In Praise of Project Planning, Pilots, Points and Processing

Knowing where to place your Markers

Marker placement is a huge subject and can be tricky to grasp if you are a newcomer to Motion Capture. Even highly qualified and experienced biomechanists can struggle when presented with a new project and a blank sheet. If your mathematical background doesn’t include a detailed knowledge of Vector Algebra where do you start?

If you can find similar studies in the published literature you may be able to use a previously developed marker-set and modeling protocol. Many lower limb studies will be based on the so-called Helen Hayes method (though it is also known by many other names). This is often regarded as the gold standard for Gait Analysis, despite being from the 1980’s. It was perfect for the camera systems of the day, using the absolute minimum number of markers to save all the post processing time. It solves problems that 21st century systems no longer have. Though take care as almost all models now are ‘modified-Helen-Hayes’ and they vary in subtle ways.

If you can’t ‘stand on the shoulders of giants’ where do you begin? 

Let’s consider Markers, Virtual Markers and Points (ie coordinates in 3d space). Each segment that you want to track will need at least three, non-linear, points to give all six degrees of freedom, XYZ and 3 Rotations. An individual marker tells you a position; singularly it can’t give you an orientation.

These can be real markers or virtual ones, which are points calculated from marker data but offset in a rigorously defined way. For example if you want to know where a Knee Joint Centre (KJC) is, you can’t place a marker inside the body but if you can place two, carefully on the surface where the knee joint axis line passes through the skin it is possible to readily define the KJC, as a Virtual Marker, halfway between them. Motion Analysis’s highly regarded Cortex software has an easy to use graphical interface that presents this and even more complex Vector Algebra with beautiful simplicity.

Three markers for every segment can soon add up, but often a single, carefully defined point (real or virtual marker) can be shared. That KJC point, or the outside knee marker can be used for the thigh and shank segments.

After you have decided on a marker set that covers the segments that you need to know the angles between, plus all the other spatial–temporal parameters which Cortex will also calculate for you, you’ll be ready to get on with the fun part: the motion capture of all your subjects. Or can you?

You may need to revise your ideal marker set due to the reality of you systems camera count and the specific move you want to analyze. For example, if your laboratory has cameras permanently fixed high on the walls and you are studying push-ups, any markers on the front of the subject will be impossible to see. For the chest you could just place three or more markers on the subject’s back and remove the front markers. Or better still leave the front markers, add additional back markers and use predefined tools to recreate the ‘lost’ markers with virtual ones calculated from the relative positions of these extras. There are gap filling interpolation tools but they are making up data, whereas these ‘virtual joins’ are using genuine information.

It’s worth consider a Pilot Study

If this is all seeming a bit difficult to grasp, then we highly recommend a Pilot Study. Often the best way to find out what snags are going to catch you out is to get in the lab and try it. Set aside time to try a couple of subjects with different marker sets. Work through this data and find out where markers need adding, or which ones are not needed. It will also help you decide which parts of the myriad results are essential for your study.

Time and effort spent on a Pilot Study early on always saves you later down the line! It can help prevent hours of clean up and post processing, and most often it highlights a tiny tweak that could have prevented you answering the actual question you set out to study.

If you don’t have a lab yet but are thinking of investing in one then please contact Motion Analysis, we’ll be happy to discuss your experiment. We’ve helped set up thousands of labs around the world and will be happy to assist.

Important considerations when purchasing a motion capture system

If you’re still in the process of deciding on the motion capture system you need, we have put together a helpful checklist to keep in mind during your decision making process.

Cortex 10 Raises the Bar for Motion Capture Excellence

Motion Analysis has built its reputation over 40 years as a pioneer of innovative motion capture technology. Our powerful Cortex software platform has become the gold standard for biomechanical researchers, animators and movement scientists around the world. Today, we are proud to announce the release of Cortex 10 – a new version with some great new capabilities.

With each new iteration, we strive to push the boundaries of what’s possible in motion tracking and analysis. This release introduces several features that will streamline workflows, unlock new research potential, and elevate the precision of motion data like never before.

Integrated Glove Tracking

One of the most significant additions in Cortex 10 is the seamless integration of MANUS Meta glove technology. We have combined the robust, marker-based motion capture core of Cortex with MANUS’s high-fidelity finger animation data stream. This yields an unprecedented level of hand tracking fidelity from a single unified data channel for biomechanics and animation.

Automated Marker Identification

Setting up robust marker identification can be a tedious process. With Cortex 10, we’ve dramatically simplified this workflow using new automated tools. We provide four pre-built “golden” marker templates that can auto-scale to subjects in real-time. Additionally, a new marker generation script allows users to rapidly build custom marker sets from previous capture data.

