF in order to efficiently balance the relationship between network requirements and network performance.

The fields of static balancing and tensegrity structures are combined into statically balanced tensegrity mechanisms. This combination results in a new class of prestressed structures that behave like mechanisms: although member lengths and orientations change, they can be deformed into a wide range of positions, while continuously remaining in equilibrium; in other words, the structures have zero stiffness. The key to these structures is the use of zero-free-length springs as tension members. The tools of structural engineering were used to search for, and understand, zero-stiffness modes in the tangent stiffness matrix of prestressed pin-jointed bar frameworks. To this end the recently uncovered parallels between structural engineering and mathematical rigidity theory were exploited. Mathematical literature described that affine transformations preserve the equilibrium of a tensegrity structure; these findings gained value when translated from a mathematical concept into the engineering terms rigid-body motions, shear and dilation. Not only did these transformations prove to be instrumental for describing zero stiffness, but it also provided new insight in the form-finding methods for tensegrity structures: the minimum nullity requirement for the stress matrix is formed by the affine transformations. In this research it was shown that affine transformations of the structure that preserve the length of conventional members are zero-stiffness modes valid over finite displacements: these are statically balanced zero-stiffness modes. What is more, for prestress stable structures with a positive semi-definite stress matrix of maximal rank -- meaning there are only affine transformations in its nullspace -- those are the only possible zero-stiffness modes. The length-preserving affine transformations exist if and only if the directions of the conventional members lie on a conic at infinity. If all conventional member directions lie on a conic, the number of independent length-preserving affine transformations can then be found with a simple counting rule. A systematic analysis of the zero-stiffness modes in the tangent stiffness matrix of a prestressed pin-jointed bar framework yielded several interesting scenarios that warrant further attention, as they cannot be fully described within the currently developed framework. Finally, a demonstration prototype was designed and constructed to illustrate the properties of statically balanced tensegrity mechanisms; the prototype serves as a proof of concept, not as a practically applicable design. Prior to construction, the range of motion of the tensegrity used for the prototype was extensively analysed using the analytic equilibrium conditions. The results were instrumental in dimensioning the prototype.

The role of cerebral white matter in intact brain functioning in older age is increasingly being recognized. Recent magnetic resonance (MR) imaging advances enable to non-invasively quantify structural integrity of normal appearing white matter. Studies into white matter integrity in the general elderly population, aim to gain insight into the pathophysiology of cognitive decline and neurodegenerative diseases such as dementia. Tract Based Spatial Statistics (TBSS), a novel analysis technique, allows the automated analysis of microstructural integrity in the tract centres of cerebral white matter. Fractional anisotropy images, derived from Diffusion Tensor MR data for every subject, are spatially normalized in a constrained manner. Subject specific measurements are then projected onto a skeleton of the common white matter structures to allow comparison of measurements between subjects. A feasibility study using TBSS was conducted in a small subject group. This study helped identify methodological components that needed adaptation or extension in order to analyse Tract Based Spatial Statistics of the normal appearing white matter in the general elderly population. In order to best drive the registration in the first stage of TBSS, a study specific template was established by crosswise registering all subjects' fractional anisotropy images. The time required for this operation was reduced by the adoption of a hierarchical registration scheme. To allow a specific focus on the normal appearing white matter, and thus to exclude visibly abnormal white matter, we used an existing white matter lesion segmentation. Once maps of white matter lesions were transformed into the subjects native space, we projected these maps onto the skeleton to earmark skeleton voxels originating in white matter lesions for subsequent exclusion in the statistical analysis. Furthermore, brain masking was improved, laterality is ascertained to be consistent between the different image processing pipelines and the followed TBSS pipeline was transformed to allow a large epidemiological cohort (N=832) to be processed. The latter modifications include adaptations to enable nonparametric permutation based multiple comparison correction in conjunction with a clustering approach. This thesis mainly addresses the methodological extensions and adaptations implemented to allow the proposed analysis. A manuscript "White matter atrophy and lesion formation explain the loss of structural integrity of white matter in aging" is included in Appendix 2. This manuscript, accepted for publication in NeuroImage, introduces the adaptations and extensions, but most importantly describes the application of the developed methodology and the conclusions that can be derived from the obtained results. The successful application of the adapted methodology offers numerous opportunities for future research. The aggregation of tract-specific measures derived from diffusion tensor MR images into imaging based biomarkers for early diagnosis of neurodegenerative diseases can be investigated. A first start will be made in studying the cingulate bundle. Another future direction is to define local measures to describe lesion load or white matter atrophy. This would yield insight into the link between macrostructural white matter changes, lesion formation and atrophy, and microstructural properties derived with diffusion tensor MR.

