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The purpose of this paper is to describe a compact wheelchair, which has two 3-degrees of freedom (DOF) legs and a 1-DOF base (the total DOF of the leg system is 7) for stair-climbing, and wheels for flat surface driving.

The proposed wheelchair climbs stairs using the two 3-DOF legs with boomerang-shaped feet. The leg mechanisms are folded into the compact wheelchair body when the wheelchair moves over flat surfaces. The authors also propose a simple estimation method of stair shape using laser distance sensors, and a dual motor driving system to increase joint power.

The proposed wheelchair can climb arbitrary height and width stairs by itself, even when they are slightly curved. During climbing, the trajectory of the seat position is linear to guarantee the comfort of rider, and the wheelchair always keeps a stable condition to ensure the stability in an emergency stop.

The wheelchair mechanism with foldable legs and driving wheels enables smooth stair climbing, efficient flat surface driving and additional useful motions such as standing and tilting.

Worksites have been targeted as an important setting for physical activity interventions. A recent emphasis for health promoters is the use of point-of-choice interventions to encourage stair climbing at work. The purpose of this paper is to explore three point-of-choice campaigns to increase stair climbing at work.

Ten focus groups and a rating task were conducted with 59 employees from a University and a University Hospital in the UK. Focus groups were structured around three messages and four prompts and sought to explore the motivational power of the resources, identify factors contributing to their effectiveness and provide recommendations to improve and optimize content. Benefits and barriers to stair climbing at work were also explored. Focus groups were recorded, transcribed and coded to identify key themes.

Intra-personal factors health, motivation, social norms and time management influence stair climbing at work. Critically, extra-personal factors associated with the worksite itself can also bias a traveler’s choice independently of any intervention. Results suggest that messages targeting heart health have the greatest impact on reported propensity to climb the stairs at work. Messages targeting rate of respiration for fitness, however, may have a negative effect given that most people want to avoid getting out of breath at work.

Qualitative research is essential for developing and refining the design detail of point-of-choice interventions and tailoring their components to address individuals’ needs in different settings but there is little evidence of this in practice.

This paper aims to provide a theoretical principle for the stability control of robot climbing stairs, autonomously based on human–robot interaction. Through this research, tracked mobile robots with human-robot interaction will be extensively used in rescue in disaster, exploration on planetary, fighting in battle, and searching for survivors in collapsed buildings.

This paper introduces the tracked mobile robot, based on human–robot interaction, and its six moving postures. The dynamic process of climbing stairs is analyzed, and the dynamic model of the robot is proposed. The dynamic stability criterion is derived when the tracked mobile robot contacts the stairs steps in one, two and more points. A further conduction of simulation on the relationship of the traction force and bearing force vs the velocity and acceleration in the three cases was carried out.

This paper explains that the tracked mobile robot, based on human–robot interaction, can stably climb stairs so long as the velocity and acceleration satisfy the dynamic stability criterion as noted above. In addition, the experiment tests the correctness of dynamic stability analysis when the tracked mobile robot contacts the stair steps in one, two or more points.

This paper provides the mechanical structure and working principle of the tracked mobile robot based on human–robot interaction and proposes an identification method of dynamic stability criterion when the robot contacts the stairs steps in one, two and more points.

Worksites have been targeted as an important setting for physical activity interventions. A recent emphasis for health promoters is the use of point-of-choice interventions to encourage stair climbing at work. The purpose of this paper is to explore campaigns to increase stair climbing at work.

Focus groups were structured around three messages and four prompts and sought to explore the motivational power of the resources, identify factors contributing to their effectiveness and provide recommendations to improve and optimize content. Benefits and barriers to stair climbing at work were also explored.

Health awareness, motivation, social norms and time management influence stair climbing at work. Critically, factors associated with the worksite itself can also bias choice independently of any intervention. Results suggest that messages targeting heart health have the greatest impact on reported propensity to climb the stairs at work. Messages targeting rate of respiration for fitness, however, may have a negative effect, given that most people want to avoid getting out of breath at work.

