WiScooter Manufacturing Details Spring 2023

WiScooter Manufacturing Details ISyE 350: Industrial and Systems Engineering Junior Design Laboratory Professor McDonald, Spring 2023 Product Demand and Seasonality: WiScooter, a Wisconsin company currently has two core product offerings however, the company wants future design considerations to include modifications to products. WiScooter values fabrication and assembly flexibility since order quantities for specific customers are rarely identical. For example, in the next few years WiScooter may begin to customize scooters for ride-sharing companies and personal customers with specific logos and features.  Personal scooters: Tubular steel is cut and welded for the shaft and handlebars in three different sizes, then attached to a metal base that houses the wheels, electric motor, battery, breaks, and printed circuit board. Personal scooters are powder coated with the WiScooter logo and model number prior to assembly. Once assembled, they are packed in cardboard boxes and placed in finished good inventory.  Commercial Scooters follow a similar manufacturing process, but generally have larger wheels, more powerful electric motors, longer-lasting batteries and have simplified painting and cosmetic features. All commercial scooters come in one size and are equivalent to the large personal scooter. WiScooter has built strong relationships with a variety of local Wisconsin suppliers that it intends to continue utilizing in the future. The company receives tubular aluminum, blank printed circuit boards (PCB), PCB components, rubber materials, wheels, motors and batteries from a small number of local suppliers. The suppliers have unlimited capacity for WiScooter and can support replenishment shipments reliably within their specified lead times. Table 1: Simplified Bill of Materials (BOM) for all five SKUs Bill Of Materials Product Name Unit Weight (lbs) Electric Motors Motor Size Battery Size Stem Lenth (inches) Steel Housing (sq ft) Wheel Size Color SKUC1 Commercial Scooter (large motor) 39.8 1 Large Small 36 6 8" White (primer) SKUC2 Commercial Scooter (long life; large motor) 43.3 1 Large Large 36 6 8" White (primer) SKUP 1 Small Personal Scooter (red) 24.9 1 Small Small 28 4 6" Red SKUP 2 Medium Personal Scooter (blue) 27.6 1 Small Small 32 5 6" Blue SKUP 3 Large Personal Scooter (long-life; black) 33.7 1 Large Large 36 6 8" Black WiScooter is experiencing varying growth across their product offerings. Commercial scooters are growing consistently, especially in southern states in the United States and large ride- sharing companies typically order large quantities of commercial scooters at a time (especially when they expand into new cities). It is not uncommon for large orders for commercial scooters to be placed without warning and WiScooter must place products on backorder. Personal scooters are projected to rapidly increase in demand. More WiScooter customers place orders 1

in the summer months during warmer temperatures. As a result, demand for all five products is seasonal, which can increase demand by up to 40% in peak summer months compared to winter months. The facility needs to accommodate changes in demand, either through pre- building products and housing them in warehousing or increasing production capacity and production lead times (or both). JanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJulyJanuaryJuly 0 5000 10000 15000 20000 25000 SKUP1 SKUP2 SKUP3 SKUC1 SKUC2 Figure 1: Projected Demand over the next 10 years 2

2. Current Facility Design (400’ x 300’): Currently, WiScooter Inc. has a 120,000 sq ft dual-purpose facility with the following layout. The Raw material and finished good inventory space can be outsourced to a local distribution center. The newly available space can be used for expansion of fabrication and assembly processes. There are currently three receiving and three shipping dock doors. The height of the facility is 24 ft. - Note: receiving and shipping space will still be needed in this facility. Figure 4: Current Wisconsin Dual-Purpose Facility 3. Bill of Materials, Supplier Information & Lead Times The following table details the bill of materials (BOM) for all five product SKUs. The BOM includes quantity per unit, supplier of components, component lead times, minimum quantities WiScooter can order at one time, and the respective costs and inventory space per order. 4

Table 2: Detailed Bill of Materials for all five product SKUs 5

8. Machinery: Table 3: Mapping of fabrication processes and respective machinery requirements for current and planned SKUs 7

