Dick Plettenburg

• Delft University of Technology

Individuals with lower limb amputation experience reduced ankle push-off work in the absence of functional muscles spanning the joint, leading to decreased walking performance. Conventional energy storage and return (ESR) prostheses partially compensate by storing mechanical energy during midstance and returning this energy during the terminal stan...

Various upper-limb prostheses have been designed for 3D printing but only a few of them are based on bio-inspired design principles and many anatomical details are not typically incorporated even though 3D printing offers advantages that facilitate the application of such design principles. We therefore aimed to apply a bio-inspired approach to the...

With recent improvements in healthcare, individuals with Duchenne muscular dystrophy (DMD) have prolonged life expectancy, and it is therefore vital to preserve their independence. Hand function plays a central role in maintaining independence in daily living. This requires sufficient grip force and the ability to modulate it with no substantially...

Operating a body-powered prosthesis can be painful and tiring due to high cable operation forces, illustrating that low cable operation forces are a desirable design property for body-powered prostheses. However, lower operation forces might negatively affect controllability and force perception, which is plausible but not known. This study aims to...

In developing countries, the access of amputees to prosthetic devices is very limited. In a way to increase accessibility of prosthetic hands, we have recently developed a new approach for the design and 3D printing of non-assembly active hand prostheses using inexpensive 3D printers working on the basis of material extrusion technology. This artic...

While designing a dynamic hand orthosis to assist during activities of daily living, the designer has to know whether a concept will have sufficient grasp performance to support these activities. This is often estimated by measuring the interaction force at the contact interface. However, this requires a prototyping step and limits the practicality...

Upper extremity function is affected by a variety of neurological conditions. Robotic exoskeletons offer a potential solution for motor restoration. However, their systematic adoption is limited by challenges relative to human intention detection and device control. This position paper offers a focused perspective on this topic. That is, on how kno...

To design an underactuated wrist prosthesis, a preliminary study has been conducted to identify the relationship between the Degrees of Freedom (DoFs) of the wrist during the execution of tasks of daily living. After the identification of the principal orientations of the wrist describing the tasks, polynomial functions were used to define a synerg...

For the first time, a person with Duchenne muscular dystrophy is controlling an active hand orthosis. In this case study, we decoded the hand motor intention of the participant, using direct sEMG, for the control of an underactuated hand orthosis we developed (SymbiHand). Link: https://www.youtube.com/watch?v=jpHjlFM0t3Y&feature=youtu.be

People with Duchenne muscular dystrophy are currently in need of assistive robotics to improve their hand function and have a better quality of life. However, none of the available active hand orthoses is able to address to their specific needs. In this study, the use of hydraulic technology is proposed in the design of an active hand orthosis. Com...

Fabrication of complex and multi-articulated mechanisms is often seen as a time consuming and demanding process. The development of functional multi-articulated mechanisms that could be fabricated in a single step without the need for post-manufacturing assembly is therefore very attractive. Additive manufacturing (AM) has been pointed out as a fea...

The addition of a cosmetic glove to an upper limb prosthesis has a distinct effect on the cosmetic value, but its viscoelastic behaviour adds a substantial amount of stiffness and hysteresis to the system. As a result, the overall usability of the prosthesis is degraded. A novel negative stiffness element is designed to compensate for the cosmetic...

Raw measurement data. (ZIP)

This study does not describe a success-story. Instead, it describes an exploratory process and the lessons learned while designing a compliant mechanism for a dynamic hand orthosis. Tools from engineering optimization and rapid prototyping techniques were used, with the goal to design a mechanism to compensate for hypertonic or contracted finger mu...

State of art upper limb prostheses lack several degrees of freedom (DoF) and force the individuals to compensate for them by changing the motions of their arms and body. Such movements often yield to articulation injuries, nonetheless these could be prevented by adding DoFs, for instance, an articulated passive wrist. Available stiff or compliant w...

Background: Body-powered prostheses require cable operation forces between 33 and 131 N. The accepted upper limit for fatigue-free long-duration operation is 20% of a users' maximum cable operation force. However, no information is available on users' maximum force. Objectives: To quantify users' maximum cable operation force and to relate this...

Background: Body-powered prosthesis users frequently complain about the poor cosmesis and comfort of the traditional shoulder harness. The Ipsilateral Scapular Cutaneous Anchor System offers an alternative, but it remains unclear to what extent it affects the perception and control of cable operation forces compared to the traditional shoulder har...

