Performance Evaluation

Extensive testing of the artificial foal was conducted to ensure that this manikin met the design criteria.  As stated in the objectives, the three main requirements of this project are that the foal design is life-like, especially in the motion of its joints, it has features that can be identified by touch, and it also has a water-resistant, durable coating.

The testing of the artificial foal consisted of four stages which focused on the specific design objectives:

• measurement of body structures and weight

• a joint test

• a wash test

• approval by Dr. Werner, the design sponsor

These tests ensured that the foal manikin fits the objectives set forth by the sponsor.

            Before beginning the four stages of testing, the team members obtained weight and body measurements of the artificial foal. The weight was measured three times on a typical bathroom scale. The result was a weight of 31 ± 2 pounds. The body structure measurements are included in Table 1.

 Table 1: Measurements

                *These measurements are for the smallest and largest width for the structure

             The joint test was conducted to investigate the integrity of the connections and also to determine if the limbs move in the correct orientation.  This test was divided into two parts.  The first step examined each joint to conclude that the limbs bend only in directions that are true to life. Each team member was assigned a joint to test its ability to bend. The member flexed and extended the joint 20 times, ensuring that the connections were sturdy and the movement-limiting straps could withstand the force. This test was repeated with the legs attached to the body and the skin covering the joints. It was concluded that flexing the joints numerous times did not affect the skin, nor did the skin affect the bending of the joints.

The ability of the joints to flex and extend was measured using a protractor shown in Table 2.  Each of the measurements was taken three times. The zero position was set at the point where the joint is fully extended. The flexed measurement corresponds to the joint when it is bent in the proper orientation. The extended position corresponds to the joint when it is experiencing a force in the direction opposite to the way it is supposed to bend. In other words, it is when the joint is hyper-extended.  Each joint location is explained in Figure 1.

Table 2: Joint Angles

 The angle of rotation of the shoulder and hips was also measured using a protractor and the results are shown in Table 3.  When the shoulder is perpendicular to the body, the angle of rotation was set at 90 degrees. Moving the leg forward, towards the head, corresponds to 0 degrees; moving the leg backwards, toward the tail, corresponds to 180 degrees.

Table 3: Angle of Rotation for Shoulder and Hip

 The second step was to determine if the manikin can be manipulated into all of the possible positions that may occur during the birthing process. The following illustrations provided by the design sponsor represent the positions commonly encountered during birth. Photographs of the foal manikin corresponding to the various positions are also provided. From this experiment, it was concluded that the artificial foal can be manipulated into the required positions, thus satisfying this design requirement.

The wash test was designed to guarantee that the outer coating of the manikin is water-resistant and capable of withstanding lubricants and mild detergents that will be applied to this surface.  Water-resistant is defined as the ability to prevent the penetration of water by www.m-w.com. Typically, water-resistant objects are not meant to be submerged. During this testing, the hooves were not yet attached. Care was taken to prevent water from entering these openings by wrapping plastic bags around the bottom of each leg and securing the bags with duct tape.

This test was further divided into three parts.  The first part was to determine if the skin is water resistant.  The foal manikin was gently sprayed with water from a hose for one minute while resting on its stomach.  After one minute, it was examined to identify if water had entered under the skin. This was repeated 5 times.  The manikin was then placed on its back and sprayed with water for one minute, 5 times total.  Once again, it was examined to identify if water had entered the inner structures.  After the fifth rinse, the model was towel dried and weighed on a typical bathroom scale.  The foal manikin’s weight was consistent with the initial weight of 31 pounds, so it was concluded that a significant amount of water had not entered the manikin. The results of this test showed that when spraying the foal mannequin with water from a hose, water does not appear to enter beneath the skin. This test proved that the foal manikin is water resistant.  

The second step consisted of applying a lubricant.  After application, the manikin was not washed for a 15 minutes. After this time period, the lubricant was rinsed off with water from a hose and a cloth.  The skin was then examined to determine if it had reacted with the lubricant.  Each of the movable joints was flexed 5 times to ensure that the skin was still intact and unaffected by the lubricant.  This sequence was repeated 5 times and the results recorded.  This test showed that the skin does not react with the lubricant.

The third step included washing the manikin with a mild detergent, once again to identify if there was a reaction with its skin.  The model was lubricated and then sprayed with water from a hose.  The mild detergent was applied to all surfaces and was rinsed off with a hose and cloth one minute later. This series of steps were repeated 5 times, with the skin examined and results recorded after each step.  This test showed that the skin is not affected by the detergent.

            The final test in analyzing the performance of the artificial foal was presenting it to Dr. Werner, the design sponsor.  During this meeting, he had the opportunity to inspect the foal to determine if it met the design criteria.  Dr. Werner lifted the body to ensure it was the appropriate weight and size. He inspected each joint to test the flexibility and range of motion of the legs. Dr. Werner also manipulated the foal mannequin into several positions, pointing out that movement was satisfactory. Because the design sponsor did not have suggestions for improvement, the only feature left to add were the hooves.