Aliakbar Alamdari

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High mobility, maneuverability and obstacle surmounting capabilities are highly desirable features for rough-terrain locomotion systems. In past work, we examined kinetostatic optimization of candidate articulated leg-wheel subsystem designs (based on the four-bar mechanism) for enhancing locomotion capabilities of land-based vehicles. Our goal was to: (i)(More)
The Articulated Wheeled Vehicle (AWV) paradigm examines a class of wheeled vehicles where the chassis is connected via articulated chains to a set of ground-contact wheels. Actively-or passively-controlled articulations can help alter wheel placement with respect to chassis during locomotion, endowing the vehicle with significant reconfigurability and(More)
The Leg-Wheel-Vehicle paradigm offers remarkable and diverse opportunities for creation of mobile and maneuverable terrestrial locomotion systems. However, this capability needs to be unlocked by careful design and control of the individual articulations, the sub-chains and the systems as a whole. Viewing leg-wheel vehicles as another class of(More)
This paper examines the design, analysis and control of a novel hybrid articulated-cable parallel platform for upper limb rehabilitation in three dimensional space. The proposed lightweight , low-cost, modular reconfigurable parallel-architecture robotic device is comprised of five cables and a single linear actuator which connects a six degrees-of-freedom(More)
Assisted motor therapies play a critical role in enhancing the functional musculoskeletal recovery and neurological rehabilitation. Our focus here is to assist the performance of repetitive motor-therapy of the human lower limbs – in both the sagittal and frontal planes. Hence, in this paper, we develop a lightweight , reconfigurable hybrid(More)
Traditional kinematic analysis of manipulators, built upon a deterministic articulated kinematic modeling often proves inadequate to capture uncertainties affecting the performance of the real robotic systems. While a probabilistic framework is necessary to characterize the system response variability, the random variable/vector based approaches are unable(More)
Leg-wheel architectures for locomotion systems offer many advantages, not the least of which is reconfigurability of wheel-axle with respect to the chassis. Thus, locomotion systems with multiple leg-wheels now permit enormous reconfigurabil-ity of the chassis frame with respect to the ground frame. We seek to systematically exploit this ability to(More)
In this paper, we generalize our random matrix based (RM-based) uncertainty model for manipulator Jacobian matrix to the dynamic model of the robotic systems. Conventional random variable based (RV-based) schemes require a detailed knowledge of the system parameters variation and may be not able to fully characterize the uncertainties of the complex dynamic(More)
Input shaping control techniques have proven to be very effective in improving performance and lowering actuation requirements for Linear Time-Invariant (LTI) systems. However, deployments tend to be very sensitive to variation of the system natural frequencies and damping ratios. This limits the application of input shaping schemes in the nonlinear systems(More)
Articulated Wheeled Vehicles (AWVs) offer superior uneven terrain traver-sal capabilities by virtue of the superior reconfigurability within their articulated structure. However, this capability can be realized only at the price of increased actuation-based equilibration, oftentimes solely to support the grav-itational loading. Hence, the simultaneous(More)