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When performing trajectory planning for robotic applications, there are many aspects to consider, such as the reach conditions, joint and end-effector velocities, accelerations and jerk conditions, etc. The reach conditions are dependent on the end-effector orientations and the robot kinematic structure. The reach condition feasibility is the first consideration to be addressed prior to optimizing a solution. The ‘functional’ work space or work window represents a region of feasible reach conditions, and is a sub-set of the work envelope. It is not intuitive to define. Consequently, 2D solution approaches are proposed. The 3D travel paths are decomposed to a 2D representation via radial projections. Forward kinematic representations are employed to define a 2D boundary curve for each desired end effector orientation.

This study investigated driver glances while engaging in infotainment tasks in a stationary vehicle while surrogate driving: watching a driving video recorded from a driver’s viewpoint and projected on a large screen, performing a lane-tracking task, and performing the Tactile Detection Response Task (TDRT) to measure attentional effects of secondary tasks on event detection and response. Twenty-four participants were seated in a 2014 Toyota Corolla production vehicle with the navigation system option. They performed the lane-tracking task using the vehicle’s steering wheel, fitted with a laser pointer to indicate wheel movement on the driving video. Participants simultaneously performed the TDRT and a variety of infotainment tasks, including Manual and Mixed-Mode versions of Destination Entry and Cancel, Contact Dialing, Radio Tuning, Radio Preset selection, and other Manual tasks. Participants also completed the 0-and 1-Back pure auditory-vocal tasks.

Impacts have been analyzed in terms of degree of injury, head injury criterion (HIC), and average acceleration as a function of time for frontal impacts against the following surfaces: 1. Rigid flat surface-fractured cadaver skull. 2. Astroturf-head drop of football-helmeted cadaver. 3. Windshield penetrating impact of a dummy. 4. Airbag-dynamic test by human volunteers. It is concluded that the linear acceleration/time concussion tolerance curve may not exist and that only impacts against relatively stiff surfaces producing impulses with short rise times can be critical. The authors hypothesize that if a head impact does not contain a critical HIC interval of less than 0.015 s, it should be considered safe as far as cerebral concussion is concerned.

Path planning and re-planning for serial 6 degree of freedom (DOF) robotic systems is challenging due to complex kinematic structure and application conditions which affects the robot's tool frame position, orientation and singularity avoidance. These three characteristics represent the key elements for production planning and layout design of the automated manufacturing systems. The robot trajectory represents series of connected points in 3D space. Each point is defined with its position and orientation related to the robot's base frames or predefined user frame. The robot will move from point to point using the desired motion type (linear, arc, or joint). The trajectory planning requires first to check if robot can reach the selected part(s). This can be simply done by placing the part(s) inside the robot's work envelope. The robot's work envelope represents a set of all robots' reachable points without considering their orientation.

Children riding on the bed over the cab in campers can be injured in forward force collisions from striking the glazing material and/or being ejected through the opening. The two types of glazing commonly used are acrylic and laminated. A comparison of the performance of the two types of glazing in simulated forward force collisions at velocities up to 30 mph showed the acrylic material to pose threats of neck and back injury and the laminated material to result in lacerations. Ejections occurred with the acrylic that were not present with the laminated windshields when correct glazing techniques were used. With poor installation procedures, ejections occurred in both types of glazing materials. It is concluded that the best way to avoid injury is to prevent the child from riding in the over-the-cab bunk. If the child does ride there, his body axis should be positioned at an angle to the longitudinal axis of the vehicle.

Conventional 30 mil HPR laminated and wide-zone monolithic tempered windshields are compared on a safety performance basis from the stand-points of occupant injuries from frontal force collisions and injury or loss of control from breakage from high speed external impact of stones. All experiments were conducted with the windshields installed by conventional methods in an automobile. Occupant injury potential as measured by the Severity Index for brain damage at a 30 mph barrier impact simulation was approximately two times as high for the tempered as for the laminated windshields, although only one tempered windshield exceeded the recommended maximum value of 1,000. Severe lacerations resulted in all impacts in which the tempered glass broke. Less severe lacerations were found for the laminated windshield impacts at comparable speeds.

A comparative study of the safety performance of asymmetric and standard HPR windshields was conducted. The effect of increased interlayer thickness was also quantified. There were four different types of asymmetric windshields which had inner layer thicknesses of 0.8 to 1.5 mm and interlayer thicknesses of 0.76 and 1.14 mm. The experimental program consisted of both full scale sled tests and headform drop tests. A total of 127 vehicular impacts were carried out using a modified Volkswagen Rabbit. The test subject was a 50th percentile Fart 572 anthropomorphic test device. The asymmetric windshields were found to have a lower lacerative potential than that of the standard windshield. The best TLI value of 5.2 was provided by a 0.8 - 0.76 mm windshield at 60 km/h. That for the standard windshield was 7.7 at the same speed. All HIC values were less than 1,000 at 48 km/h.

An improved windshield with a special, thin, plastic inner surface attached to the inner surface of a three layer windshield similar to those used in the United States minimizes lacerations from occupant impact to the windshield during a collision. The plastic coats the sharp edges of the broken glass preventing or minimizing laceration. It was evaluated by comparing its laceration performance with that of a standard windshield in simulated barrier crashes at velocities up to 65 km/h. No lacerations resulted from impact to the Securiflex windshield at Barrier Equivalent Velocities up to 65 km/h. Substantial laceration resulted at velocities above 20 km/h with the standard windshield. It is concluded that the Securiflex windshield essentially eliminates lacerations in the particular vehicle involved at velocities up to at least 65 km/h.

Safety performance of an experimental windshield with a thin, chemically tempered inner pane is compared with the standard windshield and other experimental windshields. The chemically tempered windshield has a penetration velocity of 35 mph compared with 26 mph penetration velocity for the standard windshield and has lower peak head accelerations than other types used in the experiments. The windshield tested produces a bulge on impact, which decelerates the head over a long distance with low accelerations. The bulge or pocket is lined with particles that are less lacerative than the standard annealed glass.