A Hybrid Grey Wolf and Dipper-Throated Optimizer for
Engineering Design Optimization
Mohamed Saber 1,* Faustino D. Reyes2
1 Electronics and Communications Engineering Department, Faculty of Engineering, Delta University for Science and Technology,
Gamasa City 11152, Egypt
2 ICT Bahrain Polytechnic, PO Box 33349, Isa Town, Bahrain
Emails: Mohamed.saber@deltauniv.edu.eg ; faustino.reyes@polytechnic.bh
Received: May 27, 2026 Revised: July 11, 2026 Accepted: September 02, 2026 ⋆ Corresponding author
ABSTRACT
Optimization plays a fundamental role in engineering design, enabling cost reduction, performance enhancement,
and constraint satisfaction. Metaheuristic algorithms such as the Grey Wolf Optimizer (GWO) and Dipper-Throated
Optimizer (DTO) have been widely used for solving complex optimization problems. However, standalone algorithms
often suffer from premature convergence and limited exploration capabilities, necessitating the development of
hybrid approaches. This chapter introduces a novel hybrid algorithm, GWO+DTO, which combines the exploratory
strength of GWO with the exploitative efficiency of DTO to improve optimization performance. The effectiveness of
GWO+DTO is evaluated on two benchmark engineering problems: the Pressure Vessel Design Problem and the
Tension/Compression Spring Design Problem, comparing its results with standalone GWO and DTO. Experimental
findings demonstrate that the hybrid approach achieves superior performance, obtaining the best cost of 5950.28 in
the pressure vessel problem and 0.01266 in the spring design problem, outperforming the individual algorithms in
accuracy and efficiency. Additionally, GWO+DTO requires fewer function evaluations, highlighting its computational
efficiency. The proposed hybrid method presents a promising alternative for tackling real-world engineering
optimization challenges, with potential applications in multi-objective and large-scale optimization problems.
Keywords: Hybrid Metaheuristic Grey Wolf Optimizer (GWO) Dipper-Throated Optimizer (DTO) Engineering
Optimization Constrained Optimization
1. INTRODUCTION
Optimization is a fundamental aspect of engineering, science,
and technology, playing a crucial role in designing efficient
and cost-effective solutions across diverse fields. Many realworld
problems involve highly complex, nonlinear, multimodal,
and constrained search spaces, making it challenging
to find optimal solutions using traditional mathematical programming
techniques [1, 2]. These classical methods, such
as gradient-based and linear programming approaches, often
require well-defined objective functions, differentiability
conditions, and convexity assumptions, which limit their applicability
in solving practical engineering problems. As a
result, researchers have increasingly turned to heuristic and
metaheuristic optimization techniques, which provide robust
and flexible alternatives for handling complex and large-scale
optimization problems [3, 4].
Metaheuristic algorithms are computational methods that
imitate natural processes to iteratively refine candidate solutions
until an optimal or near-optimal solution is found.
These algorithms are designed to balance two essential aspects
of optimization: exploration (searching across diverse
regions of the solution space) and exploitation (refining
promising solutions in local neighborhoods) [5, 6]. Over