Blog #1 - Luggage Lifting Device

  Background and Motivation

Many travelers regularly encounter stairs in places such as airports, train stations, subways, and

hotels when elevators are unavailable or out of service. In these situations, moving a large

suitcase becomes difficult and unsafe. Most checked suitcases weigh up to 50 lb and are

designed to roll only on flat surfaces. When faced with stairs, users must lift the full weight of

the suitcase while maintaining balance on narrow steps, which increases physical strain and the

risk of injury. According to the American Academy of Orthopedic Surgeons, this has resulted in 85,000 

people being sent to the emergency room due to luggage related injuries as recently as 2017.  This 

problem is especially challenging for smaller or petite users and those with limited lifting strength. Of 

those who suffered from luggage related shoulder injuries, around 60% were female and over the age 

of 50. A mechanical solution that assists users in moving suitcases on stairs could reduce physical  

effort, improve safety, and make travel more accessible.

Problem Statement

The problem addressed in this project is the lack of a safe and practical way to move heavy

wheeled suitcases up and down stairs without fully lifting them. Typical suitcases weigh between

20–30 kg and must comply with airline check-in requirements, including a maximum size of 62

linear inches (L+ W+ H) and a standard weight limit of 50 lb (with an upper limit of 70 lb). Stair 

heights commonly range from 5.5 to 7.5 inches, which makes stability difficult during both ascent and

descent. Our team is focusing on this problem because it directly affects traveler safety and

independence. Project goals will be defined by reducing the force required from the user,

improving stability on stairs, and ensuring compatibility with airline size and durability

requirements.

Expected Challenges

A major challenge is keeping the suitcase stable on stairs, since a tall and heavy suitcase can

easily tip or slip. Going down stairs is especially risky because gravity can cause the suitcase to

move too fast and become hard to control. Another challenge is reducing the effort required from

the user without adding too much weight, which could cause the suitcase to exceed airline limits.

Exposed wheels or mechanisms that stick out can also be damaged during airline baggage

handling, where luggage is often dropped or hit during transport as it shown in figure 2. 

For this reason, the system must be easy to use and designed so that any stair-assist parts can retract or 

be protected during normal travel.

Constraint	Effect	Approach
Stability on stairs	A tall, heavy suitcase can tip sideways or backward on narrow steps	Use a wide wheel base, low center of gravity, and multi-wheel contact with the stairs
Uncontrolled motion going down stairs	Gravity can cause the suitcase to slide, increasing injury risk	Use wheel geometry that slows descent and allows step-by-step movement
Different stair heights	Stairs vary slightly in height between buildings	Design fixed wheel geometry that works over a standard stair height range
Damage during airline handling	Checked luggage is dropped and impacted during transfers	Protect or fully retract wheels and mechanisms inside the suitcase shell
Added system weight	Extra mechanisms increase total luggage weight	Use lightweight materials and minimize part count
Wear and long-term durability	Repeated stair use and impacts cause wear	Select durable materials and design for repeated loading cycles
Ease of use	Travelers may be tired or unfamiliar with the system	Make deployment intuitive with minimal steps or adjustments
Airline size limits	Protruding parts may exceed airline size restrictions	Use a retractable or fold-in wheel system that fits within the suitcase outline

Table 1 - List of Challenges

Figure 1 - Physical Portrayal of the Problem 

Figure 2 - Damaged luggage during transportation

Sources: 

[1] Don’t let injuries ruin your holidays avoid suitcase strain. Don’t let injuries ruin your holidays Avoid suitcase strain. (2018, November 8). https://www.aaos.org/aaos-home/newsroom/press-releases/luggage-safety-tips/

[2] Pirruccio K, Kelly JD. Shoulder injuries associated with handling luggage presenting to U.S. emergency departments: 2003-2017. Work. 2020;66(3):603-609. doi: 10.3233/WOR-203202. PMID: 32623421.