The existing shortage of therapists and caregivers assisting physically disabled individuals at home is expected to increase and become serious problem in the near future The patient population needing physical rehabilitation of the upper extremity is also constantly increasing Robotic devices have the potential to address this problem as noted by the results of recent research studies However, the availability of these devices in clinical settings is limited, leaving plenty of room for improvement The purpose of this paper is to document a review of robotic devices for upper limb rehabilitation including those in developing phase in order to provide a comprehensive reference about existing solutions and facilitate the development of new and improved devices In particular the following issues are discussed: application field, target group, type of assistance, mechanical design, control strategy and clinical evaluation This paper also includes a comprehensive, tabulated comparison of technical solutions implemented in various systems

/pdf/a-survey-on-robotic-devices-for-upper-limb-rehabilitation-3ykq953s17.pdf

A survey on robotic devices for upper limb rehabilitation

The existing shortage of therapists and caregivers assisting physically disabled individuals at home is expected to increase and become serious problem in the near future. The patient population needing physical rehabilitation of the upper extremity is also constantly increasing. Robotic devices have the potential to address this problem as noted by the results of recent research studies. However, the availability of these devices in clinical settings is limited, leaving plenty of room for improvement. The purpose of this paper is to document a review of robotic devices for upper limb rehabilitation including those in developing phase in order to provide a comprehensive reference about existing solutions and facilitate the development of new and improved devices. In particular the following issues are discussed: application field, target group, type of assistance, mechanical design, control strategy and clinical evaluation. This paper also includes a comprehensive, tabulated comparison of technical solutions implemented in various systems.

A survey on robotic devices for upper limb

http://sensorimotorcontrolatorium.uic.edu/uploads/3/8/9/6/38963381/aubernikerherr.pdf

2008 Special Issue: Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits

At moderate to fast walking speeds, the human ankle provides net positive work at high-mechanical-power output to propel the body upward and forward during the stance period. On the contrary, conventional ankle-foot prostheses exhibit a passive-elastic response during stance, and consequently, cannot provide net work. Clinical studies indicate that transtibial amputees using conventional prostheses have higher gait metabolic rates than normal. Researchers believe that the main cause for these higher rates is due to the inability of conventional prostheses to provide sufficient positive power at terminal stance in the trailing leg to limit heel strike losses of the adjacent leading leg. In this investigation, we evaluate the hypothesis that a powered ankle-foot prosthesis, capable of providing human-like ankle work and power during stance, can decrease the metabolic cost of transport (COT) compared to a conventional passive-elastic prosthesis. To test the hypothesis, a powered prosthesis is built that comprises a unidirectional spring, configured in parallel with a force-controllable actuator with series elasticity. The prosthesis is shown to deliver the high mechanical power and net positive work observed in normal human walking. The rate of oxygen consumption and carbon dioxide production is measured as a determinant of metabolic rate on three unilateral transtibial amputees walking at self-selected speeds. We find that the powered prosthesis decreases the amputee's metabolic COT on average by 14% compared to the conventional passive-elastic prostheses evaluated (Flex-Foot Ceterusreg and Freedom Innovations Sierra), even though the powered system is over twofold heavier than the conventional devices. These results highlight the clinical importance of prosthetic interventions that closely mimic the mass distribution, kinetics, and kinematics of the missing limb.

/pdf/powered-ankle-foot-prosthesis-improves-walking-metabolic-1tkwrar248.pdf

Powered Ankle--Foot Prosthesis Improves Walking Metabolic Economy

Over time, leg prostheses have improved in design, but have been incapable of actively adapting to different walking velocities in a manner comparable to a biological limb. People with a leg amputation using such commercially available passive-elastic prostheses require significantly more metabolic energy to walk at the same velocities, prefer to walk slower and have abnormal biomechanics compared with non-amputees. A bionic prosthesis has been developed that emulates the function of a biological ankle during level-ground walking, specifically providing the net positive work required for a range of walking velocities. We compared metabolic energy costs, preferred velocities and biomechanical patterns of seven people with a unilateral transtibial amputation using the bionic prosthesis and using their own passive-elastic prosthesis to those of seven non-amputees during level-ground walking. Compared with using a passive-elastic prosthesis, using the bionic prosthesis decreased metabolic cost by 8 per cent, increased trailing prosthetic leg mechanical work by 57 per cent and decreased the leading biological leg mechanical work by 10 per cent, on average, across walking velocities of 0.75–1.75 m s−1 and increased preferred walking velocity by 23 per cent. Using the bionic prosthesis resulted in metabolic energy costs, preferred walking velocities and biomechanical patterns that were not significantly different from people without an amputation.

