Autonomous Locomotion Mode Transition Simulation of a Track-legged Quadruped Robot Step Negotiation

Multi-modal locomotion (e.g. terrestrial, aerial, and aquatic) is gaining increasing interest in robotics research as it improves the robots environmental adaptability, locomotion versatility, and operational flexibility. Within the terrestrial multiple locomotion robots, the advantage of hybrid robots stems from their multiple (two or more) locomotion modes, among which robots can select from depending on the encountering terrain conditions. However, there are many challenges in improving the autonomy of the locomotion mode transition between their multiple locomotion modes. This work proposed a method to realize an autonomous locomotion mode transition of a track-legged quadruped robot steps negotiation. The autonomy of the decision-making process was realized by the proposed criterion to comparing energy performances of the rolling and walking locomotion modes. Two climbing gaits were proposed to achieve smooth steps negotiation behaviours for energy evaluation purposes. Simulations showed autonomous locomotion mode transitions were realized for negotiations of steps with different height. The proposed method is generic enough to be utilized to other hybrid robots after some pre-studies of their locomotion energy performances

Associations between hoof lesions and locomotion score in 1098 unsound dairy cows

To investigate the association between locomotion score and types of hoof lesion, cows from 91 selected dairy herds in southern Chile were studied. The locomotion score was recorded for all of the lactating cows (n = 10,699). The mean prevalence of lame cows, when all locomotion scores >1 were included was 33.2% in large herds and 28.7% in small herds. There were 39.7%, 42%, 17.9% and 0.4% cows with locomotion scores of 2, 3, 4 and 5, respectively. Feet (with locomotion scores representative of all severities of lameness) were examined on 676 cows from 34 large herds and 422 cows from 57 small herds. The prevalence of lesions by type ranged from 65% of cattle with at least one white line lesion to 2% of cattle with an interdigital growth. The lesions linked with increasingly poor locomotion were sole ulcer, double sole and interdigital purulent inflammation. There was correlation between claw skin lesions and also between sole ulcer and double sole within cows. It was concluded that the presence of a lesion does not imply that it is necessarily associated with increasing locomotion score. The lack of association between certain lesions and poor locomotion scores indicates either that these lesions are causing different severities of lameness, or that the case definitions used were not sufficiently precise. Locomotion score may not be sensitive enough to detect all lesions (and possibly discomfort)

The Problem of Adhesion Methods and Locomotion Mechanism Development for Wall-Climbing Robots

This review considers a problem in the development of mobile robot adhesion methods with vertical surfaces and the appropriate locomotion mechanism design. The evolution of adhesion methods for wall-climbing robots (based on friction, magnetic forces, air pressure, electrostatic adhesion, molecular forces, rheological properties of fluids and their combinations) and their locomotion principles (wheeled, tracked, walking, sliding framed and hybrid) is studied. Wall-climbing robots are classified according to the applications, adhesion methods and locomotion mechanisms. The advantages and disadvantages of various adhesion methods and locomotion mechanisms are analyzed in terms of mobility, noiselessness, autonomy and energy efficiency. Focus is placed on the physical and technical aspects of the adhesion methods and the possibility of combining adhesion and locomotion methods

The inter- and intra-observer reliability of a locomotion scoring scale for sheep

A seven point locomotion scoring scale, ranging from 0 = normal locomotion to 6 = unable to stand or move, has been developed. To test the between and within observer reliability of the scale, 65 movie clips of sheep with normal and varying degrees of abnormal locomotion were made. Three observers familiar with sheep locomotion were trained to read the movie clips. Thirty clips were randomly selected and used to test between and within observer agreement. There was high inter-(intra-class correlation coefficient [ICC] = 0.93, weighted kappa [κw] = 0.93) and intra-(ICC = 0.90, κw = 0.91) observer reliability, with no evidence of observer bias. The main between score differences were for scores 0 (normal) and 1 (uneven posture and shortened stride but no head movement). The results indicate that the locomotion scoring scale using groups of defined observations for each point on the scale was reliable and may be a useful research tool to identify and monitor locomotion in individual sheep when used by trained observers