The ability of technology to transmit multi-media is very dependent on compression techniques. In particular, lossy compression has been used in image compression (jpeg), audio compression (mp3) and video compression (mpg) to allow the transmission of audio and video over broadband network connections. Recently, the sense of touch, or haptics, is becoming more important, with its addition in computer games or in cruder applications such as vibrations in a cell phone. As haptic technology improves, the ability to transmit compressed force sensations becomes more critical. Most lossy audio and visual compression techniques rely on the lack of sensitivity in humans to pick up detailed information in certain scenarios. Similarly, limitations in the sensitivity of human touch could be exploited to create haptic models with much less detail and thus requiring smaller bandwidth. The focus of this paper is on the force thresholds of the human haptic system that can be used in a psychophysically motivated lossy haptic (force) compression technique. Most of the research in this field has measured the just noticeable difference (JND) of the human haptic system with a human user in static interaction with a stationary rigid object. In this paper, our focus involves cases where the human user or the object are in relative motion. An example of such an

This paper presents an enhanced haptic-enabled master-slave teleoperation system which can be used to provide force feedback to surgeons in minimally invasive surgery (MIS). One of the research goals was to develop a combined-control architecture framework that included both direct force reflection (DFR) and position-error-based (PEB) control strategies. To achieve this goal, it was essential to measure accurately the direct contact forces between deformable bodies and a robotic tool tip. To measure the forces at a surgical tool tip and enhance the performance of the teleoperation system, an optical force sensor was designed, prototyped, and added to a robot manipulator. The enhanced teleoperation architecture was formulated by developing mathematical models for the optical force sensor, the extended slave robot manipulator, and the combined-control strategy. Human factor studies were also conducted to (a) examine experimentally the performance of the enhanced teleoperation system with the optical force sensor, and (b) study human haptic perception during the identification of remote object deformability. The first experiment was carried out to discriminate deformability of objects when human subjects were in direct contact with deformable objects by means of a laparoscopic tool. The control parameters were then tuned based on the results of this experiment using a gain-scheduling method. The second experiment was conducted to study the effectiveness of the force feedback provided through the enhanced teleoperation system. The results show that the force feedback increased the ability of subjects to correctly identify materials of different deformable types. In addition, the virtual force feedback provided by the teleoperation system comes close to the real force feedback experienced in direct MIS. The experimental results provide design guidelines for choosing and validating the control architecture and the optical force sensor.

Automatic vehicle parallel parking design and its related concerns about safety improvement remain some of the heated problems for automatic land vehicular control. This paper presents the calculation process of a parallel parking car's path planning and the algorithm development for its motion design based on a fifthdegree polynomial curve. In addition to the proposed algorithm for automatic vehicle parking, the minimum horizontal distance allowed for parking between a car and a parking spot is also investigated. The preliminary results show that the fifth degree polynomial path planning and the algorithm are well applied to the automatic parallel parking problem.

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Designing haptic displays is one of the main challenges in force sensitivity are obtained for a user engaged in a task that creating virtual reality systems with the sense of touch. The design of is similar to Fitt's task [3] in a virtual environment. The effects the hardware and software of haptic interfaces depends critically on of force direction and the increment/decrement of the forces on the capabilities of the human haptic system. For example, force feed-force JND are also studied. back interfaces, due to inherent hardware limitations such as friction and actuator saturation, present forces to users in the case of interactions with a virtual environment which are only approximations of II. RELATED WORK the forces that they would feel if they were interacting with the real world. Thus, quantitative human studies are required to obtain the