Dr. Ajay has joined the Institute of Design, Nirma University an Assistant Professor in August 2022. He is a PhD graduate from IIT Ropar in the field Computational Biomechanics and Injury Analysis. He has served IIT Delhi as Principal Scientist where he has gained experience in design of bone and implants and conducting structural analysis for simulating trauma and blast effect. He has completed BE in Production from Bharati Vidyapeeth University, Pune in 2009 and M.Tech. in Computer Aided Design and Manufacturing from NIT Hamirpur in 2013. Dr. Ajay has gained considerable experience in teaching before joining PhD. He has expertise in investigating bone adaptation mechanism, analyzing bone fracture in response to trauma, designing of bone, prosthetics, and dentures for long bone and teeth, investigating the biomechanics of tooth assembly and long bone, designing and development of military tanks and seat belt, creating and simulating real battle field environments, and computing injury
EDUCATION
B.E. (Production) Bharati Vidyapeeth University 2005-2009
M.Tech. (CAD CAM) NIT Hamirpur 2011-2013
PhD (Computational Biomechanics and Injury Analysis) IIT Ropar 2015-2021
Postdoc (Traumatic Dental Injury) IIT Delhi 2020-2022
10
Scopus Publications
152
Scholar Citations
6
Scholar h-index
5
Scholar i10-index
Scopus Publications
Biomechanical injury risk analysis of a child dummy under cricket ball impacts: A finite element study Sahana Pathak, Ajay Goyal Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine, 2025 Children, while playing cricket, may get exposed to impact-related injuries. Most available studies have been done on adult players. Pediatric biomechanics concerning cricket ball impacts have been unexamined, supported by assumptions and surrogate models. This research used a finite element model of a child dummy, a ball, and a steel chair. Four conditions based on anatomical regions: (A) Anterior precordial, (B) Subnasal, (C) Right temporal, and (D) Cranial vertex impact were simulated by impacting a cricket ball at 5, 10, or 15 m/s. Injury indicators (Cervical Spine Injury Criterion, Thoracic Compression Criteria, neck loads and bending moments, Neck Injury Criteria, head displacement, velocity and acceleration, and head injury criteria) were computed for each simulation. Von Mises stresses were computed on the skin. Computed values of indicators were compared with standard data to predict injury levels (AIS values) at different head, neck, and chest. At 15 m/s, thoracic compression attained 49.59 mm, exceeding the AIS 4 criteria for severe damage. The HIC 15 value of 297.7 at 10 m/s implies mild concussions; however, the peak head acceleration of 135.82 g signifies a considerable danger of brain injury. Subnasal impacts at 10 m/s exhibited N ij = 0.72, indicating cervical ligament tension. Research indicates elevated stress concentrations at impact locations with increased impact velocity. This study provides a comprehensive quantitative data into pediatric impact biomechanics during cricket play. This study identifies key anatomical vulnerabilities that can inform the design of improved protective gear and support the development of safer play conditions for young athletes.
