Dynamic Analysis and Control of a Portable Cherrypicker Available to Purchase

Cherrypickers are an important class of machines that can lift people to great heights. Understanding the dynamics and stability of these machines is crucial for efficient and safe operation. A dynamic model has been developed to capture the oscillatory dynamics of the machine as a function of the configuration and mass properties. Simulation studies reveal the complex dynamic behavior of the machine. In many cases, the oscillation of the endpoint bucket causes difficulties and dangers for the operators. An input-shaping controller has been added to the system to decrease the oscillatory dynamics. A portable cherrypicker is being developed for use in both education and research. The cherrypicker will be used as an experimental testbed in an advanced controls course at the Massachusetts Institute of Technology. The MIT students will use the machine to verify their theoretical models of the dynamic behavior, as well as evaluate control systems they develop to improve performance. Concurrently, students at the Georgia Institute of Technology will use the machine in teleoperation mode to conduct similar experiments. The MIT and Georgia Tech students will work together to conduct meaningful research on the cherrypicker testbed for their course projects. This paper describes the developments and results of the project to date.