What do you think of when you read the word “swaddle”? Most will think about swaddling a baby in a blanket as a way to soothe them, but an adult swaddle can have a soothing effect as well. Weighted blankets –when appropriately designed — can provide an adult swaddle that reduces or eliminates common mental health symptoms. Read more to find out how we engineered Truhugs Two.
Improving pressure distribution
Pressure equals weight divided by a weighted blanket’s surface area. Pressure in a weighted blanket is applied with weighted beads –usually glass or plastic– stuck inside small stitched grids. In order to help illustrate this concept, let’s start by looking at the most typical mass production weighted blanket that has had its quality literally destroyed by cost competition.
The Most Inferior: Traditional Low-Cost Weighted Blankets with Large Grids and No Batting
Note how above, when the bed is made…that the big grids with lack of filling don’t really matter on a flat surface when the bed is made. In the diagram above, with the average shoulder width of American males and females averaging 12 to 14 inches, and the average body circumference around 40 inches, we can deduct that the semi-circumference of the average American adult calculates out to be roughly 28 inches. This means that only one grid of pressure is on you fully, with 2 grids applying weight towards the bed, not on your body. There is a little horizontal vector applying pressure on the body, but not much.
Why large grids contribute to bed slippage
Below, a diagram shows how a large grid weighted blanket even with batting fill will have weight causing the weighted blanket to slip off the bed because there isn’t as much weight on the bed. Batting equals fluffy filling that traps some of the weighted beads inside its web matrix…
The Average Weighted Blankets on the Market Today Lends to Mediocre Adult Swaddle
Fluff helps reduce noise and maximize durability, but only when implemented correctly
This brings us up to our next consideration, which is the next step up, a weighted blanket with large grids and batting. Batting helps inhibit the flow of weighted beads when you adjust at night, and some get stuck in the batting…helping subtly with pressure distribution, but most of it falls on the opposite wall ANYWAY. Batting fibers are fine, so it is impossible for them to trap ALL the weighted beads.
So what is the main point? That when it comes to equal pressure distribution, small grids limit weighted filler movement the most effectively, whereas batting helps by slows the movement rate so that when the beads hit the stitching wall, they aren’t moving so fast that they might break the stitching. The fluff also helps separate the weighted beads so they aren’t hitting the grid stitching walls with high force. This helps improve weighted blanket durability. Most weighted blankets without fluff are built with plastic scrims that help reduce the impact of many weighted beads traveling at high speeds hitting the stitching walls at once. Those that don’t have a scrim and any fluff tend to have many bad reviews of weighted blanket leakage.
Overfilled grids with polyester make the blanket much more rigid and put a strain on the stitching
In the diagram below, you can see how overfilled grids put a strain on stitching by making each grid almost like a balloon that is about to pop.
Why weighted blankets with larger grids require thicker batting to fill their grid volumes
Making grids smaller allows for the use of reduced batting while maintaining fluffiness. As stitching distance decreases, less fluff can be used while still occupying most of the grid volume. This is because there is a direct relationship between how much batting you can wrap and how much cloth you have to wrap it.
The ultimate outcome of this “smaller grid, less batting allowed to maintain fluffiness relationship” is that the blanket traps less heat, wraps your body better, and is thinner for storage.
By decreasing stitching distance (X) you reduce the overall blanket thickness and overall batting that needs to be used to fill a grid. Thus by decreasing grid size and being allowed to use thinner batting the following results occur: (a) Hot air diffuses quicker through thinner batting (defined as less than Y) than thick batting (defined as Y). & (b) The blanket becomes less rigid because a blanket that is less thick is easier to bend than thick batting.
How cheap batting can help make a weighted blanket overly rigid
Many cheaper polyester and micro-polyester battings have short fibers that need to be glued. The whole batting layer ends up this rigid plank that can’t even bend on itself. Natural battings are more supple.