Qualitative research is essential for developing and refining the design detail of point-of-choice interventions and tailoring their components to address individuals’ needs in different settings, but there is little evidence of this in practice.

The purpose of this paper is to describe an innovative compliance control architecture for hybrid multi‐legged robots. The approach was verified on the hybrid legged‐wheeled robot ASGUARD, which was inspired by quadruped animals. The adaptive compliance controller allows the system to cope with a variety of stairs, very rough terrain, and is also able to move with high velocity on flat ground without changing the control parameters.

The paper shows how this adaptivity results in a versatile controller for hybrid legged‐wheeled robots. For the locomotion control we use an adaptive model of motion pattern generators. The control approach takes into account the proprioceptive information of the torques, which are applied on the legs. The controller itself is embedded on a FPGA‐based, custom designed motor control board. An additional proprioceptive inclination feedback is used to make the same controller more robust in terms of stair‐climbing capabilities.

The robot is well suited for disaster mitigation as well as for urban search and rescue missions, where it is often necessary to place sensors or cameras into dangerous or inaccessible areas to get a better situation awareness for the rescue personnel, before they enter a possibly dangerous area. A rugged, waterproof and dust‐proof corpus and the ability to swim are additional features of the robot.

Contrary to existing approaches, a pre‐defined walking pattern for stair‐climbing was not used, but an adaptive approach based only on internal sensor information. In contrast to many other walking pattern based robots, the direct proprioceptive feedback was used in order to modify the internal control loop, thus adapting the compliance of each leg on‐line.

The purpose of this paper is to present the mechanical design and stability analysis of a new stair‐climbing robotic wheelchair.

A prototype stair‐climbing robotic wheelchair is constructed comprising a pair of rotational multi‐limbed structures pivotally mounted on opposite sides of a support base. The short arm, long arm, and triangular support structures within each rotational multi‐limbed structure rotate under the actuating effects of epicyclical gear trains.

The robotic wheelchair ascends and descends stairs in a statically stable manner and has an efficient planar navigation capability.

In its current state of development, the robotic wheelchair is controlled and powered remotely via umbilical cords rather than an onboard processor and power supply.

The robotic wheelchair provides an effective solution for enhancing the mobility of the elderly and disabled.

The rotational multi‐limbed mechanisms are developed to ensure the stability of the sitting base at all stages of the stair navigation maneuver without the need for additional servo‐mechanism. The proposed robotic wheelchair shows the simplification of the associated operation process.

The purpose of this research is to evaluate the impact of theory‐based poster messages on stair‐climbing behaviour in a work environment. The highest‐rated poster developed by the Public Health Agency of Canada's stairway to health program was used as a comparison condition.

Naturalistic observation of stair traffic was conducted in order to measure the effectiveness of poster prompts on stair‐climbing behaviour. Over a period of three years, three separate studies were conducted aimed at increasing stair‐use via experimentally manipulated and theory‐based poster messages.

Results suggest that messages derived from a norm‐based framework are more persuasive than generic information‐based posters when attempting to increase stair‐climbing behaviour.

Small increases in health‐related behaviours at work have important consequences for both individuals and organizations. Using poster messages derived from social psychological theory could prove advantageous for practitioners attempting to increase healthy behaviours at work.

This research provides the first evidence for the use of norm‐based health‐related messages targeted at increasing healthy behaviours. The study makes a theoretical contribution to the creation and application of norm‐based appeals using both simple and complex message framing. Prior to this study, there was no available research on the effectiveness of such appeals on health‐related behaviour.

Increasing physical activity (PA) is an international public health priority. This study aims to assess the impact of an environmental stair‐use intervention using “point of decision” prompts with varying messages in an NHS workplace in the UK.

Observational data were collected using a covert method (infra‐red sensors) in an interrupted time‐series design over an eight‐week period. Intervention consisted of posters displaying encouraging messages in the entrance to two stairways of an acute NHS hospital. The hospital site is a public building accessible to patients, staff (n=∼7,000), students and the general public. Questionnaires (n=221) assessed employee self‐reports of and attitudes towards stair‐use.

