From gears to direct drive: Recent trends and opportunities in actuation

Abstract

Despite the maturity of classical industrial actuators with high reduction gearing, the new trend of more dynamic robots that require smaller weight has promoted the development of high torque electrical motors utilizing lower gear ratios - quasi-direct-drive actuation. The result has been actuators with reduced inertia, higher speeds, and generally reduced output impedance with better interaction capabilities. This development has renewed interest in novel gearing concepts, to achieve yet better systems in terms of efficiency, cost, and output torque density of the overall unit.

However, this trend also poses significant challenges. First, the lower gearing results in larger currents, and associated heating. This has sparked new development in high-performance motor drivers. Secondly, torque capacity and density suffer, which is why most applications of quasi-direct-drive actuation have been limited to smaller robots. A popular alternative, series-elastic actuation, does not suffer from these limitations but poses different challenges.

This workshop will explore these recent trends in robotic actuation. First, it will compare advantages and disadvantages of different approaches in different applications, including how to establish performance metrics/benchmarks for physical interaction performance. Second, it will explore novel approaches to address their shortcomings for the next generation of robots.

Topics of Interest

This is a full day workshop, which will comprise a mixture of presentations covering a number of relevant topics including:

    • Innovative low-ratio gearing and drives
    • Innovative high-ratio gearing and drives
    • High-voltage and -current drivers
    • Field-weakening
    • Over-modulation
    • Role of compliance in low/high-ratio actuation
    • (Active) Thermal management and cooling
    • Low-cost and open-source actuators and drivers
    • Multi-drive systems
    • Measuring/benchmarking physical interaction performance

Programme

Following the pre-recorded format, there are no time slots. The talks are however divided conveniently into sessions.

The panel discussion will take place during the live session, in the time slot indicated above. We invite all attendees to attend and contribute their questions and perspectives!

Session	Speaker	Title
Innovative gearing and drives
	Jack Schorsch	Speed Reducers: The Fundamental Element of Robot Performance (Youtube)
	Tom Verstraten	Compact Gearboxes for Modern Robotics (Youtube)
	Yasutaka Fujimoto	Bilateral Drive Gear - a Highly Backdrivable Reduction Gearbox for Robotic Actuators (Youtube)
	Wesley Roozing	Cost-effective robotic actuation for the real world (Youtube)
Motors and motor control
	Avik De	Operating at force, power, and thermal limits in electrically-actuated commercial legged robots (Youtube)
	Elliot Rouse	Modelling BLDC motors for the design of lightweight robotic systems: common mistakes and how to avoid them (Youtube)
	Oskar Weigl	Electronics and software for high performance motor drives for robotics: ODrive (Youtube)
	Navvab Kashiri	Thermal control for peak operation of robotics actuators
Application perspectives
	Sehoon Oh	High performance interaction control utilizing multiple sensors (Youtube)
	Jon Sensinger	Small but mighty – designing actuators for dynamic human-robot interactions (Youtube)
	Siavash Rezazadeh	How Quasi-Direct-Drive Actuators Can Help in Human-Like Bipedal Locomotion (Youtube)
	Luis Sentis	Versatile human-centered robots with ball screw electric actuators (Youtube)
	Kunio Kojima	Drive-trains design and low-level joint control of JAXON series (Youtube)
Panel discussion, Concluding remarks	Organisers, all	Live session in time slot indicated above

 

Youtube channel: IROS 2021 workshop: From gears to direct drive

 

Invited Speakers

Jack Schorsch IMSystems, The Netherlands Talk title: “Speed Reducers: The Fundamental Element of Robot Performance”		Avik De Harvard University and Ghost Robotics, US Talk title: “Operating at force, power, and thermal limits in electrically-actuated commercial legged robots”
Elliot Rouse University of Michigan, US Talk title: “Modeling BLDC motors for the design of lightweight robotic systems: common mistakes and how to avoid them”		Sehoon Oh DGIST, South Korea Talk title: “High performance interaction control utilizing multiple sensors”
Jon Sensinger University of New Brunswick, Canada Talk title: “Small but mighty – designing actuators for dynamic human-robot interactions”		Siavash Rezazadeh University of Denver, US Talk title: “How Quasi-Direct-Drive Actuators Can Help in Human-Like Bipedal Locomotion”
Luis Sentis University of Texas at Austin, US Talk title: “Versatile human-centered robots with ball screw electric actuators”		Kunio Kojima University of Tokyo, Japan Talk title: “Drive-trains design and low-level joint control of JAXON series”
Oskar Weigl ODrive Robotics Talk title: “Electronics and software for high performance motor drives for robotics: ODrive”

 

Organisers

Main Organizer

Wesley Roozing

Robotics and Mechatronics
Faculty of Electrical Engineering, Mathematics and Computer Science,
University of Twente, The Netherlands

Website

 

Co-organizers

Navvab Kashiri Department of Advanced Robotics, Instituto Italiano di Tecnologia, Genova, Italy Website		Tom Verstraten BruBotics, Universiteit Brussel, Belgium Website
Raphaël Guy Furnémont BruBotics, Universiteit Brussel, Belgium Website		Yasutaka Fujimoto Department of Electrical and Computer Engineering, Faculty of Engineering, Yokohama National University, Japan Website
Nikos Tsagarakis Department of Advanced Robotics, Instituto Italiano di Tecnologia, Genova, Italy Website		Stefano Stramigioli Robotics and Mechatronics, Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, The Netherlands Website

 

 

Technical Committees

This workshop has been endorsed by the following IEEE Robotics and Automation Society Technical Committees:

• IEEE/RAS TC on Mechanisms and Design
• IEEE/RAS TC on Telerobotics
• IEEE/RAS TC on Wearable Robotics
• IEEE/RAS TC on Performance Evaluation & Benchmarking of Robotic and Automation Systems
• IEEE/RAS TC on Humanoid Robotics
• IEEE/RAS TC on Rehabilitation and Assistive Robotics