Background: Current research, surrounding motor laterality at a population level in horses, indicates that in order to stand with the left forelimb in advance of the other, it is achieved by taking a greater amount of steps with the left foreleg than the right foreleg (McGreevy & Thomson 2006; McGreevy et al. 2007); suggesting that pedometers could effectively estimate asymmetry of forelimb locomotion in grazing horses. This novel method of detecting forelimb preference also reduces the likelihood of operator influence and provides an inexpensive objective measure of vertical movement which has the advantage of scoring large sample sizes, avoids single-day anomalies by recording over multiple days and overcomes logistical challenges (Vincent & Sidman 2003; Chan et al. 2005; Silva et al. 2010; Warren-Smith & McGreevy 2010). However in order to determine the reliability and validity of this novel measure the relationship between pedometer data and those derived from direct observation will first need to be assessed (Warren-Smith and McGreevy 2010). Objectives: To determine: (1) if pedometers accurately record equine steps at walk and trot, when compared to video analysis, (2) if alternative positioning of these pedometers affected the accuracy of step detection when compared to video analysis. Method: Five horses each wearing a Yamax Digiwalk SW-200 (spring lever arm pedometer) and a Yamax Power Walker PW-610/611 (piezoelectric pedometer) positioned on the left foreleg (LF), left scapular (LS), chest (C), right scapular (RS) and right foreleg (RF) walked and trotted on a 20m circle 10 times on each rein to yield 100 results for each gait. Video recorded by GoPro Hero 3 Black edition camera positioned on the girth facing the forefeet using the following settings: 180 degree field of view, 720p, 120fps. Both visual and audio data were captured and recorded. Results: Kruskal-Wallis Test on the deviation from actual number of steps per unit for each type of pedometer and the position of the pedometer compared to the actual number of steps taken by both forelegs determined that there is a significant difference (H1= 340.31; P < 0.0001) between readings in walk and also in trot (H1 = 483.49; P < 0.0001). A further Kruskal-Wallis Test on the deviation from actual number of steps per unit for each type of pedometer and the position of the pedometer compared to the actual number of steps taken by individual forelegs determined that there is a significant difference (H = 403.36; p < 0.0001) at walk and also at trot (H = 477.10; p < 0.0001). Conclusion: In summary, the analysis of the pedometer data compared to video analysis indicate that pedometers are not useful for scoring forelimb movements in horses at walk and trot, regardless of positioning.

The purpose of this dissertation was to determine if the New Lifestyles NL-2000 (NL) and the Digi-Walker SW-200 (DW), waist-mounted devices, yield similar daily step counts as compared to the StepWatch 3 (SW), an ankle-mounted device, worn by adults and children in the free-living environment. For the first study, fifty-six adults (32.7 + 14.5 y) wore the devices for seven consecutive days. There were 20 normal weight, 18 overweight, and 18 obese participants. The NL and DW undercounted (pedometer error) similarly in the normal weight and overweight groups (-15.4% to -18.2%, respectively). However, the DW undercounted more than the NL in the obese group (-32.8% vs -23.9%, respectively). Stepwise regression revealed that both the NL and DW had more error (undercounted more) as a greater percentage steps were accumulated while walking slowly. The DW also had more error with greater BMI. Use of the DW in an obese population will result in twice the error as compared to a normal weight population and thus the DW should not be used to determine relationships between walking volume and adiposity For the second study, 74 children (13 ± 1.1 y) wore the same devices during one weekday. There were 33 normal weight, 21 overweight, and 20 obese participants. The error was determined for the NL and DW, and the values were similar in the normal weight and overweight groups (-10.8% to -15.4%, respectively). The DW undercounted more than the NL in the obese group (-27.3% vs -8.4%, respectively). The NL was very consistent regardless of BMI category, recording 89.1% (-10.8% error), 89.1% (-10.9% error), and 91.6% (-8.4% error) for the normal weight, overweight, and obese participants, respectively. Stepwise regression revealed that the DW undercounted more in participants with a high weight. Using the DW in obese children of this age group will result in significantly more undercounting when compared to normal weight children. The DW should not be used to determine relationships between walking volume and adiposity in this population. The NL undercounted by ~10%, regardless of BMI category.

Despite many advances in the design methods for compliant mechanisms, it is still not possible to know if a set of user-specifications has a solution. Furthermore, practical considerations such as failure limits and manufacturing limitations cannot be easily incorporated into existing methods. To address these issues, we have recently developed the concept of feasible stiffness and inertia maps. This thesis extends the concept of feasible maps and proposes another kind of maps that comprehensively depict the nonlinear kinetoelastostatic behaviour of compliant mechanisms. Feasible maps drawn as per user-specifications, with compliant mechanisms of the database overlaid on it, instantly inform the reader whether the specifications are feasible; whether the specifications are stringent; whether any mechanisms in the database meet the specifications, and whether any mechanism can be interactively modified to meet the specifications including size, strength and manufacturability. This thesis extends the earlier work on feasible maps by relaxing one condition that all beam segments in a compliant mechanism must retain their relative proportions. This is achieved by using size optimization. Thus, a certain degree of automation is brought into the procedure, which enhances the ease of use of the feasible maps. Illustrative examples are presented and implementation into a software is demonstrated. A major contribution of this work is the development of the concept of kinetoelastostatic maps of compliant mechanisms with fixed topology, shape, and relative proportions of beam segments in them. The map is drawn on a 2D plot using two non-dimensional quantities, one that captures the response of the mechanism and the other that combines the force, geometry, and material parameters. The map encloses a region that indicates the kinetoelastostatic capability of the mechanism. Another contribution of this work is the observation that the enclosed region can be parameterized using average slenderness ratio of the beam segments. The resulting curves help designers in assessing the capability and limits of a mechanism in terms of geometric advantage, mechanical advantage, normalized output displacement, inherent stiffness, etc. Numerous examples are presented to explain various uses of the non-dimensional maps.

A pragmatic method for designing compliant mechanisms is developed in this thesis, by selecting among existing mechanisms one that may be modified as required. This method complements existing techniques by answering questions of the existence and multiplicity of solutions for the given specifications of a practical problem. The premise for the method is a 2D map that juxta- poses the problem-specifications and the characteristics of compliant mechanisms in a database. The selection of the most suitable mechanisms is similar to Ashby's method of material selection. In our method, stuffiness, inertia, and the inherent kinematic characteristics of compliant mechanisms are analogous to material properties in Ashby's method. These characteristics capture the lumped behavior of compliant mechanisms in static and dynamic situations using spring-lever (SL) and spring-mass-lever (SML) models. The work includes the development of computation- ally efficient methods to compute the SL and SML model characteristics of single-input and single-output compliant mechanisms. Also developed in this work is a method to determine a feasible map by solving the governing equations of equilibrium and several inequalities pertaining to problem- specifications. The map helps not only in assessing the feasibility of the specifications but also in re-designing the mechanisms in predetermined ways to nd multiple solutions, all of which account for practical considerations. The method pays due attention to the overall size, strength considerations, manufacturability, and choice of material. It also enables minimal alterations of the problem-specifications when the user prefers a particular mechanism in the database. All these features are implemented in a web-based Java program with a graphical user interface that can be accessed at http://www.mecheng.iisc.ernet.in/ m2d2/CM design. Six case- studies that include micro machined inertial sensors, miniature valve mechanisms, ultra-sensitive force sensors, etc., are documented in detail to demonstrate the usefulness of the method in practice.