Weighted blankets with smaller grids and no batting are slightly better, but usually require a scrim to maintain the durability
Because there is no batting inside the grids, the weighted beads hit the stitching walls, freely. This causes most manufacturers to put a plastic scrim, which also makes a blanket more rigid and less thermally flexible. The result is a weighted blanket that distributes pressure better, but with less adult swaddle, more noise, and the propensity of overheating.
However, you can clearly see above that one advantage of smaller grids is that the pressure stays on your body much better than big grids. Smaller grids also help reduce weighted blanket slippage better, because more weight is on the bed. This dynamic helps hold the weighted blanket in place instead of having it fall off the bed.
The superior design behind truHugs 2
truHugs 2 is designed with perfectly filled grids and no scrim. The design’s beauty lies in its simplicity and purity.
Summary: comparing different designs with batting and grid sizes
Sensation of weighted beads is mostly dependent on appropriate batting fill.
Durability, equal pressure distribution, and risk of bed slippage (twin) is mostly dependent on grid size.
Thermal regulation and noise reduction is dependent on both batting fill and grid size. Risk of bed slippage (queen) is independent of grid size or batting size.
Grid size and fluffy filling notes
- Risk of bed slippage: As a primary effector, smaller grids reduce sheer force from weighted beads falling off the bed. (A & C > B & D). With less of an impact A > C, and B > D here because batting has weight too, and there is more friction on the bed to hold the blanket in place. Weighted beads are the primary weight in a blanket, not batting, however, batting does have a minor effect on the variance of the outcome.
- The sensation of weighted beads: As a strong effector, sensation of weighted beads is lessened where there is batting fill. (A & B > C & D). Within A & B / C & D, A & C are better than B & D because there are less beads per grid. Proper grid filling has more of an effect on weighted bead sensation than grid size, although if you have large grids with no batting, you will have huge lumps of beads in one corner that you will feel.
- Equal pressure distribution: As a primary effector, smaller grids have a greater impact on equal weight distribution. (A & C > B & D) With a lesser impact, batting also affects pressure distribution by slowing down-weighted bead movement weight during dynamic movement. The stitching walls of a grid absolutely stop weighted bead displacement (limits total range). Batting inhibits weighted bead displacement and weighted beads get stuck….but still the majority of beads go towards the stitched walls.
- Noise during weight readjustment: As a stronger effector, noise readjustment is lessened when there is batting fill and smaller grids. This is because if the beads travel longer distances, they will accelerate and hit the stitched wall all as a group. With batting, the weighted beads have to trickle through the fluffy fibers, slowing their rate of displacement.
- Durability: As a primary effector, smaller grids have a greater impact on durability. (A & C > B & D). With a lesser impact, batting also affects durability. Why? Smaller grids mean more stitched lines overall within a blanket and less glass beads that can forcefully hit a stitched wall per grid. Batting helps decrease acceleration and resulting force on respective stitched walls. However, too much batting puts pressure on stitched walls as well. In addition, if batting is insufficient or has propensity to shrink, over time batting fails to serve its original function.
Improving dynamic flexibility
In this section, we will talk about how close a weighted blanket contours your body and bends when you move.
How the blanket rigidity is determined for different grids and stitching distances
Below, we will illustrate using the most rigid weighted blanket design on the market, the double-stitched design.
Dotted lines show force by the needle during manufacturing. During stitching, 2 needles from the bottom and the top hit and meet to create a stitched line that barely has any thickness with materials stacked in parallel on top of each other as sheets of material. (not represented properly)
These stitched lines are where the blanket bends the easiest because it is where the blanket is thinnest.
Yours have much less cloth X1 than cloth Y1 to meet the stitched grid. (which actually meet in the middle)
This results in X2 pushing on X1 more than Y2 pushes on Y1, resulting in uneven stitching force imbalances that may eventually cause de-threading.
Bending through less batting length will always be easier than greater batting lengths
A diagonal bend through this grid (highlighted in red) would be easier than a vertical bend (blue). This is simply because its easier to bend through less material.
