A Complete Guide to Bionic Arms & Hands

Bionic Arms Hero

Everything you need to know about bionic arms and hands, with descriptions of all the current devices, technologies, and the latest research. Continuously updated, this page is intended as your one-stop repository for information on upper-limb bionics.

What’s On This Page?

What is a Bionic Arm?

A bionic arm is an electromechanical device that attaches to the human body and replicates the functionality of a natural arm/hand.

It always consists of a bionic hand or partial hand and, depending on the level of amputation, may also include a powered wrist, elbow, and/or shoulder.

For example, here are the three configurations available for the Luke Arm System from Mobius Bionics:

Luke Arm System Configuration Options

Note, this particular line of devices always includes a powered wrist but this is optional or not available for other devices. Also, in some use-cases, the hand may be replaced with a powered hook or clamp.

How Bionic Hands Function

This section is intended to teach you the limits of bionic hand dexterity. The best way to do this is to briefly describe the mechanical design of the fingers and work backward.

The core mechanical function of a human finger is to open and close. This is replicated in a bionic finger using a design like this:

Finger Design for Bionic Arms

Source: https://doi.org/10.1016/j.ohx.2020.e00100

A battery-powered motor drives a gearing system to move the main MCP joint, which then moves the second and third joints via a bar linkage system. Note, there are many variations of this, such as using pulley systems to simulate tendons instead of bar linkage systems.

The key feature in this type of design is that there is typically only one independent joint: the MCP joint (main knuckle). The other two joints automatically follow that joint’s lead, producing the following fixed pattern of motion:

Bionic Finger Pattern of Motion

Source: https://doi.org/10.1016/j.ohx.2020.e00100

By comparison, natural fingers can move the middle or PIP joint independently and the DIP joint quasi-independently. Additionally, natural fingers can spread out and twist and turn in a myriad of combinations.

The movement of a natural thumb is even more challenging to duplicate. In addition to opening and closing, it can rotate down and slightly outward to touch the entire underside of any finger and even parts of the palm. This allows natural hands to grasp objects of any shape.

Here is a diagram of a bionic thumb from the early work on one of the more recent entries into the bionic hand market, the Psyonic Ability Hand.

Thumb Designs for Bionic Arms

Despite its mechanical complexity, this type of thumb still has many limitations. Yes, it can position itself to become an opposable force for many grips but it lacks the exceptional dexterity of a natural thumb.

This exemplifies one of the main points of this section: bionic hands are impressive feats of engineering but they are much simpler than natural hands. In one respect, this hardly matters because they can still perform a wide variety of tasks, as demonstrated in this video:

However, do not expect them to match the dexterity of natural hands. A better way to assess a bionic hand is its usefulness, which is determined mostly by its user control system.

User Control Systems

When you move a natural limb, your brain sends nerve signals to the muscles, which in turn move the limb.

When a limb is amputated, the brain still sends these signals even though some of the muscles are no longer there to receive them.

The general concept behind bionic user control systems is to intercept the brain’s signals and convert them into commands for the bionic device.

There are multiple ways to do this for bionic arms & hands. For a quick overview of control system options, see bionic hand control systems. For details on each option, click the relevant link below:

Whatever you do, do not neglect this subject. User satisfaction levels depend almost entirely on selecting the right control system.

Current Below-the-Elbow Bionic Arms & Hands

Deus Ex - Hero Arm Covers

Available Models

The following is a list of the models for below-the-elbow bionic arms & hands either already on the market or soon to be (presented alphabetically). Each links to its own page for more specific details:

All of these hands offer myoelectric direct control systems at a minimum. Those sold as components (i.e. where the hand is designed to be a component of a bigger system) can also be used with pattern recognition control systems. We do not know of any commercial bionic hands currently being used in combination with a true neural interface, though there is nothing that prevents a component hand from doing so.

Affordability

Of the bionic hands currently on the market, the most affordable are the TrueLimb from Unlimited Tomorrow, the Hero Arm from Open Bionics, and the Zeus Hand from Aether Biomedical. In their simplest configuration (least complicated residual limb), the final price for these three devices can range from $8,000 to $15,000 US, including prosthetist fees, where applicable.

By comparison, the most expensive hands can cost more than $60,000 US.

For more information, see our Bionic Hand Price List.

Current Partial Hand or Finger Options

Partial Hand Prosthesis Options

Nearly 2/3 of upper-limb amputations involve finger or partial hand loss. This equates to millions of people around the world who are missing fingers, parts of fingers, or a part of their palm.

Both Ossur and Vincent Systems have created excellent bionic partial-hand prostheses but these are not well-suited for heavy loads or challenging environments. They’re also quite expensive. To address these deficiencies, our list of articles on partial-hand devices includes the best non-bionic (i.e. strictly mechanical) options:

In keeping with our goal of helping you stay informed, we have also created a Current Partial Hand Prosthesis Options summary page. We will constantly update this page so that you can use it as a convenient place to stay informed about all the latest partial hand devices.