Machinery Options and Production Information: Table 4: Machine options with throughput, cycle time, changeover time, maintenance time, size, dimension and defect rate for each option. Machine Option Throughput (units/hour) Cycle Time (min/unit) Changeover Time (mintues) Reason for Changeover: Shift Throughput (units/8 hours) Maintenance Time (minutes per 8 hours) % Time Running (per 8 hour shift) (No changeovers) Throughput with Maintenance (per 8 hour shift) Size (Sq ft) Dimensions Defect Rate (%) Number of Machines in current facility Dry Oven Small 200 0.3 0 1600 45 0.90625 1450 1500 30x50 0.0% 2 Forming Machine Standard 250 0.24 10 Industrial vs. Standard Metal 2000 15 0.96875 1937.5 2500 50x50 1.0% 1 Functional Testing Machine (motor & brakes) Standard 500 0.12 0 4000 0 1 4000 450 30x15 0.0% 1 Functional Testing Machine (PCB) Standard 500 0.12 0 4000 0 1 4000 450 30x15 0.0% 1 Laser Cutter (handle cars, stem, support bar, me Medium 250 0.24 10 Industrial vs. Standard Metal 2000 15 0.96875 1937.5 2500 50x50 0.5% 3 Manual Grinder 1 employee 100 0.6 0 800 0 1 800 450 22.5x20 1.0% 3 Manual Touch-Up (powder coat) 1 employee 250 0.24 10 Different Color Paint 2000 30 0.9375 1875 450 22.5x20 0.0% 1 Manual Touch-Up (primer) 1 employee 300 0.2 0 2400 30 0.9375 2250 450 22.5x20 0.0% 1 Manual Welding (handlebars) 1 employee 125 0.48 0 1000 0 1 1000 450 22.5x20 1.0% 2 Manual Welding (wheel mount) 1 employee 100 0.6 0 800 0 1 800 450 22.5x20 1.0% 2 Paint Booth Small 225 0.266666667 20 Different Color Paint 1800 60 0.875 1575 3500 50x70 1.0% 2 Pick & Place Machine Standard 60 1 0 480 0 1 480 450 30x15 3.0% 3 Press Break Manual 60 1 0 480 0 1 480 1000 40x25 5.0% 3 Punch Press Manual 60 1 0 480 0 1 480 600 20x30 5.0% 3 Solder Paste Machine Standard 500 0.12 0 4000 0 1 4000 450 30x15 1.0% 1 Washing Station Small 200 0.3 0 1600 45 0.90625 1450 1500 30x50 0.0% 1 Welding (handlebars to stem, stem to support b 1 employee 300 0.2 0 2400 0 1 2400 450 30x15 1.0% 2 Combine & Install Folding Mechanism 1 employee 150 0.4 0 1200 0 1 1200 450 30x15 0.0% 1 9. Shipping & Receiving Parameters: Standard 53’ semi-truck trailers dock at the shipping and receiving doors for pick-ups and drop offs. Finished goods vary in size depending on how products fit on pallets (see above). There are 13 pallet locations within a trailer and have the height clearance to stack 2 pallets, for a maximum capacity of 26 pallets. In the design of the facility, consider the flow of materials from raw materials and components received to finished goods shipped out in pallets. Also consider how employees will access this inventory as the product move through the fabrication and assembly processes. 10. Inventory Parameters:  Twelve finished 28” stem length personal scooters (SKU 1) can fit on a standard 4’x 4’ pallet and can be stacked two pallets high within a shipping container or semi- truck trailer  Nine finished 32” stem length personal scooters (SKU 2) can fit on a standard 4’x 4’ pallet and can be stacked two pallets high within a shipping container or semi-truck trailer  Six finished 36” stem length or professional scooters (SKU 3,4 or 5) can fit on a standard 4’x 4’ pallet and can be stacked two pallets high within a shipping container or semi-truck trailer  Inventory shelving can stack pallets three pallets high (1 pallet per shelf) and be stored and retrieved with forklifts  Building heights must be greater than or equal to 24’ high to support shelving three pallets high and 18’ to support shelving two pallets high. 8