The most rigid weighted blanket quilting style: double-stitched designs
Double-stitched design rigidity and flex color map
As the bend cross more rigid hotspots, the crease becomes harder to bend, especially when crossing perpendicular too many rigid grids and quilting lines. A weighted blanket always bends easiest along its stitching lines. Rigid hotspots increase as the bend increases in length or approach the middle of the blanket.
Below, thin dotted lines signify natural crease spots but notice how even at natural crease spots the blanket is made more rigid by the double stitch. Big dotted lines signify common crease spots that may occur when getting in and out of the blanket, a common activity of daily living. Diagonal creasing is nearly impossible. Double-stitched designs don’t wrap your body as closely.
Rigidity effects from surrounding grids
Because the weighted blanket grid is surrounded by “double-stitched pockets” that are more rigid than itself, overall weighted blanket rigidity is increased dramatically.
The gray light opacity ovals represent creases commonly made during activities of daily living. This diagram helps show how rigidity is increased with every type of common “bedroom activity because the crease has to bend through rigid orange and red ‘mini’ grids between the ‘double’ stitch.
More examples of inferior rigid designs: diamond
Diamond weighted blankets are easier to get in and out of but are harder to sit up in. Increased risk of slippage is present.
Above, notice how a diamond weighted blanket bends easily when you get in and out, but not along the sides of your body, because its forced to bend through batting and stitching tons of times no matter what. Diamond designs thus have a higher propensity to slip off the bed than square or double-stitched designs, because they don’t bend easily around bed frames (vertical or horizontal bends).
Concept check: Do you know where a diamond weighted blanket will most likely bend when you sit up?
Where are creases most likely to occur when creasing easily on stitched lines (where the blanket is minimally thick) is no longer an option and bends are forced to go through the batting fluff? Wherever batting is shorter between stitched lines.
If you already own a diamond grid weighted blanket, you will notice your weighted blanket tends to bend most frequently through the big purple dashed line instead of the blue. Because the bend is at a small corner, it bends easier than through the middle of the entire batting piece inside each grid. Bent batting axis length at a corner (purple) < bent batting axis length through the middle (blue).
More examples of inferior designs: traditional square
The traditional square design is less rigid when attempting to sit up. Also, creases around the bed frame edge better. However, it’s harder to get in and out of bed. Uses the same ‘batting’ bending principles as ‘diamond’ designs, rigidity patterns are reversed. This was an inferior design present in truHugs 1 that we improved for this year.
Showing how we designed pressure and drape
We will start by looking at SOLO as an example. Looking at the colored stitching regions, we have red, green and blue. The functions of each of the curvatures are described below:
SOLO: Curves of different sizes
Explanation of amplitudes
- Red zone: Curvature amplitude maximized when only the front side of a side sleeper (vertical position) can rest underneath these grids. When side sleeping, the front side of most side sleepers is more vertically oriented than the back.
- Green zone: Curve amplitude weight increased slightly to help push weight higher on a person’s side over the edge onto the most horizontal body plane.
- Blue zone: Most dynamically flexible because of lower curve amplitude. Grids surrounded by this pattern are most frequently on a horizontal planar surface, negating the positive effects of increased curve amplitudes.
Side view to help explain
Curve amplitude increases as grids are more likely to be vertically oriented during sleep or daily use. Curves highlighted in red have the greatest amplitude, then green, then blue. This helps trap more weighted beads above natural creases while pushing weighted beads up even more. Adaptive to side sleeping, back sleeping, not slipping off the bed, keeping more weight on the bed itself, and reducing feelings of slippage. When grids are flat on a horizontal surface, the curves don’t really affect weight distribution. Smaller curves grant increased weighted blanket dynamic flexibility when there is a high possibility of the presence of a moving body underneath.
As we learned earlier, the more material a blanket has to crease through during a bend, the harder it is to bend at that location. Our new product curved stitching lines decrease flexural rigidity over the square and double stitched designs while getting in and out of bed.