This study describes a method for the identification of Time-Varying joint admittance. The method transforms the time signals into a time--frequency representation using the wavelet transform, from which the Time--Varying frequency response function (TV--FRF) is estimated, and the model parameters are derived. Analysis of the performance of the developed method is established by simulation of the human arm. The study showed that increasing the observation time, increase the confidence regions of the estimate. The study showed that smoothing is needed, but it comes with a trade-off between precision and response time. Increasing the time smoothing increases the precision but decreases the response time. The developed method showed promising results by estimating the properties of the simulated model, giving the bases for a posterior study using experimental data.

The micro milling process is one of the micro manufacturing processes that have the potential to achieve relative accuracies in the range of 10-3 to 10-5. To conduct scientific research an xxperimental micro milling setup has been designed. Prior to do any kind of research it is required to find out what the contribution of the machine tool to the accuracy of a work piece is and therefore the accuracy of the micro milling setup will be evaluated in this thesis. To evaluate the accuracy of the micro milling setup the volumetric error is introduced and defined as: The volumetric error is the difference between the nominal location of the tool and work piece relative to the machine tool reference frame and the actual location relative to the machine tool reference frame. The actual location of the tool and work piece is the result of the twenty-one geometrical errors. The main question this Masters Thesis research answered was: What is the accuracy of the micro milling setup in terms of the volumetric error which results from geometrical errors? To answer this question two main goals are defined. The first goal is to derive an analytical model of the micro milling setup that calculates the volumetric error as a function of the twenty one independent geometrical errors. This analytical model is called the kinematics error model and calculates the volumetric error as the difference between nominal position of the tool relative to the workpiece and the actual position of the tool relative to the work piece. The kinematics error model calculated a range for volumetric errors that in X direction ranged from -3.87 μm to 8.67 μm and in Y direction the volumetric errors ranged from -2.86 μm to 8.27 μm. Furthermore the kinematics error model revealed that the volumetric error is most sensitive to the geometrical errors of the X stage. The arms attached to the X stage that convert the rotational errors into translational errors are the largest in magnitude. The second main goal is to perform experiments that verify the model. The model has been verified with experiments and it turned out that towards the end of travel of the stages the the measured volumetric error lied outside the calculated range of the volumetric error. The model calculated a better precision. The measured volumetric errors varies between -1.32 μm and 9.64 μm in X direction and in Y direction between -6.60 μm and 1.36 μm. To find an explanation for the observed differences the influence of other sources of error on the measurement result is studied. Results found in literature suggest that the difference between the model and the measurements has to be attributed to the influence of heat that originates from mechanical and electrical components in the stages. The observed increase in the measured hysteresis in X direction and Y direction and the increase in the measured position error in X direction indeed hint at the influence of heat on the experimental results. Therefore a small experiment was conducted in which the temperature was measured whilst a circular interpolation test was repeatedly performed. This experiment however could not confirm the influence of heat on the experimental results. Results found in literature and the experiment performed however clearly revealed that the influence of heat is the most likely explanation for the observed differences. The influence the heat has on the volumetric error should be further investigated and should be minimized. The accuracy of the micro milling setup will however never be better than the accuracy that was obtained with the kinematics error model.

Eight healthy young adult males seated in a rigid chair and restrained by a five point harness belt underwent anterior-posterior random appearing multisine perturbations with a frequency range of 0.3-20 Hz. Six different conditions were tested differentiating in maximum acceleration level ([1;2;4;8] m/s²) and in task (mental arithmetic and blindfolded). The head and neck kinematics were captured by a Qualisys motion capture system and Xsens accelerometers. Muscle activity of the trapezius and sternocleidomastoid muscles was collected by a Delsys EMG system. A two pivot neck model was developed representing the head-neck kinematics separating upper and lower neck kinematics. The kinematics were described with an error margin of 2.5 % of the maximum range of motion of the head. The amount of neck deformation relative to the perturbation is expressed in gain and phase, the linearity is expressed in squared coherence. For the head-neck kinematics a significant (P < 0.05) increase in gain was found for decreasing acceleration levels, indicating non-linearity of the human reflexes and/or the passive neck mechanics. At lower frequencies, the mental arithmetic task resulted in a 9 % decrease of neck deformations (P < 0.01). At lower frequencies, blindfolding resulted in a 16 % increase of neck deformations (P < 0.05). The pivot rotations showed for low acceleration levels similar gain and phase characteristics for both the upper and lower pivot up to 3 Hz. Increasing acceleration levels resulted in a major decrease of relative upper neck deformations (P < 0.05) and an increase of relative lower neck deformations (P < 0.01), suggesting different control strategies for both pivots. For frequencies above approximately 5 Hz an increasing phase lag up to 180º for the upper pivot with respect to the lower pivot is found, indicating C-shaped neck bending for low frequencies and S-shaped neck bending for high frequencies. With the exception of the upper pivot response the squared coherence showed globally values above 0.5 between 1-12 Hz.

