Comfort During Prolonged Exposure to Repetitive Forces Mimicking Exoskeleton Use
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 15
- 试验地点
- 1
- 主要终点
- Perceived discomfort as indicated on a 10 mm visual analog scale (VAS) by the participants, ranking from 'no discomfort' to 'worst imaginable comfort' (10)
研究概览
简要总结
Exoskeletons can be used for rehabilitation, as assistive device for patients, or to support workers during strenuous tasks. To fulfil their purpose, they need to apply forces to the user's musculoskeletal system. The forces are transmitted at skin level through an interface, often in the form of cuffs. Adverse events causing discomfort and injuries to the skin and underlying tissue can be attributed to those interaction forces. While there is some information about safe limit values for impact forces or pressure and shear applied for short durations, little is known regarding comfort and safety thresholds for repetitive forces applied over long durations as is the case in exoskeleton use. This study therefore aims at gaining new knowledge on safe and limit values, based on discomfort (staying below pain threshold), for continuous repetitive shear and normal forces applied through a cuff.
Therefore, the primary objective is to determine comfort thresholds for prolonged exposure to repetitive normal and shear stress exerted to the human thigh via a cuff with straps, using different force patterns comparable to those exerted during exoskeleton use. The secondary objectives are to determine the feasibility of the experiment, the influence of subject characteristics on comfort thresholds, the occurrence of skin injuries or other negative signs, and whether characteristics of muscle activity can be related to discomfort.
详细描述
Rationale: Exoskeletons can be used for rehabilitation, as assistive device for patients, or to support workers during strenuous tasks. To fulfil their purpose, they need to apply forces to the user's musculoskeletal system. The forces are transmitted at skin level through an interface, often in the form of cuffs. Adverse events causing discomfort and injuries to the skin and underlying tissue can be attributed to those interaction forces. While there is some information about safe limit values for impact forces or pressure and shear applied for short durations, little is known regarding comfort and safety thresholds for repetitive forces applied over long durations as is the case in exoskeleton use. This study therefore aims at gaining new knowledge on safe and limit values, based on discomfort (staying below pain threshold), for continuous repetitive shear and normal forces applied through a cuff.
Objective: The primary objective is to determine comfort thresholds for prolonged exposure to repetitive normal and shear stress exerted to the human thigh via a cuff with straps, using different force patterns comparable to those exerted during exoskeleton use. The secondary objectives are to determine the feasibility of the experiment, the influence of subject characteristics on comfort thresholds, the occurrence of skin injuries or other negative signs, and whether characteristics of muscle activity can be related to discomfort.
Study design: The study is a cross-sectional intervention study with one measurement session, where participants will provide a continuous comfort rating during exposure to repetitive normal and shear forces.
Study population: The aim is to include 20 healthy participants in total, matching the age groups 18-35 and 55-85.
Intervention: A pre-defined set of prolonged repetitive force patterns will be applied to each participant's thigh though a contact force which is similar to cuffs commonly used in gait exoskeletons. The forces will be applied by a custom made actuated test device and are based on normal use of exoskeletons.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Between 18 and 35 or between 55 and 85 years of age
- •Able to provide informed consent
排除标准
- •Unable to follow simple instructions
- •Insufficient knowledge of the Dutch or English language to understand the purpose and methods of the study
- •skin lesions at the thigh
- •sensory impairments
- •severe blood pressure fluctuations
- •inability to sit in required posture in experiment chair for 60 minutes
- •taking blood thinners or showing signs for increased bleeding tendency
结局指标
主要结局
Perceived discomfort as indicated on a 10 mm visual analog scale (VAS) by the participants, ranking from 'no discomfort' to 'worst imaginable comfort' (10)
时间窗: 80 minutes
The level of discomfort will be indicated on a VAS as a percentage of maximum imaginable discomfort through a slider that is positioned within reach of the subjects. It will be synchronized with the forces exerted in relation to time. The onset of discomfort, i.e. the point at which the slider of the VAS is first moved to a position \>0, is recorded as discomfort detection threshold (DDT). If the participant activates the enabling switch indicating that the force creates pain rather than discomfort, this point is recorded as pain detection threshold (PDT).
次要结局
- Number of completed test sessions/dropouts(160 minutes)
- Occurrence of injuries or other negative signs(30 minutes)
- Surface Electromyography (EMG) recordings of Rectus femoris(120 minutes)