Formulation of Flow Fluctuation Model of Tube Pump and its Suppression Control Based on Repetitive Control

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K18013
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Intelligent mechanics/Mechanical systems
• Research Institution: Matsue National College of Technology
• Principal Investigator: Katoh Kenichi 松江工業高等専門学校, 電子制御工学科, 講師 (70553600)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: チューブポンプ / 脈動抑制 / モデリング / 繰返し制御 / 実機検証

Outline of Final Research Achievements

Tube pump transfers liquid inside an elastic tube by moving rollers that squeeze the tube from the outside. This working principle enables a simple design free from watertight requirement, clean and contamination-free transfer due to the non-contact nature and easy re-configuration by changing the tube and the liquid at the same time. However, under the simplest implementation with U-shaped tube and revolving two rollers at constant speed, flow fluctuation is inevitable when one roller leaves the tube and negative pressure is generated by the tube restoration. In this research, the problem to reduce the flow fluctuation via open-loop control of the roller speed was considered. The ideal speed of each roller could be determined from the tube deformation model and realized and tested with two motors configuration. Tracking to the periodic reference speed was achieved by repetitive control. Then the same control strategy could be realized with single motor and non-circular gears.

Free Research Field

メカトロニクス，ロボティクス

Academic Significance and Societal Importance of the Research Achievements

チューブポンプを血液ポンプとして用いた場合，流路の強い流れや圧力変動が，赤血球の損傷や破壊を促進する可能性があるとの指摘がある．また，サンプリングレートが低いといった流量計を用いた場合には，計測精度の低下を招く恐れがある．エアチャンバやアキュムレータといった衝撃緩和装置の設置や送液タイミングをずらした複数のポンプの連動による方法などもあるが，頻繁に送液回路を更新する場合や固形物などを含む送液を行いたい場合などには，使用後の装置洗浄や取り替え，分岐・合流する特殊なチューブを使用する必要がある．本研究によって，これらの問題を多少なりとも緩和出来たのではないかと考える．