Open Source Cultivator for a Motorcycle

https://www.embrapa.br/en/busca-de-publicacoes/-/publicacao/1143149/passos-para-a-construcao-de-cultivadores-acionados-por-motocicleta

I do not know how strong their english is, but below is the contact of the authors (public information taken from here: https://portaldxp-p.sede.embrapa.br/equipe/-/empregado/):

José Geraldo da Silva josegeraldo.silva@embrapa.br He has experience in the field of Agricultural Engineering, with a focus on Machine Design, working primarily on the following areas: grain loss, performance, mechanization, equipment and seed loss

Reginaldo Aparecido de Bastos reginaldo.bastos@embrapa.br Not enough details

Adriano Stephan Nascente adriano.nascente@embrapa.br Plant Breeding and Use of Multifunctional Microorganisms in Agricultural Systems, Crop Management and Cultural Practices

Agostinho Dirceu Didonet agostinho.didonet@embrapa.br He has experience in the field of botany, focus on plant physiology, working primarily growth and development, production physiology, ecophysiology, temperature and grain yield components, plant-microorganism interactions, agroecology and rural extension

I couldn't find more details for Rogério de Araújo Almeida unfortunately