The small gridding increase frequency of “easy to crease “line occurrences, helping the blanket drape better. Smaller gridding also allows less batting to be used, and less thick batting bends easier.
The horizontal stitching perpendicular to body orientation allows for flexural rigidity while sitting up, another common activity of daily living.
Natural bends occur at the dotted lines. Notice how the blanket is dynamically flexible to bends of all planes. Our prior square design was more rigid when making diagonal bends because diagonal bends required bending through batting….there was no other options. Now if you follow the diagonal bend lines, about half rests on where the blanket is least thick (on the curved line itself). The rest goes through a small batting width (on the axis). Indeed, you should now know that these are the place where the blanket will naturally bend when getting in and out of bed.
Another important point to note is how our decreased stitching distance allows these bends to occur more frequently. Thus, because of a cumulation of our stitched design, smaller grids, and thinner batting built from the right materials, our blanket really wraps your body better…as evidenced by our beautiful marketing pictures that show superior drape. DUO is engineered with more drape than SOLO, as this drape helps keep extra-large DUO anchored on the bed. Further, this dynamic allows individuals to adjust their portion without disturbing the other. SOLO needs to be kept smaller because smaller beds have smaller surface areas to generate frictional forces that anchor the weighted blanket in place.
Grid proliferation: wrapping your side close, preventing weighted blanket slippage by pushing more weight on the bed mattress
On a more granular level, truHugs will never bend through sub-grid one (red line), infrequently through sub grid 2 (orange line), and most likely where the wave peaks are (green lines).
How Solo wraps whatever object it is on
On your body when you are sleeping on your back
When sleeping on your side
Over 70% of us sleep on our sides. That is why Solo has higher curved amplitudes, to increase the area in which weighted beads can be trapped. No matter which side you sleep on, Solo’s green amplitudes are calculated based on how much space and how bent most people’s arms are when they are naturally at rest. The triceps produce maximal force when the elbow joint is at an optimal resting length of 85-90 degrees. This data will be linked to the final post soon. Our muscles are like multiple pieces of parallel velcro, and the more overlap there is between the velcro (our muscle fibers), the easier it is to produce the same force with less perceived effort. Deconditioned people will have a smaller natural resting elbow joint angle whereas conditioned athletic yoga athletes will have more. Based on mathematical calculations such as these, we calculated where the body would most likely end up on different bed frames after turning on its side.
DUO: Sizing our king size for ease of adjustment, slippage reduction, and adaptation to multiple bed frames
Sized around adult bodies and the ways they sleep
If you look, we sized DUO to be adequate for 2 adults. The curvatures assume a maximum body circumference of 42 inches which was pulled from body anthropometric studies in public health.
Headboard view: King size bed – not in use
Note how here, there is no slippage on a king-size bed. The blanket dimensions don’t surpass the dimensions of an average American mattress, so whether your mattress is on a box frame or not won’t really affect how DUO rests when it’s not really being used.
Headboard view: King size bed – in use
Headboard view: Queen size bed – not in use
In full transparency, this is what our blanket looks like when made on a queen-size bed. It probably looks pretty ugly with all the overhang unless you have a box spring, or you fold DUO when its not in use.
Headboard view: Queen size bed – in use
Thermal regulation notes
Here, we take a step back and look at the weighted blanket as a whole first.
Always view the weighted blanket as a multi-layered assembly…because most people only advertise the surface fabrics. Below is how a weighted blanket is typically layered during manufacturing……
Again, below is what a weighted blanket looks like post stitching.
Why glass beads don’t really affect thermal regulation
Although batting really helps inhibit the rate of displacement and some weighted beads do get stuck in the empty spaces of batting, if the blanket is vertically oriented beyond 45 degrees, the stitched grid walls are what stops most of the beads. Because glass beads are dispersed throughout batting and mostly in a corner, heat can dissipate through the fabrics and the batting without needing to be absorbed and released by the glass beads. This is why glass beads are not considered a real weighted blanket layer.
What thermal diffusion through one grid looks like
To be continued…thanks for reading!