Intelligent Batch Processing

The new batch processing options in Cortex 10 add a level of intelligence and customization that will optimize post-production pipelines. Users can now selectively process and export files based on the capture status and file type using a simple selection menu or custom scripts. This makes it easy to streamline exports for analysis while excluding any unwanted capture files.

Collaborative Marker Management

To foster better teamwork, we’ve made the central system objects folder used for storing marker definitions fully editable in Cortex 10. This allows multiple users to access a shared network location for storing and managing marker object variations across consecutive projects.

Simplified Multi-Markerset Handling

Another key addition is markerset-based capture trimming using new built-in scripts. This tool is critical when dealing with complex captures involving multiple markerset objects, which can convolute the data stream. With a simple script, users can trim out individual markersets for clean, focused analysis.

HD Video Integration

Last but not least, Cortex 10 adds integration with our new Rainbow camera line. These reference video cameras can record full HD at over 80FPS or 1.1Mpxls above 100FPS while precision synchronized too the motion capture data stream. This offers vastly improved video reference capabilities for analysis.

We have worked tirelessly to pack Cortex 10 with innovations that will help our users capture more precise movement data through streamlined workflows and enhanced processing power. This release is a major step forward that reinforces why Cortex remains the most trusted and capable motion capture software platform in the world.

Cortex 10 is now available to all Motion Analysis customers with current support contracts or warranties. We encourage you to upgrade today to take advantage of these powerful new features. As always, we welcome any feedback from our user community as we continue raising the bar for motion capture excellence.

Book a demo today

Introducing our new Reference Video Camera: The Rainbow

We’re proud to introduce Rainbow – our new line of HD video reference cameras designed to bring synchronized color video seamlessly into the Motion Analysis ecosystem.

An Integrated Reference Video Solution 

We developed the Rainbow cameras to integrate with our optical motion capture workflow. At its core, Rainbow leverages IEEE 1588 Precision Time Protocol (PTP) technology to eenable precise  synchronization between the HD video stream and data captured from from our Thunderbird motion cameras. They will also work with Kestrel and other camera ranges.

This tight sync integration, combined with Rainbow’s impressive specs like Full-HD resolution at over 80 fps, and full vibrant color imaging, allows users to incorporate multiple HD camera views with lens-mapped video and 3D workspaces overlays. The resulting outputs are highly compressed AVI video files compatible with virtually any third-party video editing, analysis or markerless tracking tool.

Simple, Flexible Setup 

Powerful integrated video is only half of what makes Rainbow a game-changer. We’ve also ensured that these cameras are easy to incorporate into your motion capture volume or studio setup.

Rainbow uses standard C-mount lenses, putting the industry’s full range of optics at your disposal for coverage flexibility. Power over Ethernet (PoE) allows for a single ethernet cable run to each camera with 150 feet of reach, or more. A typical set up will have 6 Rainbow cameras but 8 channels or more is possible with high end PC hardware.

Whether you’re looking to add context with static wide shots or dynamic tracking cameras, configuring multi-angle video reference  is easy.

Empowering intelligent data visualization

With Rainbow’s ability to provide synchronized, high-fidelity color video streams precisely aligned to optical motion capture data, we’re empowering our users to take their movement analysis capabilities to new heights. Sports scientists can cross-reference player biomechanics to multi-angle video for deeper insights. Biomechanists can have HD video with lens mapped fidelity for vector overlays.  Animators can have multiple reference viewpoints for their shot-log.

Rainbow HD video cameras are now available to our global customer base.

Contact us for more information

The biomechanist’s motion capture purchasing checklist

What is a motion capture system?

A motion capture system is a technology that records the movement and positioning of objects or individuals in three-dimensional space. It is widely used in fields such as biomechanics, movement science, and animation to accurately analyze and study human or object motion.

How can a motion capture system enhance the work of a biomechanist?

Motion capture systems provide biomechanists and movement scientists with valuable data and insights that can enhance research, clinical assessments, and the development of interventions. By capturing precise, three-dimensional movement data, researchers can gain a deeper understanding of factors such as joint kinematics, muscle activation patterns, and overall movement efficiency.

What does a motion capture system consist of?

A typical motion capture system includes the following key components:

Important considerations when purchasing a motion capture system

When evaluating and purchasing a motion capture system, consider the following factors:

Conclusion

Selecting the right motion capture system is crucial for biomechanists and movement scientists to effectively conduct research, assess clinical interventions, and gain valuable insights. By considering the key factors outlined in this checklist, you can make an informed decision that aligns with your specific needs and enhances the quality and impact of your work.

