28th October 2026
The preset grips on Hero PRO and Hero RGD are designed around the way most people use their hands every day. Sometimes a patient wants the hand to move in a very particular way: for a tool they use at work, a hobby they love, or simply the way they like to hold something.
Custom Grips let you and your patient tailor a grip to that task or preference. You set where each finger goes and when it gets there, adjust how firmly the hand holds, preview the grip in 3D and test it on the patient’s hand in the same session.
This guide covers when a Custom Grip is worth building, how to approach one and how to refine it with your patient.
The preset grips cover most of what patients need day to day. Custom Grips are there for the exceptions.
“The grips in the existing pool cover the large majority of what most people need. But there are always exceptions, and people may want or need to do something very specific for their job. This allows users to do those more specific, one-off grips now.”
Daniel Green, CPO, Open BionicsOur CPOs consider a Custom Grip when a patient:
“A clinician would reach for a Custom Grip when the patient wants to combine multiple grips into one smooth motion, or if they want to individually control digits for specific tasks.”
Ian Reyes, CPO, Open BionicsHolding a throttle and pulling it toward the body while pressing a button with the thumb.
A firmer, more stable hold around different handle shapes and sizes, from a small wrench to a large kitchen knife.
A hold built around a specialized tool the patient uses for a hobby.
A hand shape built around holding a hand of cards.
Fun, expressive gestures shaped exactly the way the patient wants them.
Tilly built a grip that holds the pen between two fingers, just the way she wanted. Watch her build it below.
“One grip that could use finesse is something where the full open position is different while it’s closing and while it’s fully closed. There’s one patient I spoke with who needed to hold on to the throttle to pull towards the body while also using the thumb to press the button. This is a unique maneuver, and the Custom Grip allows the user to better control how the grip will act.”
Ian Reyes, CPO, Open BionicsCustom Grips add to good fitting and training. They don’t replace them. If socket fit, suspension or control is the real issue, deal with that first.
You can fine-tune one of the patient’s preloaded grips or build a new grip from nothing.
Our large variety of preprogrammed grips are designed to match standard anatomical grips, but there are endless possibilities.
Isabel Gonzalez, CPO, Open BionicsA Custom Grip is built from keyframes. For each step of the grip, you set where each finger moves and when it gets there.
Timing matters as much as position. The order the fingers close in can decide whether an object settles into the hand or gets pushed away. For example, you might bring the thumb into position first and then close the fingers around a handle.
A practical way in: set the start and end positions first, then add keyframes along the path of movement in between. Also check how the hand opens, not just how it closes. Some tasks need a different open position while the hand is closing than when it’s fully closed.
“I’d approach it by determining my start and end positions, and adding keyframes from there along the path of movement.”
Isabel Gonzalez, CPO, Open BionicsFor a tool, start with the hand in an open position. Then, to set the final position, place the real tool in the hand in the alignment you want. Work through the thumb, index, middle, ring and pinky fingers until the hand has a firm, stable hold on the tool.
“When you go to set that final position, I would place the tool in the hand in the correct alignment that you’re looking for. Being able to move the thumb in the correct orientation, the index finger, the middle finger, and then the ring and pinky fingers. You can really configure how to get it around the object that you would be looking to use.”
Jonah Rhymer, CPO, Open BionicsYou can adjust how firmly the hand holds an object. A grip for a paper cup or a pen needs a lighter hold than a grip for a tool handle.
Test grip strength with the real object, not a substitute. Weight, surface and shape all affect how secure a grip feels.
Preview the grip in 3D in the app to check finger positions and sequence before the hand moves. Then run it on the patient’s Hero PRO or Hero RGD and keep adjusting.
This quick loop of preview, test and adjust is what makes Custom Grips practical in a clinic session. You can watch the patient use the grip with the real object and make changes while they’re still in the room.
Once a grip is finished, your patient can share it with another Hero PRO or Hero RGD user, such as a friend, using a QR code.
The patient knows the task best, so build the grip with them. A simple session flow:
That handover matters. A patient who can build their own grips can keep adapting the hand to new tasks between visits.
“I would approach it by showing where to add the Custom Grips, showing them how to make one, and then having them add a Custom Grip themselves.”
Ian Reyes, CPO, Open Bionics[Our standard grips] are going to cover the majority of what people would like to do. The customization just puts a little bit more in the control of the patient.
Jonah Rhymer, CPO, Open BionicsHave an upper-limb evaluation coming up? Connect with an Open Bionics CPO for a demo, trial kit, or support with your case.
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