Body-Machine Interface Enables People with Cervical Spinal Cord Injury to Control Devices with Available Body Movements: Proof of Concept

This study tested the use of a customized body-machine interface (BoMI) for enhancing functional capabilities in persons with cervical spinal cord injury (cSCI). The interface allows people with cSCI to operate external devices by reorganizing their residual movements. This was a proof-of-concept phase 0 interventional nonrandomized clinical trial. Eight cSCI participants wore a custom-made garment with motion sensors placed on the shoulders. Signals derived from the sensors controlled a computer cursor. A standard algorithm extracted the combinations of sensor signals that best captured each participant's capacity for controlling a computer cursor. Participants practiced with the BoMI for 24 sessions over 12 weeks performing 3 tasks: reaching, typing, and game playing. Learning and performance were evaluated by the evolution of movement time, errors, smoothness, and performance metrics specific to each task. Through practice, participants were able to reduce the movement time and the distance from the target at the 1-second mark in the reaching task. They also made straighter and smoother movements while reaching to different targets. All participants became faster in the typing task and more skilled in game playing, as the pong hit rate increased significantly with practice. The results provide proof-of-concept for the customized BoMI as a means for people with absent or severely impaired hand movements to control assistive devices that otherwise would be manually operated

Comparison of erosion rates in forest roads applying the WEPP model (Water Erosion Prediction Project) modified with reference to experimental measurements

O objetivo do trabalho foi testar o modelo WEPP (Water Erosion Prediction Project), através de comparações entre volume de enxurrada e perda de solo observados experimentalmente, provenientes dos segmentos de estradas florestais submetidas à chuva natural com inclinações de 1 e 7% e comprimentos de rampa de 20 e 40 m, e aqueles preditos pelo aplicativo, visando o desenvolvimento de um modelo brasileiro de predição de erosão em estradas florestais. Na determinação da quantidade do material erodido foram instalados tambores coletores, com capacidade de 209,25 litros, localizados na parte inferior das estradas, onde foram inseridas tubulações de PVC de 2 polegadas para coleta dos sedimentos provenientes da estrada propriamente dita. Nos tambores coletores foram feitos orifícios nivelados e perfeitamente iguais, posicionados a 0,65 m do fundo do primeiro e a 0,60 m do fundo do segundo, que funcionaram como um divisor Geib. Nas parcelas de 20 e 40 m de comprimento foram feitos cinco e sete orifícios, respectivamente, no primeiro e segundo tambores. O terceiro tambor foi utilizado para coletar o excedente da enxurrada proveniente do segundo tambor. Os tambores foram ligados em série, através de cano PVC de 2 polegadas. Os dados de volume e intensidade de precipitação diária foram obtidos com a instalação de pluviômetro e pluviógrafo no local. O período de coleta de dados foi de um ano, concentrando-se na época das chuvas. Posteriormente, os arquivos de clima, precipitação, solo, inclinação e comprimento do segmento foram introduzidos e adaptados ao modelo de predição de erosão WEPP com o propósito de testá-lo, visando a confecção de um modelo apropriado às condições brasileiras. _________________________________________________________________________________________ ABSTRACT: The objective of this work was to test the WEPP model (Water Erosion Prediction Project), by comparing experimentally observed runoff volume and soil loss in forest road segments under normal rainfall, with 1 and 7% slopes and lengths of 20 and 40 m, and those predicted by the WEPP, aiming to develop a Brazilian model of erosion prediction on forest roads. To determine the amount of eroded matter, 209.25 l capacity collector drums were placed on the lower level of the road segment. PVC pipes of 2 inches were connected to the drums to collect sediments from the road. Openings at the same height and size were made on the drums, located at 0.65 m from the bottom of the first drum and at 0.60 m from the bottom of the second drum, which functioned as a Geib divisor. In the 20 and 40 m long plots five and seven openings were made, respectively, on the first and second drums, with the third drum being used to collect the runoff excess from the second drum. The drums were connected in series through 2 inch - PVC pipes. Data of volume and intensity of daily precipitation were obtained by means of pluviometers and pluviographs. The period of data collection was one year, concentrated in the rainy season. Files on climate, precipitation, soil, slope and segment length were introduced and adapted to the WEPP model erosion prediction model to test it, aiming to elaborate a model suited to the Brazilian forest conditions