Moving average based adaptive buffer for haptic media synchronization in telehaptics

Telehaptics is involved with various aspects of teleoperation applications. The problem of telehaptics of our concern in teleoperation is a delay variation on networks, or jitter delay. To solve the delay variation problem, a method of synchronization is required. This paper proposes the adaptive buffering control method for haptic media synchronization. The adaptive mechanism employs a moving average smoothing technique to calculate an expected delay in accordance with the delay variations resulting from the network traffics. Then, the expected delay is used to adjust the buffer size under a specified threshold. The idea of haptic media synchronization using a fixed buffer approach from our previous work is first carried out in the paper. Then, the proposed adaptive buffering control approach is explored in detail, including the methods to select the number of spans and to specify the threshold of adaptation. In addition, performance of the synchronization is verified by measuring the loss rate of haptic sequences for comparison between the fixed and adaptive buffering control approaches. According to the results, the adaptive buffer can preserve the loss of haptic sequences better than the fixed buffer approach when performing over the local, regional, and long distance network links under specified traffic conditions