Research
ckBot: Self-Assembly after Explosion |
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 | This project introduces a new challenge problem: designing robotic systems to recover after disassembly from high-energy events and a first implemented solution of a simplified problem. The Self-reassembly After Explosion (SAE ) problem involves a system putting itself back together after being exploded. Explosion in this context is defined as the rapid, randomized disassembly of a system from a high-energy event. Vision-based guided localization is used here for self-reassembly. Integration of various communication schemes (CAN-BUS, local IR) are incorporated at the various states of the reassembly sequence (e.g., localization, docking, walking). | ||
ckBot: Dynamic Rolling |
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 | Reconfigurable modular robots have the ability to use different gaits and configurations to perform various tasks. A rolling gait is the fastest currently implemented gait available for traversal over level ground and shows dramatic improvements in efficiency. In this work, we analyze and implement a sensor-based feedback controller to achieve dynamic rolling for a loop robot. The robot senses its position relative to the ground and changes its shape as it rolls. This shape is such that its center of gravity is maintained to be in front of its contact point with the ground, so in effect the robot is continuously falling and thus accelerates forward. The highest velocity achieved in this work is 26 module lengths per second (1.6m/s) which is believed to be the fastest gait yet implemented for an untethered modular robot | ||
Embedded Isomorphic Configuration Recognition for ckBot systems |
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This research involves embedded isomorphic configuration recognition
for ckBot systems. Given that each ckBot module is assigned a unique
node ID, a centralized algorithm uses the eigenvalues (graph spectrum)
of adjacency matrices to determine if a given structure is recognized
as a useful one in library of configurations and corresponding gaits.
If a match is found, an efficient permutation routine finds the exact
node ID assignment so that correct controls are assigned to each module
within the system.
This algorithm is currently being generalized to be hierarchical, so that modules within clusters as well as inter-clusters arrangements are isomorphic. Integration of a decentralized, fault-tolerant system with structural isomorphism is a related area of research. In particular, simulations of Byzantine fault tolerant algorithms that function on majority rules when sub-critical numbers of modules are faulty or unable to communicate with the system is a project in development. | ||
Dynamic Planning |
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 | The scope of this project is to develop a robust locomotive gait planner for the ckBot modules. In collaboration with Rice University, this project aims to make use of dynamic planning algorithms to discover new methods of module locomotion. The ultimate objective of this project is to develop a goal oriented gait planner that can create successful gaits for virtually any configuration of modules with any possible goal state. | ||
External Actuation for a Modular Robotic System |
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A significant challenge in the field of Modular Self-reconfigurable Robotics (MSR)
is to develop systems with a large number of modules that are orders of magnitude smaller
than current MSR modules (typically on the order of 5-10cm on a side.) One factor that inhibits
reduction in module size is bulk of the main actuator that allows the module to move itself or
another module to another position in the lattice or chain robotic structure.
The use of External Actuation provides one possible solution to this physical limitation by removing the need for a main actuator. The energy required to reconfigure of a module comes from the environment (external to the module) in some form such as vibration or oscillation of the system. The main goal of the project is to develop systems that can reconfigure using External Actuation and move towards creating smaller modules in larger quatities. | ||
