Frequently Asked Questions

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  1. About the Device
  2. Wearability
  3. Safety Concerns
  4. Connections
  5. Collecting Input
  6. Manipulating Output
  7. Development
  8. Maintenance and Storage

About the Device

QUESTION: What is the battery life of the device ?

ANSWER: When fully charged, the device will be able to operate for 1 full hour before it's battery depletes.

QUESTION: How long does it take for the device to reach a full charge ?

ANSWER: When charging through a USB connection, the device takes around 1.5 hours to complete a full charge.

QUESTION: Where can I obtain my Developer ID ?

ANSWER: At the moment, Developer IDs are provided only to our Backers on Kickstarter.


QUESTION: Where on my forearm should I wear the device ?

ANSWER: With your palm facing up, locate on your forearm, the midpoint between your wrist and your elbow. The UnlimitedHand should be set so that it's center (Power Switch location) covers that point on your forearm.

QUESTION: The circumference of my arm is too large/small for the device, what should I do ?

ANSWER: For those who have relatively lean forearms, try wearing the device closer to the elbow side of your forearm. If the wear remains loose, we will provide you with a S-sized silicon pad as a replacement. For those who have relatively thick forearms, try wearing the device closer to the wrist side of your forearm. If the wear remains tight, we will provide you with a L-sized silicon pad as a replacement. Contact us at for replacements.

QUESTION: How tight should the device be worn around my forearm?

ANSWER: It should not be loose to a point that the device shifts in position when the arm is moved. It should not be tight to a point that the intervenes with regular circulation of the arm.

QUESTION: Does it matter which arm I wear the device on ?

ANSWER: No, the device is compatible with both left and right hands.

QUESTION: Do I need to shave my arm for optimum performance ?

ANSWER: No, body hair will not make a difference to both input and output functionalities of the device.

Safety Concerns

QUESTION: Should I let my children try on the device ?

ANSWER: It is safe for children to try on the device, however make sure the child acknowledges what the device is capable of in order to prevent accidents caused due to unsupervised use. For this reason it is best to keep the device away from small babies or children who cannot manage to express themselves with words.

QUESTION: My arm feels fatigued after a development session, is this normal ?

ANSWER: Temporary fatigue may be experienced due to consistent working of the muscles by the device. Similar to a round of work out, your muscles require a short recovery period. Avoid using the device until fatigue disperses. Please consult a Doctor if fatigue persists.

QUESTION: Can the device still deliver electrical stimulus after it is turned off ?

ANSWER: The device will not be able to deliver any form of stimulation while it is turned off.


QUESTION: What is the maximum Bluetooth transmission range of the device ?

ANSWER: In an ideal environment, the device will have a 10m (33ft) range. With obstructions counted in 6 - 8m (20 - 26ft) would be the approximated range.

QUESTION: Can my device automatically pair itself with my game ?

ANSWER: Once the device is paired with your computer, the device will be recognized as long as you are in the range of the computer's Bluetooth transmission range. You may add an handshake sequence into your game's loading operations to make confirmations.

QUESTION: Why can't I establish a Bluetooth Connection ?

ANSWER: Confirm that your device is already paired with the computer. For details, follow the instructions in this tutorial. Be sure that you are within the device's transmission range of 6 - 10m, and that the device is not already connected to an active USB port.

QUESTION: Is it possible to program the device through a USB connection rather than Bluetooth ?

ANSWER: Certainly, for developers who dislike being interrupted by broken connections, USB development is the way to go. Be reminded to confirm that the correct port is selected.

QUESTION: Is it possible to separate the main case and the silicon pad while developing?

ANSWER: No, it is not recommended to do so. While not worn around the arm, please make use of the Safekeeping Tray provided as part of the package to cushion the bared components at the back side of the device.

QUESTION: Is it possible to link UnlimitedHand with external hardware ?

ANSWER: Yes, through the ICSP port built into the device, you can extend the UnlimitedHand's reach to other appliances as well. Unhook the silicon pad from the main case to separate the two components, lift the main case and you will find a small rectangular opening that reveals 6-pin ICSP headers.

QUESTION: Is it possible to synchronize stimulations for dual UnlimitedHands ?

ANSWER: Yes, with both devices serially connected to your computer, you may read in values or deliver stimulations to both devices separately or simultaneously. The conditions can be programmed under Arduino IDE or C# scripts for Unity.

QUESTION: The device is not recognizable by my PC and appears as unknown device.

ANSWER: It may be a problem with the USB connection, please try using another cable (with data transfer).

Collecting Input

QUESTION: What movements do each of the Photo-Reflector values represent ?

ANSWER: By monitoring data coming from specific Photo-Reflector combinations, you may track 3 main types of movements performed by the hand. Access section 1.0 from this page to learn more.

QUESTION: Is it possible to narrow values down to track movement of individual fingers ?

ANSWER: The movement that each Photo-Reflector value covers may vary according to the build of the user's forearm. For this reason we cannot assure direct value-movement correspondence.

QUESTION: Will there be gesture events available for developers ?

ANSWER: Yes, a Sensor Calibration Kit will be released in August 2016 to help users get started with their projects that require gesture recognition.

Manipulating Output

QUESTION: Will stimulation weaken as I move further away from the computer ?

ANSWER: No, as long as a working Serial Connection is established, distance makes no difference to the strength of electric stimulation.

QUESTION: How can I lengthen or shorten the sustain of Electric Stimulus ?

ANSWER: Yes, you can adjust it by changing the number of total rounds of electrical stimulus delivered. Please refer to this tutorial for more details.

QUESTION: Can I adjust the strength of stimulation delivered for individual electrodes ?

ANSWER: No, at the moment UnlimitedHand only supports the tuning of general stimulation strength that will affects all electrodes at once.

QUESTION: Stimulus can be felt on my arm but not my fingers, how do I fix this ?

ANSWER: Make sure that you are wearing the device in the recommended position. Please refer to this question for details.

QUESTION: Can I create my own preset stimulation patterns ?

ANSWER: Yes, you will be able to deliver two or more electrical stimulus patterns at once to experiment with compound stimulations that suit your body/cause.


QUESTION: Where do I get the Arduino Library ?

ANSWER: The download for the Library can be found at this link

QUESTION: Where do I get the Processing Library ?

ANSWER: The download for the Library can be found at this link

QUESTION: Where do I get the Unity Plug-in ?

ANSWER: The download for the Plugin can be found at this link

QUESTION: Are OpenFrameworks addons in development ?

ANSWER: An official add-on is not being developed at this moment.

QUESTION: I cant seem to upload sketches to Arduino

ANSWER: Please follow this link for a list of solutions that might be related to your issue

Maintenance and Storage

QUESTION: How should I clean the silicon pad of my device ?

ANSWER: Never soak the device into water or clean it directly with water. Use a dry towel to brush and rub off dirt and dust. Persisting spots or stains, try using a towel slightly dampened with detergent.

QUESTION: Can I get replacements for the blue gel pads ?

ANSWER: Yes you can, please access our home page for a list of purchasable accessories. There will come a day when your gel pads loose their adhesiveness and cease to stick to your skin. At this time, please consider replacing your gel pads to allow for optimum performance of the device.

Other Introductions

How to use at first with Arduino / Install the UnlimitedHand Library for Arduino / Upload the Arduino sketch to the UnlimitedHand / Introduction Page: How to connect via Bluetooth / Strap the UnlimitedHand on your foream / Submit your topic on the UnlimitedHand forum