| Final Design Concepts

Materials Used

Nylon is a popular material for making bags due to its many benefits. However, the properties of nylon suitable for bags can vary depending on the density, weave and processing of the fabric.

Advantages of nylon for bags:

• Durability and wear resistance: Nylon is strong enough to withstand daily use, carrying loads and various mechanical impacts. It is resistant to abrasion and tearing, which makes bags made from it durable.
• Lightweight: Nylon bags are lightweight, which makes them comfortable to carry. This is especially important for large bags that need to be carried on the shoulder or back.
• Water resistance: Many types of nylon are water-repellent, although the degree of waterproofness can vary. This protects the contents of the bag from rain and moisture. Special impregnations can increase water resistance.
• Easy to care for: Nylon is easy to clean, usually wiping with a damp cloth is enough. Many nylon bags are machine washable, although it is always worth checking the manufacturer’s recommendations.
• Affordable: Nylon is a relatively inexpensive material, making bags made from it affordable to a wide range of consumers.
• Variety of colors and textures: Nylon can be dyed in a variety of colors and textures, allowing for a variety of bag designs.

Disadvantages of nylon for bags:

• Low breathability: Nylon does not “breathe”, so bags made from it may be less comfortable in hot weather.
• Tendency to pilling: Nylon can form pilling on the surface, especially with prolonged use and friction. Special fabric treatments can reduce this problem.
• Potential for shape loss: Nylon can lose its shape, especially if it does not have an additional rigid base or frame.
• Low elasticity of some types: Some types of nylon are not very elastic, which may limit its use for bags that need to stretch.
  Types of nylon for bags:
  Different types of nylon are used to make bags, differing in density and properties:
• Ripstop nylon: High-strength nylon with reinforcing weave, resistant to tearing.
• Ballistic nylon: Very strong and dense nylon, often used in tactical and tourist bags.
• PU-coated nylon: Nylon with a polyurethane coating, which increases water resistance.

Conclusion:
Stainless steel is an excellent material for shopping cart frames, providing high strength, durability, and corrosion resistance. However, its high cost limits its use to premium models. The choice of material depends on the balance between the required properties and the budget.The choice of nylon for a bag depends on its purpose and the required characteristics. Less dense nylon is suitable for everyday bags, and more durable and wear-resistant nylon is suitable for tourist or sports bags. It is also important to consider the fabric treatment, which affects its water resistance and resistance to pilling.

Stainless steel is a high-quality material that can be used to make shopping cart frames, especially in premium models. It has a number of advantages, but also has some disadvantages.

Composition:
Stainless steels contain at least 10.5% chromium, which ensures their high corrosion resistance. The composition may also include other alloying elements, such as nickel, molybdenum, manganese, titanium and others, which change the properties of steel, improving its strength, hardness, ductility and resistance to certain types of corrosion. Different grades of stainless steel have different properties.
Pros of using stainless steel for a shopping cart frame:

• High corrosion resistance: This is the main advantage of stainless steel. It is resistant to rust and moisture, making it an ideal choice for carts that will be used outdoors or in high humidity conditions. It does not require additional coating to protect against corrosion, which makes it easy to maintain.
• High strength: Stainless steel has high tensile and bending strength, withstanding significant loads. Stainless steel frames are more resistant to deformation.
• Durability: Due to their high strength and corrosion resistance, trolleys with stainless steel frames last significantly longer than similar ones made from other materials.
• Hygiene: Stainless steel is easy to clean and disinfect, which is important for trolleys used to transport food or medical supplies.
• Aesthetic appearance: Stainless steel has an attractive appearance, giving the trolley an elegant look.

Disadvantages of using stainless steel for a trolley bag frame:

• High cost: This is the most significant disadvantage. Stainless steel is significantly more expensive than low-carbon or alloy steel.
• Difficulty of processing: Stainless steel is more difficult to process than low-carbon steel. It requires special equipment and tools. Welding can also be more difficult and require special skills.
• Hardness: High hardness can be both an advantage (wear resistance) and a disadvantage (difficulty of processing, tendency to crack under sharp impacts).
• Weight: Although stainless steel has a higher strength to weight ratio than mild steel, it is still heavier than aluminum.

Conclusion:
Stainless steel is an excellent material for shopping cart frames, providing high strength, durability, and corrosion resistance. However, its high cost limits its use to premium models. The choice of material depends on the balance between the required properties and the budget.

