Visual assessment of a real-time system design: a case study on a CNC controller

In this paper we describe our experiments on a realtime system design, focusing on design alternatives such as scheduling jitter, sensor-to-output latency, intertask communication schemes and the system utilization. The prime objective of these experiments was to evaluate a real-time design produced using the period calibration method [2] and thus identify the limitations of the method. We chose a computerized numerical control (CNC) machine as our target real-time system and built a realistic controller and a plant simulator. Our results were extracted from a controlled series of more than hundred test controllers obtained by varying four test variables. This study unveils many interesting facts: (1) average sensor-to-output latency is one of the most dominating factors in determining control quality; (2) the effect of scheduling jitter appears only when the average sensor-to-output latency is sufficiently small; and (3) loop processing periods are another dominating factor of perfor...

• Type: Conference
• Year: 1996
• Where: RTSS
• Authors: Namyun Kim, Minsoo Ryu, Seongsoo Hong, Manas Saksena, Chong-Ho Choi, Heonshik Shin
• Keywords: Average Sensor-to-output Latency, Control Systems, Period Calibration Method, RTSS 1996, Sensor-to-output Latency