One of the main methods of oil and gas transport at sea is performed by pipelines from the well or a platform offhore to another offshore structure or to land. Allseas is a company capable of installing these pipelines under various challenging operating conditions. In today's market, competition and oil and gas availability make it necessary for Allseas to operate at the top of capability. For each project, calculations are performed beforehand to ensure a vessel will be able to deal with the pipeline installation under the specified conditions. When laying pipe in deep water, the longitudinal force required to hold the pipe can go up to 1000 mT. It is found that the calculations performed to predict this force do not always correspond with reality. The process of laying pipe involves transporting pipe over rubber coated rollers to the seabed under high tensions. The contact between the pipe and the rubber coated rollers cause a rolling resistance, which is not yet included in calculations, possibly explaining (part of) the discrepancy between calculations and reality. The goal of this thesis was to determine the amount of rolling resistance caused by the contact between the rollers and the pipe when transporting the pipe to the seabed. A literature study was performed leading to an analytical model based on material properties. Furthermore, a test setup was built where rolling resistance was measured. The results of the analysis and tests have been analyzed and related to actual operating conditions. It showed that the rolling resistance is much less than currently used in practice. From these results recommendations were provided on how to further develop the acquired analytical and material models which are used for calculating rolling resistance. The research was based on Allseas' vessel 'Solitaire', the world's largest pipe lay vessel but the results can be applied to all vessels having rubber coated rollers.

Meniscectomy is a medical procedure where ruptured meniscal tissue is removed within the knee joint. The con- ventional cutters fail to reach the entire meniscus. Therefore, the focus of this study is to create a cutter with a steerable tip, which allows sideway steering to increase the reacha- bility within the knee joint. Additionally, this steerable joint is required to be robust to transmit a cutting force of up to 190N. The mechanism design is divided into the functions: steering and actuating cutting mechanism. The most promis- ing solution of each function was combined and resulted in the use of a crossed configuration of a Compliant Rolling- Contact Element for the instrument joint. Flexural Steering Beams actuate the rotation of the joint using the principle of a parallelogram mechanism. A prototype of this mechanism has a range of motion of +25 and -22 degrees with a steering stiffness at the handle side of 18Nmm/rad. An axial load of 200N on the tip corresponded with a parasitic deflection of 4 degrees. This unique type of a steerable joint shows poten- tial to be functional in a meniscectomy cutter due to its great robustness towards compression, yet allowing the instrument tip to deflect.

Blood flow and the associated shear forces have important biological effects on blood vessels. It has been suggested that blood flow abnormalities play a part in the development and the rupture of a deformed part of the wall of a brain artery, which is called an intracranial aneurysm, and thus in cerebral hemorrhages. Knowledge about the blood flow velocities and profiles in patient’s aneurysms is of major importance to understand their effect on the blood vessels. The Amsterdam Medical Center obtains blood flow velocities and profiles in the aneurysm region with a measurement technique called phase contrast MRI. There is a need for a validation of the measurement technique and protocol of the Amsterdam Medical Center. A common way of validation is the use of a flow phantom which is, in this case, a physical model of the circulation in the region of an aneurysm. In this project, the flow velocities and profiles in the aneurysm phantom are measured with phase contrast MRI and with Particle Image Velocimetry. The results of both measurement techniques are compared in order to contribute to the validation of blood flow measurements in intracranial aneurysms with phase contrast MRI.

In order to understand how the different brain systems work, control theory concepts are used to represent the input - output relationships of the structures involved. Perturbations is a common tool to study and analyze a control system. One example of a brain circuitry is the oculomotor system. Although, visual perturbations have been used to perturb the eye no mechanical perturbations have been applied up to now. Mechanics is the only way to evoke an unexpected movement, which is an essential factor to motor control. In this study, a magnetic actuator is designed to be used to apply torques in the rabbit eye. In vitro experiments were conducted in a prototype, which roughly mimics the movement of the eye in the horizontal plane, to test the function of the actuator. Experiments in the rabbit (in vivo) were also performed. In vitro results showed that the conceptual design is sound and the demanded torque of 17 mN mm was achieved. During preliminary in vivo results, clear eye movements were recorded as a result of the actuator's perturbations. The actuator designed enables a series of experiments in the frame of oculomotor control research.

