Case Study: Shadow Robot

Image courtesy of Shadow Robot: The Shadow Dexterous Hand Series

Robotics Solutions--Giving a Helping Hand

Robots are being adopted at a rapid rate within many varied sectors. Industry challenges once thought too big to solve are now a reality with robotics. Early on, one company had a vision and drive too big to fail—Shadow Robot. Pioneers in the industry, they’ve been on the cutting-edge of robotics for over a decade, delivering customized robotics solutions around the world. 

Image courtesy of Shadow Robot: The Shadow Dexterous Hand Series

Product: Shadow Dexterous Hand Robot

Among their award-winning robots, is the Shadow Dexterous Hand. It’s a humanoid hand-and-arm system that provides human-level dexterity at a distance, or remotely, which is referred to as teleoperation. The system tracks human user fingertip positions and orientations relative to the palm, and this next generation robot hand system touts unmatched dexterity.

Hailed among top researchers, the teleoperation robot system gets particular attention when the work environment is unsafe, impractical, expensive, or undesirable. Shadow Robot categorizes these environments into six areas that start with the letter “D,” including work that’s Dull, Dirty, Dangerous, Delicate, Distant, or Difficult. 

Examples of work that fall into the six “D’s” include: repetitive tasks on assembly lines, mining, cleaning, fine assembly work, remote maintenance, nuclear decommissioning, bomb disposal, or work in areas difficult to access. 

Finding the Right Motion Tracking Solution

With a wide variety of potential use cases in mind, and the intention to do good with robots, Shadow Robot set out to find the right tracking solution. Some of the key, next generation features needed to take their product to the next level included real-time tracking, enabling finger pivoting, finger sliding and finger gaiting, and independent side-to-side finger movement. Shadow Robot faced three main challenges when assessing motion tracking technologies for integration:

1.    Requirements for high-fidelity tracking with low latency
2.    Line-of-sight occlusions
3.    Sensor size

Image courtesy of Shadow Robot: The Shadow Dexterous Hand Series

Challenge #1: High-Fidelity Tracking Capability and Low Latency

The human hand is a highly adaptive extremity, and the robot hand needed to truly replicate the quick dexterity of its human hand counterpart. High-fidelity tracking, a high level of precision, and near-zero lag time, (otherwise known as latency) were critical. Most tracking systems are plagued by latency issues, which can limit applications in robotics, VR (virtual reality) and AR (augmented reality). 

Challenge #2: Line-of-Sight Occlusions

An object, person, or equipment can easily block the line-of-sight in tracking applications, causing delays in tracking data. For example, with hand and finger tracking, a hand that moves in the wrong angle or gets out of range, runs the risk of motion tracking disruption. Line-of-sight occlusions are a common issue with optical tracking technologies (otherwise known as camera-based tracking). This can pose a challenge for some applications. 

Challenge #3: Sensor Size

Finding sensors small enough to fit into a glove without constricting or obstructing finger movement was key. Motion tracking sensors needed to be micro-sized, flexible and deliver reliable, repeatable results. 

The Solution--Polhemus AC Electromagnetics Motion Tracking Technology

Shadow Robot tested several motion tracking technologies to vet the pros and cons of each. After trial and error, they integrated AC electromagnetics, by Polhemus, the Experts in Motion Tracking™. All three challenges were resolved with the Polhemus VIPER™ system, used with Micro Sensors. According to Shadow Robot’s engineering team, small sensor size, high update rates, and the lack of need for line-of-sight is what set Polhemus technology apart from the rest.

What is VIPER?

VIPER™ is the latest motion tracking system by Polhemus. It’s a high-speed, high-fidelity system, with update rates up to 960Hz, fast enough to track the quick hands and fingers of a high-fidelity robot. VIPER delivers latency as low as 1 millisecond, and tracks up to 16 sensors. 

Due to the propriety nature of Polhemus magnetic tracking technology, the challenges with line-of-sight occlusions were eliminated. Polhemus technology has the rare capability to track through gloves, walls, clothing, and people. 

The Polhemus Micro Sensors slip on and off easily, with optional Micro Mounts, making them the preferred choice for professionals doing hand and finger tracking. The sensors are easily embedded into hardware, clothing or other form factors, and are available with a standard, more rigid cable and a flexible, pliable cable, perfect for hand and finger tracking, or in this case, robot hand and finger tracking.

"You have world-class dexterity from the human-like, five-fingered, robot hand and you can track user fingertip positions and orientations with no line-of-sight required, using the conveniently small and mighty Polhemus sensors."                     
-Rich Walker, Managing Director, Shadow Robot

Image courtesy of Shadow Robot: The Shadow Dexterous Hand Series

The collaboration of Polhemus motion tracking technology and Shadow Robot’s Dexterous Hand was ground-breaking, paving the way for new, complex applications in robotics. According to Rich Walker, Managing Director of Shadow Robot, “The combination of the precision motion tracking of Polhemus sensors and the renowned Shadow Dexterous Hand from Shadow Robot truly revolutionizes remote working when used in our teleoperation system. The integration of the two leading technologies is a must-have for any researcher in robotics.“

About Shadow Robot

Shadow Robot applies robotics technology to solve real-world problems for people. They’re best known for designing and manufacturing state-of-the-art anthropomorphic robot hands, like the Shadow Dexterous Hand Series, the World’s Most Dexterous Humanoid Robot Hands. Specializing in custom robot solutions, Shadow Robot is experienced in design, development and production. Along with designing and fabricating their latest products, they help clients solve difficult problems with the most innovative robotic systems on the market. They lead with innovation, but stay guided by their ethics, keeping to their strict mantra of creating “robots for good” policy. Learn more about Shadow Robot. 

About Polhemus

Polhemus is the global leader in high-fidelity motion measurement. They have been helping customers break new ground with best-in-class 6DOF electromagnetic tracking and digitizing systems for over 50 years. Polhemus products are widely used in such areas as: medical applications, university research, robotics applications, including robotics surgery, training and simulation, computer-aided design, virtual and augmented reality, and more.