Following 24‐hour observational counts (n=143,514) no statistically significant differences were seen in either stair climbing or descent on either stairway through the introduction and removal of promotional posters. A number of determinants and barriers to stair‐use were identified. Posters were reported as “seen” by a low proportion of respondents (7‐25 per cent) and only a small number felt encouraged to use the stairs as a result of the prompts (25‐37 per cent of those who “saw” them, 3‐18 per cent of total sample).

The study evaluates the impact of a stair‐use intervention in a public hospital building, a setting within which research investigations have to date been limited. More research is needed to further investigate determinants and barriers to stair‐use and the impact of different message types and locations of “point‐of‐decision” prompts in a hospital setting.

Environmental interventions to increase stair‐use in this setting may be best placed within a comprehensive workplace programme including health education and multi‐component interventions.

“Point of decision” prompts are inexpensive as a long‐term intervention. As part of a large‐scale workplace health campaign, encouraging even a small percentage of employees to use the stairs in organisations of this size is of significance to workplace health promoters.

This paper aims to investigate weight-climbing assistance strategy for the biomechanical design of passive knee-assisting exoskeleton (PKAExo) and evaluate a designed PKAExo which stores energy when the knee joint flexes and releases the energy to assist ascending when the knee joint extends.

The authors constructed theoretic modeling of human weight-climbing to analyze characteristics of knee angle and moment. They then conducted camera-based movement analysis, muscle strength and endurance tests and surface electromyography (sEMG) measures to verify the relationship of knee angle and moment with both stair height and load weight. Afterwards, the authors proposed an assistant strategy for passive knee assistance, then gave out designed PKAExo and conducted mechanical experiment to test the knee-assisting torque. Finally, the authors conducted comparison experiment based on measuring the sEMG signals of knee extensor to verify the assistance effect of the PKAExo for weight-climbing.

The knee extensor produces the maximum force during weight-climbing, and the muscle force provided by knee extensor has significant increasing rate along with the stair height. Thus, the assistance torque of PKAExo is designed to increase nonlinearly along with increasing knee angle. It stores energy when knee flexes and assists when knee extends. Both the mechanical experiment and comparison experiment have demonstrated that the PKAExo is able to provide nonlinear assistance torque for weight-climbing, thus decreasing the average maximum load of knee extensor by about 21 per cent, reducing muscle fatigue and enhancing wearer’s weight-climbing ability.

The authors construct theoretic maximum force model produced by knee extensor for weight-climbing in static situation and conduct a series of experiments to verify and revise the model, which is the fundamental reference for knee-assisting mechanism designed for weight-climbing. The authors have also provided and validated an assistant strategy and the mechanism based on the biomechanical analysis, which aims to translate wearer’s energy-providing mode form high load to mid-low load by storing energy when knee flexes and assisting when knee extends. The PKAExo decreases the maximum load of knee extensor, reduces muscle fatigue and helps people to easily climb with load.

The purpose of this paper is to study the adaptability of the tracked robot in complex working environment. It proposes an angle-changeable tracked robot with human–robot interaction in unstructured environment. The study aims to present the mechanical structure and human–robot interaction control system of the tracked robot and analyze the static stability of the robot working in three terrains, i.e. rugged terrain, sloped terrain and stairs.

The paper presents the mechanical structure and human–robot interaction control system of the tracked robot. To prevent the detachment of the tracks during obstacle navigation, a new type of passively adaptive device based on the relationship between the track’s variable angle and the forces is presented. Then three types of rough terrain are chosen to analyze the static stability of the tracked robot, i.e. rugged terrain, sloped terrain and stairs.

This paper provides the design method of the tracked robot. Owing to its appropriate dimensions, good mass distribution and limited velocity, the tracked robot remains stable on the complex terrains. The experimental results verify the effectiveness of the design method.

The theoretical analysis of this paper provides basic reference for the structural design of tracked robots.