In this paper, stepping over a zero height obstacle with minimal actuation is studied for a limit cycle walker modeled as a double inverted pendulum. The obstacle position is estimated by stereo vision. Actuation is realized by a constant torque per step on the hip and a push-off collinear to the trailing leg. Stepping over the obstacle must be accomplished with the obstacle position exactly on a predefined position in between the legs with the final state right after push-off being equal to the initial state. Thus, at least two steps must be taken to perform this task, such that the first step is used to make sure the relative position of the obstacle is correct. In the best case scenario, the obstacle is exactly in between the legs during a nominal walk. In that case, actuation does not have to be adjusted with respect to the nominal actuation. In the worst case scenario the obstacle is exactly at a stepping position. In that case, a translation of the step positions is needed. For stepping over in two steps this is not possible; this is only possible for a small range around the best case scenario. For stepping over in three steps this is possible when actuation is applied according to the optimization results presented.

Sometimes children are born with (part of) an arm missing. Next to congenital loss, children or adults can loose their arm due to an accident or illness. The missing arm can be replaced with a prosthesis, connected to the arm remnant by a socket. Existing sockets tend to have a hot and humid climate and some sockets are difficult to don and doff. The WILMER open socket is adjustable but looks bulky. All these disadvantages result in reduced wearing of the prosthesis. After the current prostheses are evaluated, the existing patents and available literature are investigated, a list of requirements was made for a new design. With the requirements, the problem can be solved by improving a current socket and designing new sockets. The application of new materials in prosthetics is evaluated, resulting in several new designs. The WILMER open socket is improved, resulting in another design. From these designs one concept is chosen and detailed. The chosen concept is made of stainless steel wire mesh, with an adjustable condyle brace and a standard forearm shell over the mesh.

Electricity is one of the most utilized energy carriers for energy transmission in the world. In recent years more electricity is generated from renewable energy sources. The main drawback of renewable energy sources is that renewable energy power plants are often connected to certain locations. Sometimes these renewable energy power plants are located in very long distant areas across the sea, so consequently bulk electricity transport to major electric power consuming areas across the sea is not done due to economical difficulties. Therefore the aim of the report is to develop and to analyse different electricity transport concepts to achieve bulk electricity transport across the sea in energy efficient and cost efficient manner. In this case the feasibility of bulk electricity transport between the hydroelectric and geothermal energy sources in Iceland and the electric power consuming areas such as Scotland and European mainland is investigated. During the development of the electricity transport concepts three electricity transport concepts emerged. The three electricity transport concepts are the submarine electric power transmission, the battery ship and the synthetic fuel. In the study the three electricity transport concepts are further developed and analysed. The three electricity transport concepts are analysed by investigating the energetic performance and the cost performance of the three electricity transport concepts for the distances from 0 nautical miles till 6000 nautical miles. In addition the influence of the cost per MWh of power plants on the three electricity transport concepts is examined for the distances of 500 nautical miles and 1000 nautical miles. Currently the electric power transmission with submarine electrical power cables is the only way to deliver electrical energy across the sea. The electric power transmission system is composed of two converter stations and one or two submarine power cables. The other electricity transport concept consists of a battery ship and two small offshore terminals. The battery ship is a 300.000 dwt ship with integrated redox flow batteries. The battery ship is charged and discharged at small offshore terminals. In this report the battery ship is developed till conceptual design. The last electricity transport concept consists mainly of a production plant for the conversion of electricity into synthetic fuel, a cargo ship and a power plant. In the thesis different synthetic fuels are compared. The different synthetic fuels are hydrogen, ammonia, methanol, ethanol, dimethyl ether (DME), sodium borohydride and zinc. The results of the investigation are that the synthetic fuels hydrogen and ammonia are attractive synthetic fuels for bulk electricity sea transport. Hence follows that the bulk electricity sea transport by means of compressed hydrogen and ammonia is examined in more details and afterwards the two synthetic fuels are compared. The comparison shows that ammonia is a more energy efficient and cost efficient synthetic fuel than hydrogen, so ammonia is the appropriate synthetic fuel for the purpose of bulk electricity sea transport. Finally, all electricity transport concepts are compared with each other and evaluated.

