Reducing the conservatism of the time domain passivity approach through consideration of energy reflection in delayed coupled network systems

Abstract

The Time Domain Passivity Approach (TDPA), a method to inject adaptive damping to satisfy the passivity condition in realtime, has emerged as a powerful tool to stabilize coupled network systems with/without communication delay, such as haptic and teleoperation systems, due to its simplicity and effectiveness. However, we found that the conventional TDPA has unnecessary conservatism especially in delayed coupled network systems due to direction dependent energy calculation and dissipation. In this paper, we propose a new time domain passivity approach with reduced conservatism by considering the energy reflection from an energy storage element in the network. The method is generally formulated with a delayed 2-port network system including an energy storage element and implemented to a teleoperation system. The proposed method is experimentally tested and a comparison with the conventional TDPA reveals improved kinesthetic coupling and transparency in terms of position tracking and force reflection.

Robotics and AI for Teleoperation, Tele-Assessment, and Tele-Training for Surgery in the Era of COVID-19: Existing Challenges, and Future Vision

“…Due to the concerns of safety the existing commercialized telerobotic surgical systems, such as the da Vinci surgical system, do not enable force reflection, even though it is known that force reflection can significantly increase the quality of surgery by providing a much higher situational awareness for surgeons. Although a number of stabilizers and control algorithms have been reported in the literature, the existing algorithms result in deviation of motion tracking and force reflection, which reduces the accuracy of surgery and is often not acceptable (Artigas et al, 2010;Chawda and Omalley, 2015;Atashzar et al, 2017b;Panzirsch et al, 2019;Singh et al, 2019). Besides stability, instrumentation is another challenge.…”

“…Both techniques stabilize the system; however, stabilization comes at the cost of compromising transparency. Considerable research has been done to improve the performance of teleoperation (Artigas et al, 2010;Chawda and Omalley, 2015;Atashzar et al, 2017b;Panzirsch et al, 2019;Singh et al, 2019), but the proposed stabilization methods are still far from ideal. The discussion above clarifies some of the technical challenges creating obstacles to realizing high-fidelity haptics-enabled teleoperated surgery.…”

QoS Provisioning: Key Drivers and Enablers Toward the Tactile Internet in Beyond 5G Era

“…To provide a feasible solution for position drifts while improving QoE under various network unreliability, such as delay, jitter, packet loss, [203] considered cross-traffic data, stability, and transparency problems. They proposed a hybrid solution coupling energy reflection-based TDPA [206] and PDb to trade-off between haptic packet rate and teleoperation quality. Their proposed time-triggered PDb approach with energy-based TDPA dramatically reduced packet rate from 1000 to 100 packet/second with 150 ms delay.…”

An Ecosystem for Heterogeneous Robotic Assistants in Caregiving: Core Functionalities and Use Cases

“…Despite the market maturity, safety of the persons in the robot environment but also of the human operator in the control center remain of utmost priority in the development process. Additional safety measures include the observation of the quality in the communication channel, passivity-based handling of interaction forces, and the overall control stability despite time delay [31]. Still, delay itself is the limiting factor for human perception and performance.…”