Trauma-Induced Stress Distribution in Primary Incisors Restored With Preformed Zirconia Crowns: 3D Finite Element Analysis Ajay Goyal, Manjari Reshikesh, Mohammad Atif, Nitesh Tewari, Isha Duggal, Anoop Chawla, Kalpana Bansal, Morankar Rahul, Vijay Mathur, Ritu Duggal Dental Traumatology, 2025 Background/AimsPreformed zirconia crowns have emerged as the preferred choice for restoring damaged primary incisors. However, they differ from natural teeth in their biophysical properties and can potentially alter the overall response of crowned teeth to a traumatic load. This in silico study aimed to compare the response of three different traumatic loading conditions for the (i) natural (M1) and (ii) zirconia‐restored tooth models (M2) models.MethodologyA 3D dynamic finite element (FE) analysis was performed, and minimum dynamic loads required for fracture and coronal portion disjunction of both tooth models were applied in frontal, oblique, and incisal directions. Stress concentrations, von Mises stresses, fracture patterns, and displacements were compared at different periods of the loading pulse.ResultsThe computed minimum threshold loads resulting in fracture of the natural tooth model were 82 N, 166 N, and 171 N for the frontal, oblique, and incisal impacts, respectively. Fracture of the coronal portion started at 1.8 and 1.68 ms in natural tooth and zirconia‐restored tooth models, respectively. Complete disjunction of coronal and radicular portions occurred earlier in the zirconia‐restored tooth model (2.46 ms) than in the natural tooth model (4.5 ms) for frontal impact. The maximum von Mises stresses causing fracture ranged from 254 to 314 MPa for both models, following assigned element erosion criteria. The zirconia‐restored tooth model did not experience fracture during an oblique impact.ConclusionThe stress concentration patterns were seen to be altered in the zirconia‐restored tooth model. On incisal impact, the permanent tooth germ in the natural tooth model displayed stress concentrations that were not seen in the zirconia‐restored tooth model.
Enhancing Ishihara and educational images using machine learning: toward accessible learning for colorblind individuals Aahan Ritesh Prajapati, Ajay Goyal Frontiers in Artificial Intelligence, 2025 Color Vision Deficiency (CVD) affects over 300 million individuals worldwide, with protanopia and deuteranopia being the most common subtypes, causing red–green confusion. This study leverages machine learning to (a) classify reference (considered as normal vision) and simulated protanopia and deuteranopia Ishihara plate images, (b) generate corresponding enhanced versions of these images, and (c) provide improved textbook diagrams (from NCERT books) and other pseudochromatic figures for CVD students, validated through feedback from diagnosed individuals. Tritanopia and milder forms of CVD were excluded in this study. A dataset of 1,400 Ishihara plates was processed to simulate protanopia and deuteranopia perception via standard Red Green Blue (sRGB) to long-, medium-, and short-wavelength cone (LMS) modeling. Enhanced images were generated using a daltonization function defined by the error between reference and simulated images, with enhancement strength (α) optimized to maximize contrast gain while minimizing distortion. Feature embeddings from ResNet-50, EfficientNet-B0, and DenseNet-201 were fused and reduced via PCA, followed by One-vs-All (OvA) (classifiers: linear support vector machine, logistic regression, and decision tree), random forest, gradient boosting, and neural network. Results showed optimal enhancement at α = 0.54 for deuteranopia and 0.64 for protanopia, achieving contrast gains of 69.6 and 64.3, respectively, with minimal color distortion (ΔE ≈ 4.9) and negligible clipping (<0.002). The OvA strategy achieved 99.7% accuracy, while MLP reached 100% across metrics. Surveys with 15 diagnosed students confirmed substantial perceptual improvement: recognition of previously unreadable digits and symbols increased from <20% to full visibility, with mean ratings above 4/5 for enhanced images. The OvA technique integrated with daltonization can assist in enhancing Ishihara and educational images in real time.
Alternating Layers of Morselized Allograft and Injectable Ceramic Bone Graft Substitute in Acetabular Reconstruction: A Novel ‘Sandwich’ Technique Rajesh Malhotra, Deepak Gautam, Kaushik Mukherjee, Sudipto Mukherjee, Arun Manjunatha Swamy, Alok Rai, Ajay Goyal, Anoop Chawla Arthroplasty Today, 2023 Background: Impaction of morselized allograft is an appealing procedure for addressing the bone defects. However, concerns remain about its suitability for massive defects. We used a novel "sandwich" technique by impacting the morselized allograft in layers with an intervening layer of injectable bone graft substitute for restoring bone defects during acetabular reconstruction in total hip arthroplasties. Methods: From August 2015 to June 2017, 17 revisions, 4 rerevisions, and 3 complex primary total hip arthroplasties were operated by this novel technique. Postoperatively, serial X-rays were evaluated at regular intervals. Clinical and functional outcomes were assessed by the Harris hip score. To examine if introducing an injectable bone substitute into allograft stock increased its load-bearing capability, simulated mechanical testing using Synbone samples was conducted in the laboratory. Results: The mean Harris hip score significantly improved from 54.6 preoperatively to 86.8 at the latest follow-up. Graft incorporation was seen in all the cases. There was no evidence of component migration or loosening as compared to the X-rays at 3 weeks and 3 months in all the cases. With revision of component as end point, the survivorship was 100% at 82 months. The mechanical testing reported a higher capability of allograft samples when compared to those without bone substitutes. Conclusions: Our data confirms that the use of the "sandwich" technique is a reliable option for major acetabular reconstruction. Early weight bearing is a significant value addition, and short-term results confirm good clinical and functional outcome. Longer follow-up is necessary to assess the status of the construct in the long term.
