Manipulating objects with a power assist robot in harmonic motion: Analysis of human features and object motions for control modification

We designed a one-degree-of-freedom (vertical up-down motion) power assist robot for manipulating objects. We used a hypothesis that pertains to human's weight perception. The robot was simulated and subjects manipulated objects with the robot in harmonic motion i.e. the objects were repeatedly lifted up and lowered down in each trial. We then critically analyzed subject's weight perception, load forces and object's motions. We also compared the results derived in harmonic motion to that derived in linear vertical motion. We then proposed a novel control technique to reduce the excessive load forces applied by the subjects. We explained how the findings derived in this article would enhance the effectiveness of the novel control strategy. Finally, we proposed to use the findings to develop power assist robots to manipulate heavy objects in industries such as construction, transport and logistics, manufacturing and assembly, mining, rescue and military operations etc. that would enhance interactions with the users in terms of maneuverability, safety, naturalness, ease of use, stability etc.