The Company:
The company is a major manufacturer of high-tech bicycles with a worldwide distributorship and many professional endorsements. Their mission is to promote bike riding through innovative products and exceptional care for their dealers and customers.
The Challenge:
In their ongoing quest to improve the efficiency and aerodynamics of their bikes, company engineers have been testing them in a wind tunnel since 2000. The goal is to improve design to reduce drag, so the same amount of power will create more speed and better air flow. The wind tunnel testing works well for mechanical assemblies like the bikes and components. However, in order to obtain truly realistic results, the interaction between the bike and the rider must also be factored into any wind resistance testing plan.
Unfortunately, the wind tunnel environment proved to be harsh and tiring for a human rider. It was very difficult for a real rider to maintain an unvarying position for an entire day of testing, and therefore required expensive multiple runs and extended data sampling to ensure that the results were consistent. The company decided to create a life-sized, lifelike articulated foam figure to be used in their wind tunnel testing program. To create a meaningful simulation and obtain accurate specs, the figure needed to be symmetrical and in exactly the same position for each test event.
Off-the-shelf mannequins were not capable of assuming the position of a racing bicyclist; their backs and hips did not flex enough, and their toes did not articulate from the feet to connect with the pedals correctly. Also, such a figure would hinge in and out of position randomly at the moveable joints, so consistency was not assured. They needed an identically shaped figure on every bike to remove the rider drag variability from the wind tunnel testing.
The bike manufacturer found GKS through an Internet search for 3D laser scanning and carefully discussed the scanning options with the engineers until they came up with an efficient plan to conduct the laser scanning bike-and-rider project. Consistency, stability, and stillness of the rider’s position were critical to the success of collecting accurate scan data, and eventually building a foam model.
The Process:
Since the position of the rider was so important to obtaining a viable model, the physical set-up of the bike and person took some forethought and precision. The difficulty in scanning people is that they tend to move because of muscle spasms and/or fatigue, so the challenge was to make the rider as comfortable as possible to minimize movement for the approximately 15 minutes it would take to scan him thoroughly. To maintain the static position of the rider, the bike was stabilized in a bike stand. Other moving parts, such as the pedals, were braced or strapped down. Another unique set-up item was the rider’s clothing: he wore a white full bodysuit to help the scanner pick up details of the body’s basic geometry.
GKS engineers employed the Laser Design scanning system using the Platimum 8’ FaroArm and theSLP-2000 laser probe, industry’s longest line laser probe (accurate to 127 m) to precisely scan the free-form profile of the bicycle and rider. The 8” laser line of the SLP-2000 probe meant that more data could be collected at a time, reducing the time it took to collect all the data. Also, the Laser Design scanning system using the portable and flexible FaroArm made it possible to capture data from all the nooks and crannies found on the bicycle and rider.
Read More: GKS Scanning Speed and Accuracy Prevail to Scan Bike and Rider for the Windiest Conditions