Modeling cortical bone adaptation using strain gradients Abhishek Kumar Tiwari, Ajay Goyal, Jitendra Prasad Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine, 2021 Cyclic and low-magnitude loading promotes osteogenesis (i.e. new bone formation). Normal strain, strain energy density and fatigue damage accumulation are typically considered as osteogenic stimuli in computer models to predict site-specific new bone formation. These models however had limited success in explaining osteogenesis near the sites of minimal normal strain, for example, neutral axis of bending. Other stimuli such as fluid motion or strain gradient also stimulate bone formation. In silico studies modeled the new bone formation as a function of fluid motion, however, computation of fluid motion involves complex mathematical calculations. Strain gradients drive fluid flow and thus can also be established as the stimulus. Osteogenic potential of strain gradients is however not well established. The present study establishes strain gradients as osteogenic stimuli. Bending-induced strain gradients are computed at cortical bone cross-sections reported in animal loading in vivo studies. Correlation analysis between strain gradients and site of osteogenesis is analyzed. In silico model is also developed to test the osteogenic potential of strain gradients. The model closely predicts in vivo new bone distribution as a function of strain gradients. The outcome establishes strain gradient as computationally easy and robust stimuli to predict site-specific osteogenesis. The present study may be useful in the development of biomechanical approaches to mitigate bone loss.
An Invertible Mathematical Model of Cortical Bone’s Adaptation to Mechanical Loading Jitendra Prasad, Ajay Goyal Scientific Reports, 2019 Determination of mechanical loading regimen that would induce a prescribed new bone formation rate and its site-specific distribution, may be desirable to treat some orthopaedic conditions such as bone loss due to muscle disuse, e.g. because of space flight, bed-rest, osteopenia etc. Site-specific new bone formation has been determined earlier experimentally and numerically for a given loading regimen; however these models are mostly non-invertible, which means that they cannot be easily inverted to predict loading parameters for a desired new bone formation. The present work proposes an invertible model of bone remodeling, which can predict loading parameters such as peak strain, or magnitude and direction of periodic forces for a desired or prescribed site-specific mineral apposition rate (MAR), and vice versa. This fast, mathematical model has a potential to be developed into an important aid for orthopaedic surgeons for prescribing exercise or exogenous loading of bone to treat bone-loss due to muscle disuse.