Motion Analysis Corporation Unveils Cortex 9.5 Software Upgrade

November 8 2023, California – Motion Analysis Corporation is excited to announce the highly-anticipated release of Cortex 9.5, the latest edition of its cutting-edge motion capture software. This update is now available for download and is accessible to all customers with active warranties or current software maintenance contracts.

Cortex 9.5 introduces a range of exceptional features and improvements that elevate the motion capture experience to new heights, providing users with greater flexibility, efficiency, and accuracy. Here are the key highlights of this remarkable update:

Quick Files Capture Status: Cortex 9.5 introduces Quick Files Capture Status indicators, simplifying the assessment of dataset status. Users can easily classify captures as “Unedited,” “In Progress,” or “Complete.” Customization options are also available, allowing users to create their own status names and icons, providing a user-friendly experience.

Kestrel Plus Cameras: With Cortex 9.5, Motion Analysis Corporation introduces the Kestrel Plus camera line, featuring the Kestrel Plus 3, Kestrel Plus 22, and Kestrel Plus 42. These new cameras seamlessly integrate with Cortex 9, expanding your capture capabilities and delivering high-quality results.

Trim Capture Modifications: Cortex 9.5 enhances the Trim Capture feature, enabling users to modify names, generate captures on a per-markerset basis, and add timecode support. This streamlined process facilitates the extraction of relevant data from capture files and offers improved post-processing options.

Workflow Improvements: Cortex 9.5 enhances the Workflow feature, making task execution even more efficient. Users can now utilize a search tool and a workflow repository, enabling easy access and management of workflows, optimizing productivity.

Live Detailed Hand Identification: Advanced hand tracking techniques have been integrated into Cortex 9.5, reducing marker swapping during live collection and post-processing of intricate finger movements. Users can contact the support team for a sample markerset to enable this feature.

Automatic Wand Identification for Reference Video Overlay Calibration: In a significant time-saving move, Cortex 9.5 automates the marker selection process for reference video overlay calibration, eliminating manual marker selection and potential user errors. This feature can be applied in both Live Mode and Post Process.

Bertec Digital Integration: Cortex 9.5 now offers support for Bertec AM6800 digital amplifiers, simplifying setup and reducing the number of required components, thus enhancing the overall user experience.

National Instruments New Device Compatibility: Cortex 9.5 continues its support for National Instruments A/D board data collection and expands compatibility to their next generation of DAQs, maintaining flexibility and ensuring compatibility with previously supported devices.

Additional Updates and Features: Several additional updates and features, such as the renaming of the Post Process X panel to Tracks, improved contrast in Dark Mode, and an increased marker slot limit, are included in this feature-rich update.

Cortex 9.5 marks a significant milestone in the field of motion capture, empowering users with advanced tools, enhanced workflows, and improved performance.

To learn more about Cortex 9.5 and take advantage of these exciting new features, download the full release notes here, or contact our sales and support teams for further information and assistance.

Motion Analysis Corporation continues to lead the way in motion capture technology, and Cortex 9.5 is a testament to our commitment to delivering innovative solutions that meet the evolving needs of our customers.

About Motion Analysis Corporation

Motion Analysis Corporation is a leading provider of motion capture technology solutions for various industries, including entertainment, sports, healthcare, and research. With a focus on innovation and customer satisfaction, Motion Analysis Corporation strives to make motion capture more accessible and versatile.

Five (more) things you might not know about Cortex motion capture software

In July 2021, we debuted Cortex 9, which enabled users across a wide range of industries – from researchers and scientists to engineers, biomechanics professionals and creatives – to use motion capture more efficiently and effectively. 

And now, we’re taking things up a notch with Cortex 9.2. The latest version of our Cortex software, Cortex 9.2 is all about expanding digital integrations; particularly the Ultium EMG and IMU systems from Noraxon. Before Cortex 9.2, users would have needed extra components – including additional hardware, extra cables and a wire for each channel – to collect data from a Noraxon system in Cortex. This could get quite messy and add complexity to a setup. Now, the setup simply requires a USB cable from the Noraxon base unit into the PC.

In addition to this, we have also expanded the types of Delsys sensors that can be used. The latest version of Cortex is compatible with two more sensor types, doubling what was previously available. And we’ve added additional compatibility with reference video cameras and made improvements to digital force plate integrations for TecGihan and Kistler. The latest version of Cortex also includes several bug fixes, as is standard with any new release. 

A little while back, we showcased several Cortex features users might not know about. With the recent release of Cortex 9.2, we’re adding to this list. Take a look.