Background: The group of passive prostheses consists of prosthetic hands and prosthetic tools. These can either be static or adjustable. Limited research and development on passive prostheses has been performed although many people use these prosthesis types. Although some publications describe passive prostheses, no recent review of the peer-revi...

Background It is generally asserted that reliable and intuitive control of upper-limb prostheses requires adequate feedback of prosthetic finger positions and pinch forces applied to objects. Body-powered prostheses (BPPs) provide the user with direct proprioceptive feedback. Currently available BPPs often require high cable operation forces, which...

Background Little is known about action-perception learning processes underlying prosthetic skills in body-powered prosthesis users. Body-powered prostheses are controlled through a harness connected by a cable that might provide for limited proprioceptive feedback. This study aims to test transfer of training basic tasks to functional tasks and to...

The development of dynamic hand orthoses is a fast-growing field of research and has resulted in many different devices. A large and diverse solution space is formed by the various mechatronic components which are used in these devices. They are the result of making complex design choices within the constraints imposed by the application, the envir...

Objective: This review aims to provide a structured classification of the underlying steering mechanisms in steerable catheters and to assess their future challenges. Methods: Existing, patented, and experimental designs of steerable catheters are classified with respect to their steerability. Subsequently, the classification is used as a tool f...

Background: The functional performance of currently available body-powered prostheses is unknown. Objective: The goal of this study was to objectively assess and compare the functional performance of three commonly used body-powered upper limb terminal devices. Study design: Experimental trial. Methods: A total of 21 able-bodied subjects (n...

Rejection rates of upper limb prostheses are high (23-45%). Amputees indicate that the highest design priority should be reduction of the mass of the prosthetic device. Despite all efforts, the mass of the new prosthetic hands is 35-73% higher than that of older hands. Furthermore current hands are thicker than a human hand, they operate slower and...

The goal of this study was to find an efficient method of energy transmission for application in an anthropomorphic underactuated body-powered (BP) prosthetic hand. A pulley-cable finger and a hydraulic cylinder finger were designed and tested to compare the pulley-cable transmission principle with the hydraulic cylinder transmission principle. Bot...

Current articulating electric and body-powered hands have a lower pinch force (15-34 N) than electric hands with stiff fingers (55-100 N). The cosmetic glove, which covers a hand prosthesis, negatively affects the mechanical efficiency of a prosthesis. The goal of this study is to mechanically compare polyvinylchloride (PVC) and silicone cosmetic g...

Background: Cosmetic gloves that cover a prosthetic hand have a parasitic positive stiffness that counteracts the flexion of a finger joint. Objectives: Reducing the required input torque to move a finger of a prosthetic hand by compensating the parasitic stiffness of the cosmetic glove. Study design: Experimental, test bench. Methods: The p...

Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the best tested device. A second goal was to see whethe...

DC motors are currently the preferred actuation method for externally powered hand prostheses. However, they are often heavy and large, which limits the number of actuators that can be integrated into the prosthesis. Alternative actuation methods are being researched, but have not yet found wide application. In this paper, a thin-walled pneumatic c...

This article addresses the neuromotor control processes underlying the use of an upper limb prosthesis. Knowledge of these processes is used to make recommendations as to how prostheses and prosthesis training should develop to advance the functionality of upper limb prostheses. Obviously, modern-day prostheses are not optimally integrated in neuro...

Body powered hand prostheses require a high physical user effort. This is caused by the stiffness of the cosmetic covering, or cosmetic glove. This paper aims to present a new concept of a mechanisms for the compensation of the nonlinear stiffness of hand prostheses by using statically balanced mechanisms with a nonlinear behavior. This concept is...

Recent developments in flexible endoscopy and other fields of medical technology have raised the need for compact slender shafts that can be made rigid and compliant at will. A novel compact mechanism, named FORGUIDE, with this functionality was developed. The FORGUIDE shaft rigidifies due to friction between a ring of cables situated between a spr...

Recent developments in flexible endoscopy and other fields of medical technology have raised the need for compact slender shafts that can be made rigid and compliant at will. A novel compact mechanism, named FORGUIDE, with this functionality was developed. The FORGUIDE shaft rigidifies due to friction between a ring of cables situated between a spr...

Rejection rates of body-powered hands are higher than that of hooks. Body powered hands are inefficient. As a result they require an uncomfortable high activation force, and produce a relatively low pinch force in return (<15 N). Also they have stiff fingers, which do not adapt to the shape of the grasped object. Despite all the drawbacks of the cu...

