Dwi Basuki Wibowo

Estimation of foot pressure from human footprint depths using 3D scanner

The analysis of normal and pathological variation in human foot morphology is central to several biomedical disciplines, including orthopedics, orthotic design, sports sciences, and physical anthropology, and it is also important for efficient footwear design. A classic and frequently used approach to study foot morphology is analysis of the footprint shape and footprint depth. Footprints are relatively easy to produce and to measure, and they can be preserved naturally in different soils. In this study, we need to correlate footprint depth with corresponding foot pressure of individual using 3D scanner. Several approaches are used for modeling and estimating footprint depths and foot pressures. The deepest footprint point is calculated from z max coordinate-z min coordinate and the average of foot pressure is calculated from GRF divided to foot area contact and identical with the average of footprint depth. Evaluation of footprint depth was found from importing 3D scanner file (dxf) in AutoCAD, the z-coo...

Estimation of calcaneal loading during standing from human footprint depths using 3D scanner

This research studies the relationship between footprint depths and load in the calcaneal area when human standing in an upright posture. Footprint depths are deformation in the calcaneal area obtained from the z-value extraction of the Boolean operation acquired from unloaded foot scanning using 3D scanner and loaded foot using foot plantar scanner. To compare peak loads estimated from footprint depth maximum, force sensing resistor (FSR) sensor is attached over the shoe insole with zero heel height in the calcaneal area. Twenty participants were selected from students of Mechanical Engineering Department Diponegoro University with the average the age and the body weight 19.5 years and 55.27 kg respectively. Results that were relatively accurate was found on the calcaneal loading estimation by footprint depth is presented by curve and data distribution which are in good agreement with the result of the measurement. A significant difference in estimating calcaneal loading is mainly caused by plantar foot ...

Comparison of ratio loaded and unloaded foot area of flat foot and healthy foot in younger adults

This study is aimed to investigate loaded and unloaded foot area ratio (RFA, ratio of foot area) as special tests for the basis of clinical examination of flat foot and healthy foot. Type of foot is determined by Cavanagh’s arch indexes (AI) which is the ratio between mid foot area to entire footprint area excluding the toes. Type of foot is called high arch when AI AI≥0.21 and flat foot when AI>0.26. The entire loaded foot and footprint area for evaluating AI derived from a digital footprint is modified from document scanner, while the entire unloaded foot area derived from a 3D scanner. One hundred and two healthy students (87 males and 15 females, average aged 20 years and average BMI 22.51 kg/m 2 ) is asked voluntarily for doing footprint and scan. From 102 subjects found 63 participants identified as flat foot and 31 subjects are healthy feet. This study proves that the higher the value of AI the higher the value of RFA and foot type can be predicted by the value of RFA. For type of foot is high arch RFA RFA≥0.49 and for flat foot RFA>0.55.

The effectiveness of raising the heel height of shoes to reduce heel pain in patients with calcaneal spurs

[Purpose] To investigate the effect of heel height on the distribution of plantar foot force and heel pain in patients with a heel spur. [Subjects and Methods] Plantar force was measured using 8 force sensors in 16 patients (3 men, 13 women), with symptomatic heel spur for 4 heel heights (0–4 cm). Sensors were located at the hallux (T1); medial to lateral metatarsals (M1 through M3), mid-foot (MF); and at the central, lateral, and medial heel (CH, LH, and MH). Pain was evaluated using the minimum compression force that caused pain and was measured using an algometer. [Results] Load bearing shifted from the heel (CH) to the mid-foot (MF) and hallux (T1) with increasing heel height. Raising the heel from 2 to 3 cm reduced the magnitude of load bearing, relative to the minimum compression force for pain, by 3.70% at the LH and 2.35% at the MH. Excellent clinical outcomes, defined by a 70–100% decrease in pain, were achieved in 10/16 participants with the use of a 2-cm and 3-cm heel height in men and women, respectively. [Conclusion] Increasing heel height effectively decreases the plantar force on the heel during weight-bearing activities.

DISTRIBUSI TEGANGAN PADA PERCABANGAN PIPA 90O AKIBAT TEKANAN INTERNAL MENGGUNAKAN MEH

Piping system is very important in many industries. Ones of crucial in design of piping system are todetermine the stress distribution around the branch. In this research, the distributed stress over 90o branchpiping system was evaluated with finite element method. Five models piping 90o branch which differentratio of diameter of pipe have been developed. The load applied on the models is internal pressure.The results indicate that around the branch there is stress distribution. The maximum stress is located atcenter of the branch but decrease significantly in the distance 30mm-45mm from it. Beyond the distance75mm from center, for diameter ratio 1, the model gives good agreement with experiment data