Capture Inspector 

Captures can consist of many file types covering tracks, raw camera data, analogue, marker sets and so much more. In addition to this, when users are analyzing their capture, they are often copying data from one computer to another. All of this increases the likelihood that you could ‘lose’ certain files. With the Capture Inspector assistant panel you can easily identify when data gets lost or mixed up and clean up and rename files so that it’s easier to find them down the line. 

Golden Templates

If you’re using the same marker set for every subject, you can keep adding information – things like height, size, shape – and the Golden Template will keep learning. This means that rather than having to manually identify each and every subject, Cortex 9.2 will automatically add the subject’s linkage lengths and range from a Golden Template. So users no longer have to name each marker individually, making it possible to automatically label a new subject when they enter. 

Moving Origins

One of our exciting new post process analyzing tools allows you to make adjustments to characters that might not quite be in the volume or at the angle you want them to be in. With Moving Origins, you can simply slide the character into the correct space, adjusting the origin of a live piece of equipment.

Normalization

When you’re comparing person A to person B or you’re looking at someone wearing shoes versus someone without shoes on, you need to have a sense of what is ‘normal’ and use this as your baseline. This entails plotting a movement through a cycle from 0 – 100. With Cortex 9.2, you can normalize the amount of time it takes to complete a movement so that it’s easier to compare one cycle of data to another. Once you’ve worked with 20 or 30 subjects you can get a sense of an average and then identify any differences or deviations from the ‘normal’.

Workflows

With the Workflows panel, introduced with Cortex 9.0, users can quickly automate repetitive tasks. This saves time and delivers greater consistency between users. Workflows can be set up to include any number of functions in Live Mode or Post Process mode and are ideal for users who don’t have scripting or coding experience. Once a workflow is created, it can then be saved and applied to different capture sessions and by different users to maintain a consistent protocol.

And if you’re in need of a little help, the full Cortex 9.2 manual and QuickStart guide can be launched from the HELP tab. And when using the software, if you click the ‘?’ on the page, a context sensitive Panel Help bar will appear. 

Want to see one of the many new Cortex 9.2 motion capture software features in action? Check out this video of a workflow designed to get you ready for subject collection in just a few clicks.

Why Intel partners with Motion Analysis to bring technology to Olympic athletes

THE CUSTOMER

The Intel Olympic Technology Group (OTG) is a division of Intel focused on bringing cutting-edge technology to Olympic athletes and helping them to better prepare for the Olympic Games.  

THE PROBLEM

The Intel OTG wanted to create a smart coaching application using computer vision pose estimation models. These models use key point locations on the body, like joints, to calculate biomechanical attributes relevant to athletes, such as velocity, acceleration, and posture etc.

THE SOLUTION

Motion capture was first used in biomechanics in the late 1970s to analyze a subject’s gait. But a lot has changed since then. Today, this technology is being used across the increasingly data-driven sports industry. 

The information generated using motion capture software empowers coaches to identify issues that may be preventing a player from improving their performance. This technology can also be used to prevent injuries. When physiotherapists use motion capture software to analyze the kinematics of a particular movement, it is feasible to identify any range of motion (ROM) issues and determine if these are linked to pain or injury in the athlete. When it comes to movement analysis, the accuracy of data is key. The precise data collection and instant translation of this data makes it viable for coaches and physiotherapists to identify areas where re-injury might occur, determine an appropriate recovery time and provide evidence-based recommendations for rehabilitation. 3D motion capture software can also be used to track the movements of an entire team. This data can be used by coaches to strategize better because it is possible to track a range of player performance factors – like accelerations or decelerations.

Benjamin Hansen, Product Engineering Lead in AI & Sports Technology for Intel OTG, has been using motion capture to do just this. Describing himself “a lifetime customer of Motion Analysis”, he has utilized Motion Analysis systems to provide athlete testing services to elite athletes and professional baseball teams. And now, he’s using Cortex to validate and benchmark the smart coaching application described above.

Cortex is Motion Analysis’ most powerful motion capture software that completely manages motion capture and measurement for all applications from biomechanics, broadcasting, and engineering to sports performance, game production, and film.

One of the projects the OTG worked on using Cortex was 3D Athlete Tracking (3DAT). Intel’s motion tracking platform, 3DAT, creates scalable technology that advances the understanding of human health and performance. Crucially, it relies on a Motion Analysis system, which includes Kestrel cameras and Cortex software, to benchmark data accuracy in order to inform the necessary algorithms. Developed over four years for athletes competing at the Tokyo & Beijing Olympics, 3DAT is now being commercialized as a camera agnostic motion capture software development kit (SDK) that developers can use to create biomechanics solutions for the sports, health, and fitness industries.
 
Want to find out more about Intel’s journey with Motion Analysis? Download the full case study, here, to learn more.