The Ottobock AxonHook is a strong, durable, and highly responsive terminal device for upper-limb bionic solutions. It is also surprisingly nimble.
What’s On This Page?
- A Quick Look at the AxonHook
- Grip Patterns & Control System
- Proportional Speed Control
- Sensory Feedback
- Wrist Design
- Lift Capacity & Grip Strength
- Water and Dust Resistance
- Glove Options
- User Software
- Suitability for Above-the-Elbow Solutions
- Clinical Insights
- User Feedback Survey & Results
- Considerations Before Buying An AxonHook
- Related Information
A Quick Look at the AxonHook
The following video shows the AxonHook in an industrial work setting:
The need for a strong and durable device in this type of environment is obvious, especially since multi-articulating hands (i.e. bionic hands with four movable fingers and a movable thumb) are notoriously fragile. But the AxonHook also has other advantages in this setting:
- Simplicity. The AxonHook has only one function — to open and close one of its hooks (the other hook is stationary). Multi-articulating hands offer multiple grip patterns. This may sound like an advantage but it requires the user to select the correct grip pattern before grasping an object, which can be cumbersome.
- Speed. Most multi-articulating hands are a bit slow to respond to user commands. Thanks in large part to its simplicity, the AxonHook can respond quickly.
- Visibility. The AxonHook’s minimalistic design makes it easy for the user to see the object he is trying to grasp and the placement of the hooks on that object. A bulkier, multi-articulating hand might obstruct the user’s view.
These three attributes mean that users don’t have to think about how they’re using the AxonHook — they just use it.
AxonHook Key Features
Grip Patterns & Control System
With only one grip pattern, the AxonHook does not need a complex control system. However, as part of Ottobock’s AxonBus System, it has one of the most capable control systems on the market.
This allows the AxonHook to participate in a surprising variety of tasks in a highly reliable manner, as shown in this series of short videos:
This is evidence of a well-designed device but there are circumstances where the AxonHook is not suitable. For example, where the user has to interact with a keyboard or touch panel.
Proportional Speed Control
When using myoelectric control, the AxonHook offers proportional speed control based on the strength of the user’s muscle signal. The device can close in as little as 3/4 of a second or as long as 10 seconds. The ability to close slowly and to stop precisely when needed allows for a gentler grasp of fragile objects.
The AxonHook does not provide any sensory feedback.
The AxonHook comes with a flexible wrist called the AxonWrist. This flexibility makes it easier to properly position the hooks while reducing the need for compensatory elbow and shoulder movements. Note that while this wrist does offer a quick disconnect capability, it is not the industry-standard version. Rather, it is the AxonBus System version, which allows uses to quickly switch between the AxonHook and the Michelangelo Hand but no others.
Active rotation can also be added, further improving the wrist’s adaptability.
Lift Capacity & Grip Strength
We have not been able to find any information on the AxonHook’s maximum lift capacity.
We do know that it has a maximum grip strength of 110 Newtons, which is quite high. By comparison, its multi-articulating cousin — the Michelangelo Hand — has a grip strength of 70 Newtons.
Having said that, grip force tends to be measured in different ways by different companies, so comparisons between the grip strengths of competing devices may not be reliable.
With only one moving hook, rigid at that, common sense suggests that the AxonHook should be considerably more durable than its multi-articulating counterparts.
However, we rely mostly on the results of our User Satisfaction Survey for an objective assessment of a bionic device’s durability. And because this article and the associated survey are new, it will likely be a few months before we have sufficient participants to publish results.
Water and Dust Resistance
The hooks of the AxonHook are splash-proof, but, otherwise, the device has an IP33 rating, meaning it is not waterproof or dustproof.
There are no glove options for the AxonHook.
We are not clear on the exact model of the battery used to power the AxonHook. We know that it is part of an integrated battery system called AxonEnergy Integral, and that this system should provide sufficient power to operate the AxonHook for a full day.
We also know that fully recharging the battery when completely drained requires around 3.5 hours.
We do not know the expected service life for the battery.
The AxonHook is controlled by the AxonBus System. This system does provide setup and configuration software (AxonSoft) for clinicians but not for end-users.
Suitability for Above-the-Elbow Solutions
The AxonHook can participate in above-the-elbow bionic solutions as long as the other components are also members of the Axon family. For elbows, this includes the Ottobock ErgoArm Hybrid Plus and the ErgoArm Electronic Plus.
Based on our information, the AxonHook should sell for between $15,000 to $25,000 US for a typical setup, including all socket and prosthetist fees.
For a complete list of prices for upper-limb ETDs, please see our ETD price list.
The AxonHook offers a 2-year standard warranty against defects in materials or workmanship under normal use.
We are not certain if this includes a service inspection at 12 months or whether this inspection is a condition of the warranty. We will submit this question to Ottobock and update this section when we receive a reply.
The following comments are from clinicians with extensive experience with the AxonHook:
User Feedback Survey & Results
Are you currently using an AxonHook or have you used it in the past?
If so, why not help others by sharing your experiences in this quick survey:
We do not yet have a sufficient number of survey participants to publish fair and accurate results for the AxonHook.
As soon as we do, we’ll update this section.
Considerations Before Buying an AxonHook
The AxonHook is the ideal complement to its AxonBus System counterpart — the Michelangelo Hand. The ability to switch between these two devices should address the vast majority of tasks and working environments with two exceptions. One exception is an environment that is consistently wet or dirty. Another is a task like operating a chainsaw, which requires a more secure gripping mechanism, a stronger grip force, and an even more rugged design.
The AxonHook can also be used as a primary device entirely on its own. The drawback to this approach is that it is not suitable for certain tasks such as operating a mouse or keyboard.
Otherwise, we are reserving judgment on the AxonHook until we hear back from end-users through our User Satisfaction Survey.
For a list of competitor devices, see all upper-limb ETDs.
For a comprehensive description of all current upper-limb technologies, devices, and research, see our complete guide.
Click here for more information on Ottobock Upper-Limb Prosthetics.