Manufacturing flexibility and its effect on system performance Jordan Journal of Mechanical and Industrial Engineering, 2017
Simplified mathematical modeling of temperature rise in turning operation using MATLAB Jordan Journal of Mechanical and Industrial Engineering, 2015
A study of experimental temperature measuring techniques used in metal cutting Jordan Journal of Mechanical and Industrial Engineering, 2014
RECENT SCHOLAR PUBLICATIONS
Enhancing Ishihara and educational images using machine learning: toward accessible learning for colorblind individuals AR Prajapati, A Goyal Frontiers in Artificial Intelligence 8, 1-16 , 2025 2025
Biomechanical injury risk analysis of a child dummy under cricket ball impacts: A finite element study S Pathak, A Goyal Proceedings of the Institution of Mechanical Engineers, Part H: Journal of … , 2025 2025
Awareness and Educational Gaps in Color Vision Deficiency: A Survey-Based Analysis from Gujarat, India. F Prajapati, A Prajapati, A Goyal International Journal of High School Research 7 (8) , 2025 2025
Trauma‐Induced Stress Distribution in Primary Incisors Restored With Preformed Zirconia Crowns: 3D Finite Element Analysis A Goyal, M Reshikesh, M Atif, N Tewari, I Duggal, A Chawla, K Bansal, ... Dental Traumatology 41 (4), 445-456 , 2025 2025 Citations: 2
Data-driven crop suitability assessment using soil health index and contaminant risk index in a multi-label learning framework JP Agrawal, A Goyal Journal of Applied Horticulture 27 (4), 689-695 , 2025 2025
Alternating layers of morselized allograft and injectable ceramic bone graft substitute in acetabular reconstruction: A novel ‘Sandwich’technique R Malhotra, D Gautam, K Mukherjee, S Mukherjee, AM Swamy, A Rai, ... Arthroplasty Today 22, 101150 , 2023 2023 Citations: 4
An in silico model for woven bone adaptation to heavy loading conditions in murine tibia J Prasad, A Goyal 2022
An in silico model for woven bone adaptation to heavy loading conditions in murine tibia A Goyal, J Prasad Biomechanics and modeling in mechanobiology 21 (5), 1425-1440 , 2022 2022 Citations: 11
Modeling cortical bone adaptation using strain gradients J Prasad, AK Tiwari, A Goyal 2021
An invertible computer model for bone's adaptation to mechanical environment A Goyal 2021
Modeling cortical bone adaptation using strain gradients AK Tiwari, A Goyal, J Prasad Proceedings of the Institution of Mechanical Engineers, Part H: Journal of … , 2021 2021 Citations: 10
An invertible mathematical model of cortical bone’s adaptation to mechanical loading J Prasad, A Goyal Scientific reports 9 (1), 5890 , 2019 2019 Citations: 23
Manufacturing Flexibility and its Effect on System Performance. S Kumar, A Goyal, A Singhal Jordan Journal of Mechanical & Industrial Engineering 11 (2) , 2017 2017 Citations: 41
Simplified Mathematical Modeling of Temperature Rise in Turning Operation Using MATLAB. A Goyal, RK Sharma Jordan Journal of Mechanical & Industrial Engineering 9 (2) , 2015 2015
A Study of Experimental Temperature Measuring Techniques used in Metal Cutting. A Goyal, S Dhiman, S Kumar, R Sharma Jordan Journal of Mechanical & Industrial Engineering 8 (2) , 2014 2014 Citations: 51
Generation of Temperature Rise Distribution at Chip of EN31 Steel Due to Primary Deformation Zone during Turning Using MATLAB® and to Study its Machinability Behaviour with CVD … A Goyal International Journal of Engineering Trends and Technology 15 (3), 145-152 , 2014 2014 Citations: 1
Studying methods of estimating heat generation at three different zones in metal cutting: A review of Analytical models A Goyal, S Dhiman, RK Sharma, SK Tyagi International Journal of Engineering Trends and Technology 8 (10), 532-545 , 2014 2014 Citations: 6
Analysis of Cutting Force with Respect to Cutting Parameters when EN-38 MS is Machined with PCBN Insert A Singh, A Goyal, S Dhiman, RK Sharma, S Kumar 2013 Citations: 1