Current Above-the-Elbow Bionic Arms

In general, the further up the arm an amputation occurs, the more complex the requirements for a bionic prosthesis. This is due in part to the need for additional moving joints. But weight and power consumption also increase, as does the requirement for a stronger attachment to the residual limb or body.

Solving these problems required a bigger budget and more technical collaboration.

Enter the Defense Advanced Research Projects Agency (DARPA). In 2006, the agency launched its Revolutionizing Prosthetics program. The goal of this program was to develop a bionic arm to dramatically improve the quality of life for upper-limb amputees. They wanted an arm capable of mimicking the natural arm and hand movements for any level of amputation.

Two advanced bionic arms resulted from this program.

The LUKE Arm

The LUKE Arm was developed for DARPA by DEKA Research and Development Corporation.

In 2014, the FDA approved the arm for commercial use:

As you can see in the video, the arm clearly fulfills its original goal. It can indeed mimic most natural arm and hand movements. In the preceding video, the wearer uses foot controls like joysticks to manipulate the arm.

However, myoelectric direct control and pattern recognition systems can be used here, too.

We have not yet been able to find any instances in which a patient is using the Luke Arm in combination with a true neural interface, as most of this work is still occurring in the lab.

Modular Prosthetic Limb (MPL)

The Modular Prosthetic Limb (MPL) was developed for DARPA by Johns Hopkins University (JHU). This is a more complex hand/arm system designed to “test direct neural control of a prosthesis”.

It has since made its way out of the lab and into home trials.

As the video demonstrates, the ability to manipulate this arm via thought is quite sophisticated. But it still isn’t as good as a natural arm/hand.

Ottobock’s DynamicArm

Ottobock has offered the DynamicArm for sale since late 2009. Although its technical origins are not entirely clear, it appears to be an above-the-elbow version of the myoelectric arms that have become so popular for below-the-elbow amputees. Put another way, it is a highly effective bionic arm for the above-the-elbow amputees but it does not have the sophistication of either the LUKE arm or the MPL.

Here it is in action:

Affordability

The big problem with above-the-elbow bionic arms is cost. The LUKE Arm costs as much as $100,000 US. The cost for the MPL, should it get to market, will likely be similar. Even the DynamicArm, commercially available for over a decade, is still around $60,000 US.

Unfortunately, this price tag exceeds the budget of most amputees. However, we should not be discouraged by this. It takes a while for new technologies to trickle down into the broader market. And then it takes even longer (i.e. the effect of market forces) to significantly reduce costs. We just have to do what we can to accelerate these processes.

In the interest of accuracy, both the LUKE Arm and the MPL are not strictly above-the-elbow prostheses. Their modular design allows them to be used for all levels of upper-limb amputation.

Latest Research Articles for Bionic Arms & Hands

Bionic Arm & Hand Control Systems

When looking at a bionic arm, many people believe that the hand and the arm joints are the primary technology components. This is not true. It is the user control system that holds the key to restoring near-natural capabilities.

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Sensory Feedback for Bionic Hands

The ultimate goal of bionic hands is to replicate natural abilities. For this to happen, bionic hands will need to provide advanced sensory feedback. This is not only a matter of reconnecting users to their surroundings through touch. It is…

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Bionic Feats for Bionic Arms & Hands

Bionic Feats: Food Preparation

Preparing food is a daily activity that is essential for personal independence. In these videos, we show you various bionic hands hard at work in the kitchen.

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Bionic Feats: Heavy-Duty Hand Work

Bionic hand technology is improving all the time, with a lot of emphasis on better control systems, more sensory feedback, and faster response times. But these devices still tend to be relatively fragile. In these videos, we show you a…

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Bionic Feats: Tying Shoelaces

Tying shoelaces is a real challenge for bionic hands because it requires significant dexterity. For a hand to truly play its part in this task, it should have good hand speed and the ability to switch grips with ease.

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Bionic Feats: Let There Be Music

Our love of music is universal. For some, it’s so powerful that they can’t resist the desire to make a bit of music on their own. Here are four amputees fulfilling that desire.

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Real Stories for Bionic Arms & Hands

Seeking User Feedback on Bionic Limbs

At BionicsForEveryone.com, we are very clear about where our loyalties lie when it comes to bionic limbs, and that is with end-users. We don’t have anything negative to say about bionic companies. On the contrary, we have great respect for…

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The Revolution in Prosthetic Aesthetics

There is something transformative happening in the prosthetics industry — a long-overdue awakening among product designers, those with limb differences, and the general public that is helping us take a big step toward a more inclusive society.

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Master Innovators in Bionic Limbs

The innovators featured in this post are all accomplished scientists, engineers, and/or inventors. They have all made significant contributions to the advancement of bionic limbs. But what makes them truly special is their passion to improve the lives of those…

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Bionic arms can attach directly to the humerus (upper arm bone) or radius and ulna (forearm bones) through Osseointegration. This improves range of motion, strength, stability, and also adds a rudimentary sense of touch (through vibration). For more information, see Osseointegration for Bionic Limbs.

For a comprehensive description of all current lower-limb technologies, devices, and research, see our complete guide.