Project description: The Integrated Bi-Stiffness Actuator (iBSA) [1,2] consists of modules such as motor, spring, brake, clutch, and link (see Fig. 1). With these modules, the actuator can be configured in various operating modes. It also consists of various sensors which enable multiple sensor feedback. The objective is to develop a Modular Low-level Control Framework for Modular Actuator with Multiple Sensor Feedback. By exploiting the modular structure characteristic of the BSA, the effects of each element such as link decoupling, the performance of the elastic element, stiffness brake, and motor control can be tested independently. Moreover, other factors such as friction, hysteresis, effects of coupling and mechanical play between parts, and the effect of switching which creates instantaneous change in velocity can also be analyzed and their effect reduced through control at low-level. The end goal is to integrate the controllers into a generalized framework for the combined system.

Prerequisites:

• Master-level studies in Robotics, Electrical Engineering, Mechanics, Electronics, Computer Science
• Background in robotics with basic understanding of manipulator kinematics and dynamics.
• Dynamic systems modeling techniques
• Background in hardware development and system integration
• Good programming skills with Matlab, Python, and C++
• Working skills in the Ubuntu operating system
• Knowledge of parameter estimation algorithms and sensor fusion frameworks such as Kalman filter is a plus
• Experience in design of experiments is a plus

1. E. P. Fortunić, M. C. Yildirim, D. Ossadnik, A. Swikir, S. Abdolshah and S. Haddadin, “Optimally Controlling the Timing of Energy Transfer in Elastic Joints: Experimental Validation of the Bi-Stiffness Actuation Concept,” in IEEE Robotics and Automation Letters, vol. 8, no. 12, pp. 8106-8113, Dec. 2023, doi: 10.1109/LRA.2023.3325782.
2. D. Ossadnik et al., “BSA - Bi-Stiffness Actuation for optimally exploiting intrinsic compliance and inertial coupling effects in elastic joint robots,” 2022 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Kyoto, Japan, 2022, pp. 3536-3543, doi: 10.1109/IROS47612.2022.9981928.

To apply, send your CV, cover letter, and supporting documents to Samuel Kangwagye (s.kangwagye(at)tum.de).

Chair of Robotics Science and Systems Intelligence

Munich Institute of Robotics and Machine Intelligence

Technical University of Munich