Cargo Weight, Center of Mass and Backhaul

Episode six. I will try to explain the overall picture of digitization from the Mouse Scale trademark without marketing.

You probably already know what our Light version gives you for one dollar a month. It is like a bicycle, where the driver controls the axle weights and a good balance himself. That is great, but carriers all over the world need to know more about the weight of the cargo in the trailer, and preferably the position of its center of mass.

Built-in scales usually control only the axle loads.

That is why we created the Pro version, which uses all the important variable parameters of the truck and trailer for a full weight diagnostic. Mouse Scale Pro provides more than two dozen useful results about the weight of the truck, the trailer, and the cargo. Compared with a bicycle, it is like a helicopter. But don't relax because you will still have to keep pedaling until truck manufacturers allow an automatic system to be built on onboard computers with extended peripherals.

At the same time, we recommend that drivers and carriers support the use of a quality handheld pressure gauge in trailer suspensions to keep the driver's important role in load control and their right to a decent reward. It is a new, inexpensive, and good driver's method. Let it be so until autonomous trucks spread, which unfortunately will replace drivers.

It's time to upgrade the outdated field of load control to help develop backhaul and partial load transportation. Here is a real logistics problem. How can we determine the weight of the cargo in a trailer, the location of its center of mass, and the truck's remaining payload capacity?

Look, it's really not that complicated. To solve one white face of a Rubik's Cube, you don't have to know how to solve the entire cube. First, let's imagine that we have all the necessary knowledge, resources, and equipment. Let's start with a certified scale.

First, we need to digitize trucks and trailers a little. For each truck, it is enough to determine its weight once with full diesel and DEF tanks and a known driver weight. For the trailer, we need to know its empty weight, as well as the weight on its tandems when they are in the forward position. After that, the problem becomes very simple.

We weigh the loaded truck and trailer on a certified scale and get the weight of all axle groups. Next, we determine the current weight of the truck itself. To do that, we account for the amount of diesel and DEF in the tanks and the weight of the driver and passenger. Beyond that, practically nothing significant changes in the truck's weight.

Now we take the actual combined steer and drive weight from the scale receipt and subtract the current bobtail weight of the truck. That tells us how much of the trailer's weight is transferred to the truck through the fifth wheel. It's simple, and we're already halfway to the solution.

Add the trailer tandem weight to that number, and we get the total weight of the loaded trailer. Subtract the known empty trailer weight, and we get the cargo weight. Carriers around the world need to know more about cargo weight, not just axle weights. In my opinion, this is very simple. Even a fifth grader can understand how to solve this problem.

Now let's talk about real life without a certified scale. We have already shown how to estimate the weight on the truck's drive axles and the trailer tandems using air suspension pressure and PSI gauges. That leaves one more variable, the steer axle weight. American onboard systems are already trying to solve this problem. They use mathematical models with virtual sensors or more expensive solutions with deflection sensors.

I think some of these formulas were developed before smartphones and modern onboard computers became widespread. Therefore, they may not separately account for the distribution of diesel and DEF weight between the truck's axles.

Manufacturers claim steer axle accuracy of approximately two to two and a half percent, or about two hundred forty to three hundred pounds. I have not tested these systems, so I will not judge or criticize their real-world accuracy. But the main point is something else. Even that level of accuracy already allows us to determine cargo weight and estimate the position of its center of mass if we use our proposed digitization approach with known truck and trailer weights.

At Mouse Scale, we use a different analytical approach. We account for the distribution of diesel weight between the axles, the weight of DEF, the driver and passenger, the load transferred through the fifth wheel, and the position of the fifth wheel itself. Based on our long-term observations on a truck in good technical condition, the error in calculating steer axle weight could be around one hundred pounds.

In practice, this logistics problem turns out to be much less complicated than it may seem at first. When I digitized the truck and trailer I drive, we were able to catch about one extra metric ton of undeclared cargo every two months. This was not an overweight issue in terms of legal limits. The actual amount of cargo simply exceeded what was specified in the shipping agreement. To be honest, in those cases, the broker simply paid us extra and I went on my way, but that extra work was compensated.

We don't want to overload drivers with a complicated description of the mathematical model. The important thing is that the model exists and can be tested in practice, including during the free trial of Mouse Scale Pro. And where is the cargo's center of mass? That is the next, and especially interesting, problem. Knowing the center of mass can be important for developing backhaul and partial load transportation.

If there is free space and remaining payload capacity in the trailer, it is not enough to know only how much additional cargo can be loaded We also need to know where to place that additional cargo. Will it be safe from the standpoint of load balance? Will the truck remain within legal weight limits?

That is why during digitization, it is useful to weigh the empty trailer once with the tandems in a known forward position. If the trailer is partially loaded, the tandems can also be moved to that same known forward position. For a partially loaded trailer, this can often help achieve good load balance and good maneuverability.

Next, we determine two values. How much did the cargo increase the load on the fifth wheel? And how much did it increase the load on the trailer tandems? If we know the distance from the kingpin to the center of the tandems in the forward position, then using simple mechanics, we can calculate the location of the cargo center of mass inside the trailer.

This gives us three key results. How much does the cargo weigh? Where is its center of mass? And how much additional cargo can the truck safely and legally carry?

And that opens up an entirely new logistics opportunity. If the system knows the weight of the existing cargo, its center of mass, the remaining payload capacity, and the available space inside the trailer, it can help determine what additional backhaul freight can be picked up and where it should be placed.

This kind of technology could become one of the foundations of efficient backhaul and partial load transportation. Better use the payload capacity we already have, move more freight with fewer trips, and at the same time maintain safe and legal load distribution.

Today, much of this work is done by dispatchers, but they often do not have sufficiently accurate information about a specific truck, trailer, and load. So it makes sense to digitize trucks, make more money, and haul less air. This matters to carriers and drivers, to the country, and to the environment. A logistics problem that seems complicated at first becomes much simpler when we break it down into a few clear parts.

Raise the importance of the driver's work. Demand a decent reward for saving resources. Reduce the risk of crashes and cut harmful exhaust emissions. You will succeed because mouse scale is better.