https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2011.1194

Bionic ankle–foot prosthesis normalizes walking gait for persons with leg amputation

Numerous prosthetic feet are currently on the market for individuals with a transtibial amputation, each device aimed at raising the 3C-level (control, comfort and cosmetics) with slightly different characteristics. In general, prosthetic feet can be classified into three categories. These are, following the time line: conventional feet (CF), energy-storing-and-returning (ESR) feet and the recent so-called ‘bionic’ feet. Researchers have shown enhanced performance properties of ESR feet compared with early CF. However, even with the advanced technology, none of the ESR feet is capable of significantly reducing energy cost of walking or enhancing prosthetic gait (Nielsen et al. J Prosthet Orthotics 1989;1:24–31; Waters et al. J Bone Joint Surg Am 1976;58:42–46; Torburn et al. J Rehabil Res Dev 1990;27:369–384). From the 1990s, gradually more attention has been paid to the incorporation of active elements in prosthetic feet as the passive devices are not capable of providing the individual with sufficient a...

Prosthetic feet: State-of-the-art review and the importance of mimicking human ankle–foot biomechanics

Due to its high power-to-weight ratio, a pleated pneumatic artificial muscle (PPAM) offers an interesting alternative actuation source for robotic devices. Its inherent compliant behaviour excites another broad field of interest: assistive clinical devices such as powered exoskeletons and prosthetics. In this paper, the design of a pneumatically powered transtibial prosthetic device is presented. A first prototype has been built and provides a preliminary test bed for control algorithm development and testing with able-bodied subjects in laboratory conditions. The characteristics and working principle of a PPAM are described. The design specifications and the mechanical model of the prosthesis are discussed. The mechanical design and the control structure are outlined. Furthermore, some initial walking trials with an able-bodied subject wearing the prosthesis prototype are presented and discussed.

A biomechatronical transtibial prosthesis powered by pleated pneumatic artificial muscles

In situations where robots share their workspace with humans, and where physical human-robot interaction is possible or even necessary, safety is of paramount importance. This paper presents a study of the safety of a lightweight robot actuated by pneumatic muscles. Due to its low weight, it has excellent hardware safety characteristics. In spite of this, it is shown that the system can be unsafe when under PID control. It is also shown that safety can be greatly increased by using Proxy-Based Sliding Mode Control (PSMC). The role of passive compliance in safety is also investigated. It is argued that passive compliance can have positive as well as negative effects on robot safety, depending on the situation.

The Safety of a Robot Actuated by Pneumatic Muscles—A Case Study

This paper presents the results of preliminary walking experiments on a transtibial amputee wearing a powered prosthesis. The prosthesis prototype serves as a proof-of-concept implementation for investigating the potential of pleated pneumatic artificial muscles to power a transtibial prosthesis. The device is equipped with pleated pneumatic artificial muscles, and tethered to a laboratory pressure source. The prosthesis is capable of providing the amputee with 100% of the required push-off torque and it can adapt its joint stiffness to the walking speed. This study supports the hypothesis that a powered transtibial prosthesis with adaptable stiffness might be beneficial to the amputee.

https://poi.sagepub.com/content/33/4/368.full.pdf

Successful preliminary walking experiments on a transtibial amputee fitted with a powered prosthesis.

This paper reports on the powered elbow orthosis for orthopaedic rehabilitation project and its main challenges. The mechanical design is briefly discussed. The actuator being used is the novel rotational actuator, MACCEPA or Mechanically Adjustable Compliance and Controllable Equilibrium Position Actuator. The schematic representation and working principle of this actuator are recapitulated in short before describing the mathematical model of the orthosis and the choices made to find a balance between simplicity, usefulness and correspondence with reality.

Rino Versluys

Papers

Prosthetic feet: State-of-the-art review and the importance of mimicking human ankle–foot biomechanics

A biomechatronical transtibial prosthesis powered by pleated pneumatic artificial muscles

The Safety of a Robot Actuated by Pneumatic Muscles—A Case Study

Successful preliminary walking experiments on a transtibial amputee fitted with a powered prosthesis.

Orthopaedic rehabilitation: A powered elbow orthosis using compliant actuation