The ergonomic design of Glove80
Stephen Cheng from MoErgo describes the ergonomics of his Glove80 keyboard and explains the rationale behind the design.
Published January 23, 2022
TLDR. Key Glove80 ergonomic features are:
- Split so that halves can be repositioned to minimize ulnar deviation, which causes carpal tunnel
- Neutral tilt to minimize wrist extension (wrist bending upwards)
- Adjustable tenting to minimize forearm pronation
- As low profile as possible to avoid forearm bending upwards or wrist extension
- Contoured keywell and innovative thumb cluster for comfortable reach of all keys to reduce finger and thumb strain and stress
- All ergonomic features working together holistically to allow for palm resting on palm rest while typing (should you want to) to allow you to relax your arms and shoulders while typing
In this post I will try to describe the ergonomics design of Glove80 and explain the rationale behind the design. But before we do that, lets have a look at what typing is like on a Glove80.
A well designed keyboard can help you to maintain a good posture and comfort to avoid many common causes of RSI traditionally associated with keyboards.
Ulnar deviation happens when the wrist is bent outwards. It is a common cause of carpal tunnel syndrome, which is caused by pressure on the median nerve. On a standard staggered row keyboard, because of the straight rows, the wrists are forced into a position of ulnar deviation. A split keyboard, such as Glove80, allows you to reposition the keyboard halves wherever you like, such that the wrists are straight when viewed above.
Glove80’s ability to reposition the halves has another advantage. The halves can be positioned further apart, to eliminate the need to round the shoulders, which helps to keep the shoulder relaxed.
Wrist extension happens when the wrist is bent upwards. This bending can greatly reduce the blood flow, and is a common cause for wrist pain and fatigue. Glove80 is designed with a sculpted palm rest such that the wrist is straight when viewed sideways (i.e. no wrist extension), when the palm is resting on the palm rest and your forearm is horizontal. This is called a neutral tilt. Glove80 is one of the very few keyboards that offer a neutral tilt typing position.
This brings us to the next point. It is generally recommended that the forearm should be held at a horizontal position and should never be tilting upwards. Likewise, as we discussed prior, the wrists should not be bent upwards. To allow for the horizontal arm position and no wrist extension, the keyboard (specifically the top of the keycaps) must be low enough.
Unfortunately the amount of space between the hands and your thigh is extremely limited, and that space needs to accommodate the table, keyboard and still leave enough wriggle room for your legs. This is the reason why we did everything to make Glove80 so low profile.
Glove80 uses premium low profile Kailh Choc switches. The lowest keys “D” and “K” are an incredible 20mm (0.8 inch) from top of the keycap to the table (try measuring your current keyboard). Furthermore, we designed a tenting system that adds no extra height, unlike the tenting kits of many other ergonomic keyboards.
So what’s the tenting system? If you press your palm flat on your desk and hold it there for a few minutes, you will feel tension on your forearms and you are experiencing forearm pronation. If you rotate your palms such that your thumb points slightly or more into the air, you will find the position more comfortable. This is the purpose of tenting.
By default, Glove80 has a tenting angle that is comfortable for most people. However we found that this is one variable that differs greatly between users. So we built a clever tenting system into Glove80. The legs of Glove80 can be extended to change the tenting angle of the keyboard, with infinite levels of adjustments. Unlike many other ergonomic keyboards, the tenting kit is integrated and adds no extra height.
The finger keys for Glove80 are arranged in columns to minimize sideways finger movements and the compensating wrist “wriggling”.
Glove80 has a contoured keywell that is shaped to follow the curves your fingertips draw when you curl your fingers. The contoured keywell minimizes the finger motions you need to press a key, and so allows you to type faster and with less fatigue. Compared to a flat keyboard, a contoured keywell minimizes the need to move your palm.
Glove80 has an innovative design for the thumb keys. Our thumbs are our strongest digits, and are underutilized on most keyboards. Unlike other thumb cluster designs, Glove80 offers comfortable access to 6 thumb keys per thumb so you can relieve the workload on other fingers, especially the pinkies. With 12 thumb keys altogether, the thumbs can handle the modifiers and other common non-alpha keys like space, return, delete and backspace.
For most people, of all the thumb joint motions, the flexion-extension motion (sweeping along roughly the palm plane) of the carpometacarpal (CMC) joint is the most comfortable and with the greatest reach. The CMC joint of the thumb is the joint located at the very base of the thumb.
With a well designed contoured key well, the palm hardly ever has to move, so effectively the CMC thumb joint stays at one place. Glove80 is designed to take advantage of that, so that you can reach every thumb key simply by drawing an arc with the CMC joint as the centre, without stretching your thumb or moving your palm much if at all.
However there is more to the whole than just the parts. These Glove80 ergonomic features work together. Because the palm hardly ever had to move to reach the finger keys and the palm keys, a user could choose to rest the palms on the palm rests while typing, which allows the arms and shoulder to remain relaxed.
Wow, you made it to the end. Thank you for reading!
Perhaps we should have another look at a Glove80 typing test to see how Glove80 ergonomics work in practice.
If you want to know how we create and test the ergonomic designs, please check out RSI and how the "ultimate" ergonomic keyboard is created through 500+ A/B ergonomic testing experiments.