The Delft Institute of Prosthetics and Orthotics has started a research program to develop an improved voluntary closing, body-powered hand prosthesis. Five commercially available voluntary closing terminal devices were mechanically tested: three hands [Hosmer APRL VC hand, Hosmer Soft VC Male hand, Otto Bock 8K24] and two hooks [Hosmer APRL VC hoo...

Although hand prostheses with a cosmetic covering are commercially available for disabled people, the operating effort due to the stiffness of the mechanism is high. This results in high power requirements. This paper aims to present a new concept of mechanisms for the compensation of the nonlinear stiffness of hand prostheses by using statically b...

Snowboarding with a below-knee prosthesis is compromised by the limited rotation capabilities of the existing below-knee prostheses, which are designed for use in normal walking. Based on snowboarding range of motion analyses, a novel below-knee prosthesis was designed with the aim to achieve similar range of motions like able-bodied snowboarders....

Snowboarding with a below-knee prosthesis is compromised by the limited rotation capabilities of the existing below-knee prostheses, which are designed for use in normal walking. Based on snowboarding range of motion analyses, a novel below-knee prosthesis was designed with the aim to achieve similar range of motions like able-bodied snowboarders....

The WILMER Passive Hand Prosthesis is developed for children aged one through five years. This harnessless hand prosthesis aims primarily at giving the child two arms of equal length. The hand features an easy to control passive prehension function. The movements of the fingers are mechanically coupled to the movements of the thumb. By pressing an...

For people without the ability to use their hands, gripper-equipped robotic aids may provide partial rehabilitation. This article discusses the optimization of an underactuated mechanism for a new prototype gripper on robotic aid ARM. When the underactuated mechanism of the tentacle-like Soft Gripper is translated to a three-phalange equivalent for...

The WILMER elbow orthosis enables patients with a paralysed elbow to actively move their flail arm again. A purely mechanical spring mechanism compensates the gravity forces acting on the forearm of the patient. An automatic locking mechanism enables the patient to retain the flail arm in two positions: one at a nearly extended elbow position and a...

In literature a high power to weight ratio is mentioned among the assumed advantages of pneumatic artificial muscles over other types of actuators. In this paper a comparison was made between pneumatic artificial muscle type actuators and cylinder actuators on the basis of energy to mass ratio. When compared to standard industrial cylinder actuator...

A new type prosthetic prehensor for children aged 4 – 9 has been designed, constructed and build in an attempt to improve the appearance of the split-hook prosthesis. The new prehensor is a mechanically operated voluntary opening device. All mechanical parts are within the frame, and covered by a polyurethane cosmetic cover, which can be made in al...

Many prostheses are not being used because of the discrepancy between the expectations of patients with an arm defect and the reality. A patient wants and expects a prosthesis that looks naturally beautiful, that is comfortable to wear and that is easy to use. None of the existing prostheses fulfills all these demands. Based on patient preference a...

For cosmetic reasons, hand prostheses are provided with cosmetic gloves. Their pleasing appearance, however, is accompanied by poor mechanical behavior, resulting in a negative influence on prosthesis operation. Glove stiffness is high and nonlinear, and internal friction in the glove material causes energy dissipation (hysteresis). In this article...

Many prostheses are not being used because of the discrepancy between the expectations of patients with an arm defect and the reality. A patient wants and expects a prosthesis that looks naturally beautiful, that is comfortable to wear and that is easy to use. None of the existing prostheses fulfils all these demands. Nevertheless by soundly inform...

Most externally powered hand prostheses for children with a unilateral congenital below-elbow amputation are myoelectrically controlled. All of them are electrically powered. Despite the success of fitting children with this kind of prostheses, there are some disadvantages: prosthetic weight is high, operating speed is low, the system is vulnerable...

Electrically actuated hand prostheses have the disadvantage of a high prosthetic mass, a slow cycle time, vulnerability, and an excessive volume. Pneumatical actuation can overcome these disadvantages. To demonstrate the feasibility of pneumatic actuation a pneumatically powered hand prosthesis has been developed. A careful assessment of the system...

To achieve subconscious prosthetic control the patient feedback present must be employed as completely as possible. This implies the use of control methods based upon the principles of extended physiological proprioception. The harnessing of body movements has the inherent ability to fully employ the principles of extended physiological propriocept...