| 1. |
- Darup, Moritz Schulze, et al.
(författare)
-
Towards real-time ADMM for linear MPC
- 2019
-
Ingår i: 2019 18th European Control Conference, ECC 2019. - 9783907144008 ; , s. 4276-4282
-
Konferensbidrag (refereegranskat)abstract
- We present a novel predictive control scheme for linear constrained systems that uses the alternating direction method of multipliers (ADMM) for online optimization. In contrast to existing works on ADMM-based model predictive control (MPC), we only consider a single ADMM-iteration in every time step. The resulting real-time ADMM scheme is tailored for embedded and fast MPC implementations. The main difference to existing MPC schemes based on real-time iterations is that the proposed controller allows to include state and input constraints of the system. The paper derives the dynamics of the resulting closed-loop system, identifies important parameters of the real-time ADMM, and compares its performance to classical MPC.
|
|
| 2. |
- Kim, Junsoo, et al.
(författare)
-
Asymptotic Stabilization over Encrypted Data with Limited Controller Capacity and Time-varying Quantizer
- 2022
-
Ingår i: 2022 IEEE 61ST CONFERENCE ON DECISION AND CONTROL (CDC). - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 7762-7767
-
Konferensbidrag (refereegranskat)abstract
- We consider a problem of implementing dynamic controllers over encrypted data for asymptotic stabilization of closed-loop systems. Though a time-varying quantizer is used and it can be infinitesimally fine with time, a major issue is that the underlying space for encrypted messages is unavoidably finite and the controller receives a limited amount of quantized data. To resolve this issue, the proposed method takes advantage of the state matrix consisting of integers, which enables the controller to generate only lower bits of the same output without computing the upper bits. Whenever a portion of the upper bits of output has converged, the computation scope can be moved further lower, receiving only lower bits of the measurement. The quantization is scheduled and the size of the message space is predetermined from the convergence rate, so that the feedback input is restored from the outcome of the lower bits, no matter how fine quantization is performed in the end. As a consequence, asymptotic stabilization can be achieved by encrypted operation, despite the limited controller capacity.
|
|
