Sökning: "dynamic joint stiffness"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden dynamic joint stiffness.

  1. 1. Controlling the dynamic characteristics of machining systems through consciously designed joint interfaces

    Författare :Constantinos Frangoudis; Cornel Mihai Nicolescu; Amir Rashid; Bulent Tasdelent; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Production; machine tool; machining system control; joint interfaces; JIM; stiffness; damping; vibrations; machining process; milling; turning; deflections; accuracy; dynamic response;

    Sammanfattning : The precision of machining systems is ever increasing in order to keep up with components’ accuracy requirements. At the same time product variants areincreasing and order quantities are decreasing, which introduces high demands on the capability of machining systems. LÄS MER

  3. 2. High dynamic stiffness nano-structured composites for vibration control : A Study of applications in joint interfaces and machining systems

    Författare :Qilin Fu; Cornel-Mihai Nicolescu; Per Nylén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vibration control; High dynamic stiffness; Metal matrix composite; Nano structures; Plasma enhanced chemical vapour deposition PECVD ; High power impulse magnetron sputtering HiPIMS ; Adiabatic; Machining; Regenerative tool chatter; Production Engineering; Industriell produktion;

    Sammanfattning : Vibration control requires high dynamic stiffness in mechanical structures for a reliable performance under extreme conditions. Dynamic stiffness composes the parameters of stiffness (K) and damping (η) that are usually in a trade-off relationship. This thesis study aims to break the trade-off relationship. LÄS MER

  4. 3. Joint Interface Effects on Machining System Vibration

    Författare :Qilin Fu; Cornel-Mihai Nicolescu; Tomas Beno; KTH; []
    Nyckelord :Joint Interface; Vibration; Damping; Chatter; Machining; Carbon NanoComposite; PECVD; HiPIMS; SRA - Production; SRA - Produktion; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

    Sammanfattning : Vibration problems are still the major constraint in modern machining processes that seek higher material removal rate, shorter process time, longer tool life and better product quality. Depending on the process, the weaker structure element can be the tool/tool holder, workpiece/fixture or both. LÄS MER

  5. 4. Biomechanical consequences of gait impairment at the ankle and foot : Injury, malalignment, and co-contraction

    Författare :Ruoli Wang; Elena Gutierrez-Farewik; Eva Broström; Eriksson Anders; Ilse Jonkers; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; muscle function; gait analysis; induced acceleration; foot kinematics; dynamic joint stiffness;

    Sammanfattning : The human foot contributes significantly to the function of the whole lower extremity during standing and locomotion. Nevertheless, the foot and ankle often suffer injuries and are affected by many musculoskeletal and neurological pathologies. LÄS MER

  7. 5. A sensory role for the cruciate ligaments : regulation of joint stability via reflexes onto the γ-muscle-spindle system

    Författare :Per Sjölander; Håkan Johansson; Uwe Windhorst; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Joint afferent; Mechanoreceptor; Cruciate ligament; Fusimotor neuron; reflex; muscle spindle afferent; motor control; cat;

    Sammanfattning : Reflex effects evoked by graded electrical stimulation of the posterior articular nerves (PAN) of the ipsi- and contralateral knee joints were investigated using both micro-electrode recordings from 7 - motoneurones and recordings from single muscle muscle spindle afferents. Spindle afferent responses were also recorded using natural stimulation of different types of receptors, to elucidate if the articular reflexes onto the y -motoneurones were potent enough to significantly alter the muscle spindle afferent activity. LÄS MER