A Study of Analytical Models of Heat Generation at Three Different Zones in Metal Cutting A Goyal, S Kumar, DRS Suresh Dhiman 2013 Citations: 2
MOST CITED SCHOLAR PUBLICATIONS
A Study of Experimental Temperature Measuring Techniques used in Metal Cutting. A Goyal, S Dhiman, S Kumar, R Sharma Jordan Journal of Mechanical & Industrial Engineering 8 (2) , 2014 2014 Citations: 51
Manufacturing Flexibility and its Effect on System Performance. S Kumar, A Goyal, A Singhal Jordan Journal of Mechanical & Industrial Engineering 11 (2) , 2017 2017 Citations: 41
An invertible mathematical model of cortical bone’s adaptation to mechanical loading J Prasad, A Goyal Scientific reports 9 (1), 5890 , 2019 2019 Citations: 23
An in silico model for woven bone adaptation to heavy loading conditions in murine tibia A Goyal, J Prasad Biomechanics and modeling in mechanobiology 21 (5), 1425-1440 , 2022 2022 Citations: 11
Modeling cortical bone adaptation using strain gradients AK Tiwari, A Goyal, J Prasad Proceedings of the Institution of Mechanical Engineers, Part H: Journal of … , 2021 2021 Citations: 10
Studying methods of estimating heat generation at three different zones in metal cutting: A review of Analytical models A Goyal, S Dhiman, RK Sharma, SK Tyagi International Journal of Engineering Trends and Technology 8 (10), 532-545 , 2014 2014 Citations: 6
Alternating layers of morselized allograft and injectable ceramic bone graft substitute in acetabular reconstruction: A novel ‘Sandwich’technique R Malhotra, D Gautam, K Mukherjee, S Mukherjee, AM Swamy, A Rai, ... Arthroplasty Today 22, 101150 , 2023 2023 Citations: 4
Trauma‐Induced Stress Distribution in Primary Incisors Restored With Preformed Zirconia Crowns: 3D Finite Element Analysis A Goyal, M Reshikesh, M Atif, N Tewari, I Duggal, A Chawla, K Bansal, ... Dental Traumatology 41 (4), 445-456 , 2025 2025 Citations: 2
A Study of Analytical Models of Heat Generation at Three Different Zones in Metal Cutting A Goyal, S Kumar, DRS Suresh Dhiman 2013 Citations: 2
Generation of Temperature Rise Distribution at Chip of EN31 Steel Due to Primary Deformation Zone during Turning Using MATLAB® and to Study its Machinability Behaviour with CVD … A Goyal International Journal of Engineering Trends and Technology 15 (3), 145-152 , 2014 2014 Citations: 1
Analysis of Cutting Force with Respect to Cutting Parameters when EN-38 MS is Machined with PCBN Insert A Singh, A Goyal, S Dhiman, RK Sharma, S Kumar 2013 Citations: 1
Enhancing Ishihara and educational images using machine learning: toward accessible learning for colorblind individuals AR Prajapati, A Goyal Frontiers in Artificial Intelligence 8, 1-16 , 2025 2025
Biomechanical injury risk analysis of a child dummy under cricket ball impacts: A finite element study S Pathak, A Goyal Proceedings of the Institution of Mechanical Engineers, Part H: Journal of … , 2025 2025
Awareness and Educational Gaps in Color Vision Deficiency: A Survey-Based Analysis from Gujarat, India. F Prajapati, A Prajapati, A Goyal International Journal of High School Research 7 (8) , 2025 2025
Data-driven crop suitability assessment using soil health index and contaminant risk index in a multi-label learning framework JP Agrawal, A Goyal Journal of Applied Horticulture 27 (4), 689-695 , 2025 2025
An in silico model for woven bone adaptation to heavy loading conditions in murine tibia J Prasad, A Goyal 2022
Modeling cortical bone adaptation using strain gradients J Prasad, AK Tiwari, A Goyal 2021
An invertible computer model for bone's adaptation to mechanical environment A Goyal 2021
Simplified Mathematical Modeling of Temperature Rise in Turning Operation Using MATLAB. A Goyal, RK Sharma Jordan Journal of Mechanical & Industrial Engineering 9 (2) , 2015 2015