Polypropylene (PP) is a common plastic often used to make shopping cart handles, especially in budget models. It is chosen due to its affordable price and acceptable performance characteristics.
Properties of polypropylene:

• Strength: Polypropylene is strong enough for shopping cart handles that can withstand moderate loads. It is fairly resistant to bending and twisting. However, excessive loads may cause deformation or breakage.
• Lightweight: Polypropylene has a low density, which makes the handles lightweight and comfortable to use. This is especially important for shopping carts that often have to be carried over long distances.
• Rigidity: Polypropylene is quite rigid, which provides the handle with the necessary shape and stability.
• Impact resistance: It has moderate impact resistance. It can withstand minor impacts, but strong impacts can cause damage.
• Chemical resistance: Polypropylene is fairly resistant to many chemicals, making it suitable for use in a variety of conditions.
• Temperature Resistance: Can withstand moderate temperatures, but may warp or lose strength if exposed to high temperatures for long periods of time. May become more brittle at low temperatures.
• Processability: Polypropylene is easy to process, allowing handles to be made in a variety of shapes and designs. Injection molding is the most common method of producing polypropylene handles.
• Cost: Polypropylene is a relatively inexpensive plastic, making it a cost-effective option for mass production.
  Pros of Using Polypropylene for Shopping Cart Handles:
• Low Cost: Less expensive than many other plastics used for shopping carts.
• Lightweight: Reduces the overall weight of the cart.
• Durable for Moderate Loads: Suitable for carts with light-duty contents.
• Easy to Manufacture: Easy to process and mold.

Cons of Using Polypropylene for Shopping Cart Handles:

• Low Impact Resistance: May break if subjected to strong impacts.
• Tendency to deform at high temperatures: This should be taken into account when storing and using the trolley.
• Low UV resistance: May fade in the sun.
• May become brittle at low temperatures: This should be taken into account in winter.

Conclusion:
Polypropylene is a suitable material for trolley handles, especially in budget models where a combination of lightness, sufficient strength and low price is required. However, for trolleys with heavy loads or for use in extreme conditions, it is better to use more durable plastics, such as ABS plastic or reinforced polyamide.

ELECTRIC TROLLEY BAG FOR THE ELDERLY

DESCRIPTION

An electric trolley bag on wheels is the best option for long trips with a lot of things. The trolley bag is also convenient for making daily purchases in stores – it is convenient to take with you both when traveling by private transport and when traveling by public transport. Compact trolley bags do not take up much space, and the ease of transportation makes them convenient, including for walking visits to stores. Such a bag on wheels provides effortless transportation of various things. When you want to stop, the shopping trolley bag on wheels can be placed in a stable position, and you do not need to support it in case of a fall – it is specially designed so that it does not bend or move from its place even on an uneven and inclined surface. Each cell of the bag is equipped with a smart watch, which can be used if necessary. On ru
Functions: -frame (trolley) – metal, durable, plastic parts consist of impact-resistant, frost-resistant material. It rests on 3 wheels and a footrest that folds when necessary.
Can be used as a shopping cart: -handle – finished with plastic. The handle folds and is height-adjustable; -there is a screen on the handle that displays such functions of the bag as: weight measurement, bag lock mode, wheel lock mode, turning on the flashlights, switching to manual mode (since the bag is electric, it needs to be charged, but there are times when they forget to do this. Therefore, you can turn on the manual mode and push the cart yourself). There is also an emergency braking button on the handle; -wheels – cast. Only 3 wheels (diameter 17 cm). Such wheels will allow you to lift the cart up the stairs; -bags – hold their shape well due to the dense internal insert. The bag itself is soft, made of nylon (see the properties of nylon above). The top edge is pulled together with a drawstring with a clasp, a lid is thrown on top (with a magnetic clasp, which can be locked if necessary. Only the owner of the trolley bag can open it); -one of the bags is lined with a material on the inside to maintain the temperature. Therefore, you can put frozen foods or those that spoil quickly (meat, fish, etc.) there; -the model additionally has an external pocket with a zipper, a hook for a bag, a hook for an umbrella and a stand for a glass or bottle; -equipped with a folding chair; -suitable for – elderly people, as well as for anyone who wants to keep their back healthy; -frame – steel pipe, diameter 16 mm, painted dark gray.

Cart size	970 х 340 х 560(height x width x length)
Bag size 1 Bag size 2 Bag size 3	350 х 320 х 200(h x w x l) 300 х 320 х 200(h x w x l) 290 х 320 х 200(h x w x l)
Weight of the trolley with the bag	2.5