In industrial processes about 80% of the energy demand is in the form of heat. One of the problems of the industrial waste heat is the low temperature of this heat. The department of energy efficiency and infrastructure, 'E&I' of the Energy research Center of the Netherlands 'ECN' runs projects in order to use industrial waste heat with a thermoacoustic heat pump. Thermoacoustic engines can deliver the power to drive a thermoacoustic heat pump and can be driven by waste heat. The desired hot temperatures exceed the temperatures of the waste heat. It is believed that more than one thermoacoustic engine is necessary in order to gain sufficient temperature lift. In this study a parallel configuration of thermoacoustic engines is compared to a serial configuration of thermoacoustic engines. Additionally the losses in a coaxial thermoacoustic engine are analyzed. In two sets of experiments two regenerator units were placed in parallel and serial configuration inside a symmetric resonator. The regenerators were heated with an electrical heater and cooled with cooling water. Power was subtracted with a load. The power that can be subtracted by the load is the same as the power that could be used in a heat pump. The main objective is to gain maximum load power with a hot regenerator temperature as low as possible. The experiments show that the serial configuration produced more acoustic power in the load than the parallel configuration. In contrast the efficiency of the power produced in the resonator is found to be about the same for both configurations. This is because of the assumption that the power dissipated in the resonator is equal to twice the power dissipated in an empty half of the resonator, while in reality the power dissipated in the resonator depends also on the internal geometries in the resonator, and the internal velocity. In the present experimental setup the pressure and velocity profile are not the same for serial and parallel configurations. The acoustic power measured in the load is used to compute the external efficiency. The internal efficiency is calculated from the resonator losses and the power measured in the load. The resonator losses were originally determined from two microphone measurements of an empty resonator half, without the consideration of internal geometries. Hence internal efficiencies of the two configurations can not be compared, whereas the external efficiencies can be compared to draw conclusions. In the parallel configuration at a pressure of 19.9 bar, a drive ratio of 3.03 and a heater input of 324 W, 5.96 W of acoustic power can be subtracted while the hot regenerator temperature rises till 274 oC. In the serial configuration at a pressure of 19.5 bar, a drive ratio of 2.95 and a heater input of 367 W, 11.63 W of acoustic power can be subtracted while the hot regenerator temperature rises till 290 oC. This means the 2nd law external efficiency of the serial configuration is 47% better than for the parallel configuration. A calculation predicts that the serial configuration could perform as much as 80% better if the load was placed at the engine side. In cooling, heating, and other processes where the external power is the useful power the serial configuration is the better configuration.

Running robots often have their center of mass (CoM) located on the hip. This decouples the pitching and CoMdynamics and therefore allows for simple control schemes. However, by creating an offset between the CoM and the hip, and herewith introducing coupling between the pitching and CoMdynamics, the performance of the running robot might possibly increase. In this simulation study, we calculated the optimal CoMlocation for a running robot with hip actuation. We measured the performance of the system as the largest step-down and push that can be corrected in one or two steps. We found that the largest step-down can be corrected in one step when the CoM is located above the hip. The largest push on the other hand can be corrected when the CoM is located under the hip. For two-steps recovery strategies, placing the CoM exactly on the hip is the worst option out of all possible CoM-locations. In this case, the corresponding disturbance rejection is approximately a factor 10 worse than for the optimal CoM-location. Therefore, we conclude that placing the CoM of the torso on the hip is far from optimal.

The particular category of the underactuated grippers is chosen for the automation of the item picking in distribution centers. The underactuated grippers have fewer degrees of actuation than degrees of freedom, so they are mechanically simpler than the fully-actuated grippers, and they are able to adapt to objects regardless of their shapes. However, the existing underactuated grippers found in the literature are regarded overdesigned because more than enough passive elements are included. This paper is aimed to design and build a more simplified but still workable underactuated gripper for the item picking. The designed gripper contains a cable-pulley driven underactuated finger which has two phalanges, and an opposite fixed finger. Moreover, the fingertip of the underactuated finger is intended to move along the ground where the target object is laid. The dimensions of the gripper are selected in order to achieve the following two tasks: picking the cylindrical objects from the ground and retaining the grasp during a lifting transportation. The experiment setup fails to drive the fingertip of the underactuated finger moving along the ground, but it is shown that the designed gripper is still able to fulfill these two tasks, except for the case that when the initial spacing between the moving underactuated finger and the object is rather large.