Reaction Force Observer based Torque Control

Yıl 2021, , 1629 - 1635, 01.12.2021

Erim Can Özçınar Regaip Barkan Uğurlu

https://doi.org/10.2339/politeknik.848036

Cited By: 1

Öz

In this article, a reaction force observer-based torque controller was designed and experimentally implemented to a non-backdrivable actuator unit. Torque control is of importance when considering physical human-robot interaction and researchers usually use torque sensors or custom-built torsional springs. These elements lead to relatively more complicated systems and increase the total weight. In contrast, reaction force observers can estimate external forces acting on the system and thus enable torque control with no need of torque sensing. The estimation process performs better for backdrivable systems, therefore, its implementation to non-backdrivable systems, e.g., systems with a gear ratio of 1:100, is limited. To remedy this issue, a reaction force observer-based torque controller was designed and implemented. As a result, experimental data showed that reaction force observer leads to favorable torque control performance when supported with friction compensation.

Anahtar Kelimeler

Torque control, reaction force observer, disturbance observer, friction compensation

Tepki Kuvveti Gözetleyicisi Tabanlı Tork Kontrolü

Öz

Bu makalede tepki kuvveti gözetleyicisi baz alınarak bir tork kontrolcüsü tasarlanmış ve etkinliği geri sürülebilir olmayan bir eyleyici ünitesi üzerinde deneysel olarak sınanmıştır. Fiziksel insan-robot etkileşimi için son derece yüksek bir öneme haiz olan tork kontrolü için genellikle tork sensörleri veya özel olarak üretilen burulma yayları kullanılmaktadır. Bu ekipmanlar ise hem sistemi karmaşıklaştırmakta, hem de toplam ağırlığı arttırmaktadır. Tepki kuvveti gözetleyici yöntemi ise sisteme etkiyen dış kuvvetleri kestirebilmekte ve bu sayede sensör kullanmaksızın tork kontrolünün uygulanmasına olanak sağlamaktadır. Bu kestirim genellikle geri sürülebilir sistemlerde daha sağlıklı işlemektedir, dolayısıyla geri sürülemeyen sistemlerde (örneğin 1:100 dişli oranlı sistemler) uygulaması sınırlıdır. Bu noktadan hareketle, geri sürülemeyen bir sistem için tepki kuvveti gözetleyicisi bazlı bir tork kontrolü tasarlanmış ve uygulanmıştır. Sonuç olarak sürtünme kompanzasyonu sağlandığında tepki kuvveti gözetleyicisinin tork kontrolünü sağlayabildiği deneysel bulgular ışığında saptanmıştır.

Anahtar Kelimeler

Tork kontrolü, tepki kuvveti gözetleyici, bozunum gözetleyici, sürtünme kompanzasyonu

Kaynakça

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