Post-project assessment and follow-up support for community managed rural water systems in Panama

The Environmental Health (EH) program of Peace Corps (PC) Panama and a non-governmental organization (NGO) Waterlines have been assisting rural communities in Panama gain access to improved water sources through the practice of community management (CM) model and participatory development. Unfortunately, there is little information available on how a water system is functioning once the construction is complete and the volunteer leaves the community. This is a concern when the recent literature suggests that most communities are not able to indefinitely maintain a rural water system (RWS) without some form of external assistance (Sara and Katz, 1997; Newman et al, 2002; Lockwood, 2002, 2003, 2004; IRC, 2003; Schweitzer, 2009). Recognizing this concern, the EH program director encouraged the author to complete a postproject assessment of the past EH water projects. In order to carry out the investigation, an easy to use monitoring and evaluation tool was developed based on literature review and the author’s three years of field experience in rural Panama. The study methodology consists of benchmark scoring systems to rate the following ten indicators: watershed, source capture, transmission line, storage tank, distribution system, system reliability, willingness to pay, accounting/transparency, maintenance, and active water committee members. The assessment of 28 communities across the country revealed that the current state of physical infrastructure, as well as the financial, managerial and technical capabilities of water committees varied significantly depending on the community. While some communities are enjoying continued service and their water committee completing all of its responsibilities, others have seen their water systems fall apart and be abandoned. Overall, the higher score were more prevalent for all ten indicators. However, even the communities with the highest scores requested some form of additional assistance. The conclusion from the assessment suggests that the EH program should incorporate an institutional support mechanism (ISM) to its sector policy in order to systematically provide follow-up support to rural communities in Panama. A full-time circuit rider with flexible funding would be able to provide additional technical support, training and encouragement to those communities in need.

ANKLE IMPEDANCE AND ANKLE ANGLES DURING STEP TURN AND STRAIGHT WALK: IMPLICATIONS FOR THE DESIGN OF A STEERABLE ANKLE-FOOT PROSTHETIC ROBOT

During locomotion, turning is a common and recurring event which is largely neglected in the current state-of-the-art ankle-foot prostheses, forcing amputees to use different steering mechanisms for turning, compared to non-amputees. A better understanding of the complexities surrounding lower limb prostheses will lead to increased health and well-being of amputees. The aim of this research is to develop a steerable ankle-foot prosthesis that mimics the human ankle mechanical properties. Experiments were developed to estimate the mechanical impedance of the ankle and the ankles angles during straight walk and step turn. Next, this information was used in the design of a prototype, powered steerable ankle-foot prosthesis with two controllable degrees of freedom. One of the possible approaches in design of the prosthetic robots is to use the human joints’ parameters, especially their impedance. A series of experiments were conducted to estimate the stochastic mechanical impedance of the human ankle when muscles were fully relaxed and co-contracting antagonistically. A rehabilitation robot for the ankle, Anklebot, was employed to provide torque perturbations to the ankle. The experiments were performed in two different configurations, one with relaxed muscles, and one with 10% of maximum voluntary contraction (MVC). Surface electromyography (sEMG) was used to monitor muscle activation levels and these sEMG signals were displayed to subjects who attempted to maintain them constant. Time histories of ankle torques and angles in the lateral/medial (LM) directions, inversion-eversion (IE), and dorsiflexionplantarflexion (DP) were recorded. Linear time-invariant transfer functions between the measured torques and angles were estimated providing an estimate of ankle mechanical impedance. High coherence was observed over a frequency range up to 30 Hz. The main effect of muscle activation was to increase the magnitude of ankle mechanical impedance in all degrees of freedom of the ankle. Another experiment compared the three-dimensional angles of the ankle during step turn and straight walking. These angles were measured to be used for developing the control strategy of the ankle-foot prosthesis. An infrared camera system was used to track the trajectories and angles of the foot and leg. The combined phases of heel strike and loading response, mid stance, and terminal stance and pre-swing were determined and used to measure the average angles at each combined phase. The Range of motion (ROM) in IE increased during turning while ML rotation decreased and DP changed the least. During the turning step, ankle displacement in DP started with similar angles to straight walk and progressively showed less plantarflexion. In IE, the ankle showed increased inversion leaning the body toward the inside of the turn. ML rotation initiated with an increased medial rotation during the step turn relative to the straight walk transitioning to increased lateral rotation at the toe off. A prototype ankle-foot prosthesis capable of controlling both DP and IE using a cable driven mechanism was developed and assessed as part of a feasibility study. The design is capable of reproducing the angles required for straight walk and step turn; generates 712N of lifting force in plantarflexion, and shows passive stiffness comparable to a nonload bearing ankle impedance. To evaluate the performance of the ankle-foot prosthesis, a circular treadmill was developed to mimic human gait during steering. Preliminary results show that the device can appropriately simulate human gait with loading and unloading the ankle joint during the gait in circular paths.