Coordination of multiple robot arms

Kinematic resolved-rate control from one robot arm is extended to the coordinated control of multiple robot arms in the movement of an object. The structure supports the general movement of one axis system (moving reference frame) with respect to another axis system (control reference frame) by one or more robot arms. The grippers of the robot arms do not have to be parallel or at any pre-disposed positions on the object. For multiarm control, the operator chooses the same moving and control reference frames for each of the robot arms. Consequently, each arm then moves as though it were carrying out the commanded motions by itself

Neural network modeling of nonlinear systems based on Volterra series extension of a linear model

A Volterra series approach was applied to the identification of nonlinear systems which are described by a neural network model. A procedure is outlined by which a mathematical model can be developed from experimental data obtained from the network structure. Applications of the results to the control of robotic systems are discussed

Comparison of joint space versus task force load distribution optimization for a multiarm manipulator system

It is often proposed that the redundancy in choosing a force distribution for multiple arms grasping a single object should be handled by minimizing a quadratic performance index. The performance index may be formulated in terms of joint torques or in terms of the Cartesian space force/torque applied to the body by the grippers. The former seeks to minimize power consumption while the latter minimizes body stresses. Because the cost functions are related to each other by a joint angle dependent transformation on the weight matrix, it might be argued that either method tends to reduce power consumption, but clearly the joint space minimization is optimal. A comparison of these two options is presented with consideration given to computational cost and power consumption. Simulation results using a two arm robot system are presented to show the savings realized by employing the joint space optimization. These savings are offset by additional complexity, computation time and in some cases processor power consumption

Technologies for learning: The right time at the right place

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87320/2/360_1.pd

How the Nintendo generation learns

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87319/2/361_1.pd

The Viability of Traditional Portuguese Olive Groves in the Alentejo Region under a Sustainable Development Framework

Portugal became self-sufficient in olive oil production in 2014 and produces 150% of its needs, which makes Portugal the world’s fourth-largest exporter (DeAndreis, 2022). Olive groves in Portugal were once estimated to be 70-80% low-input traditional type, but rapid intensification toward a predominantly intensive mode of agriculture has been extremely fast (Beaufoy, 2001, p. 22; Silveira et al., 2018, p. 248). The Alentejo region, despite its dry Mediterranean climate and a tradition of extensive, multi-functional agricultural systems, is now home to 85% of Portugal’s olive groves and responsible for 77% of the country’s olive oil production (Dawson, 2019; Silveira et al., 2018, p. 248). The traditional farm structure in olive oil production, with a majority of smaller size, unirrigated farms, and a few properties with more than 100 hectares, is therefore shrinking due to rapid change in the industry (Silveira et al., 2018, p. 259). The research objectives of this study are to present insights about the economic viability of traditional Portuguese olive groves utilizing a framework for sustainable development that includes economic, environmental, and social aspects. This research is based on a case study analysis of two semi-structured interviews with traditional olive grove farmers in Alentejo, supplemented with data from relevant literature about the environmental impacts of different types of olive groves in the region, as well as their varying production yields and costs. The main findings of the study were 1) the importance of certified organic production methods for traditional farmers that allow for valuable product differentiation and access to higher-paying consumers, and 2) the degree to which traditional olive producers were open to planting Portuguese varieties with less aggressive intensive methods (but nonetheless more intensive than the traditional olive grove), with the tradeoff of producing a higher quantity of olive oil and a fighting chance to preserve the national history and tradition that accompanies the unique tastes and aromas of native varieties

A study of World War II schizophrenic patients admitted to Bedford Veterans Administration Hospital from September 1, 1948 to September 1, 1949 with a service-connected neuropsychiatric disability.

Thesis (M.S.)--Boston Universit

Quick, where do the computers go?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87318/2/370_1.pd