Abstract
This paper proposes a novel artificial bee colony with predation effect (ABCPE) algorithm for tuning a proportional integral derivative (PID) controller. The mathematical model of ABCPE algorithm to introduce predator effect in the foraging behavior of artificial bees colony algorithm has been formulated. The proposed algorithm has been tested on tuning problems of different process models. The simulation results reveal that the closed-loop responses are relatively fast and non-oscillatory as compared to the frequency response analysis method for reference tracking. Further, the results obtained using ABCPE are also compared with other evolutionary algorithms. The exhaustive analysis shows that the ABCPE-based solution approach leads to a set of tuning parameters having smaller overshoot, less setting time, and rise time compared to other solution approaches. The stability analysis using Nichols plot reveals that the phase margin of proposed algorithm is higher as compared to other tuning methods. Finally, the convergence behavior and robustness analysis reveals the effectiveness of the proposed approach to solve engineering design problems.
Keywords
1. Introduction
Proportional integral derivative controllers are widely accepted due to their simple structure, cost effectiveness, and optimal performance. These controllers have the advantage of lesser computational complexity and smaller hardware requirements in comparison to artificial intellect based systems which require more computational effort and memory. These advantages of PID controllers are of utmost importance, when user is opting for a real-time control solution. PID parameter tuning is a core part of the controller design. A properly tuned controller helps to achieve the desired performance of a system. Although the proportional, integral, and derivative gains are only three adjustable parameters of a PID controller, however they are difficult to be tuned properly. One of the complexity is that tedious plant tests are required to achieve controller setting for desired performance Cao (2020); O’Dwyer (2009).
The conventional approaches for tuning a PID controller include the Ziegler–Nichols (ZN) method, Cohen Coon method, and the relay auto-tuning method Bequette (2003). The other conventional methods include internal model control, direct synthesis approach, and pole placement-based methods Ogata and Yang (2002). Although these methods are easy to implement, the performance of the controller may deteriorate with changing environment/operating points Gontijo et al. (2023). In such conditions, artificial intelligence based algorithms have been explored to tune a controller Jood et al. (2019). These algorithms can be classified as artificial neural network Kumar et al. (2014), adaptive neuro-fuzzy inference system Chopra et al. (2014), and fuzzy logic Blanchett et al. (2000). These controllers give quite satisfactory performance in the presence of changing environment or model uncertainties Jood et al. (2019). However, the training of these controllers is a complex task, requires good human knowledge, as well as additional computational resources.
In recent literature, a lot of meta-heuristic techniques have been used as a solution procedure to solve the PID controller tuning problems. These methods include application of genetic algorithm Cao (2020); Pereira and Pinto (2005); Ganapathy et al. (2016), differential evolution Saad et al. (2015); Gün (2023), and particle swarm optimization Nagaraj and Murugananth (2010). Further, the other natural phenomenon based algorithms such as ant colony optimization Dhieb et al. (2019), binary-coded extremal optimization Zeng et al. (2014), chaotic PSO algorithm Pluhacek et al. (2013), artificial bee colony Martins et al. (2022), etc. have been proposed to solve engineering problems.
To obtain the controller parameters, these methods require the minimization of certain performance criteria such as integral square error (ISE) or integral of time multiplied by absolute error (ITAE). As per literature, a balanced exploration and exploitation in a swarm-based meta-heuristic algorithms is a well challenging issue Hussain et al. (2019); Singh et al. (2018a). The predator-based concepts have been introduced as a meta-heuristics to improve the performance of population-based search algorithms Silva et al. (2002). Over the past three decades, the study of behavioral interactions between predator and prey has exposed mystery of prey behavior. These studies lead to a conclusion that the predating risks influence every aspect of prey decision-making such as foraging behavior Lima (2002). In the past decade, one of the most important concepts of nature, predator-prey behavior, has been mimicked as search algorithms and presented in the literature viz. adaptive predator-prey optimization Singh et al. (2018b), integrated predator optimization Narang et al. (2012), NSGA Amiri et al. (2023), spatial predator-prey approach Laumanns et al. (1998), real coded predator-prey genetic algorithm Li (2003), synergic predator-prey optimization Singh et al. (2016), etc. These algorithms have been highly recommended as solution procedure for the diverse engineering problems.
In this paper, a novel artificial bee colony with predation effect (ABCPE) technique has been proposed, where the artificial bee colony (ABC) algorithm has been modified with predator effect. ABCPE differs itself from ABC as it emphasis on dynamic spatial structure of the bee population by considering predation effect. ABCPE introduces dynamic changes of the bee position by employing Euclidean distance based random operator to encourage self-adaptive search in the available space. The predators chase the center of bees’ swarm, thereby the bees while changing the position takes care of predation effect. This effect contributes to local optimal avoidance and strengthens global optimal solution search capability. The proposed tuning algorithm is applied to standard test systems. The main objectives of the work are outlined as follows: • Development of ABCPE algorithm, wherein artificial bee colony algorithm is modified with introduction of predator effect. • Development of solution approach, using ABCPE, for the solution of PID controller tuning. • Analyze the performance of ABCPE algorithm using simulation results of PID controller tuning problem.
The paper is organized as follows: Firstly, the PID controller problem formulation is described and the standard test system used in this research work are elaborated. Thereafter, the working principle of ABCPE algorithm is presented followed by mathematical model and algorithmic solution approach to solve PID controller tuning problem. The simulation results and observations of the proposed algorithm are presented finally, followed by the conclusions of the research work.
2. Problem formulation
Mathematically, a PID controller is represented as:
Controller tuning problem is stated as to search a suitable set of proportional, integral, and derivative gains, that is, k p , k i and k d in the available problem hyperspace such that a certain objective function is to be minimized or maximized. These objective functions are based upon error performance criteria, which reflect the expectation from the system under unity feedback condition. The performance index (PI) is calculated over t normally in the region from 0 < t < T. The performance indices used are explained as follows:
2.1. Performance index
The commonly used performance index functions are Joseph et al. (2022):
2.1.1. Integral of absolute error (IAE)
2.1.2. Integral of time absolute error (ITAE)
This performance index employs time-based scaling of error and thereby emphasizes on the error values during the latter part of the response. It ensures faster damping of oscillations and hence improves the steady state response of system.
2.1.3. Integral of square error (ISE)
2.1.4. Mean square error (MSE)
MSE reflects all variation and deviation from the target value.
In order to observe the effectiveness of the proposed solution approach to solve the problem of controller’s tuning parameters, three different types of test system are considered. These systems are 3rd order process, a ball and hoop system, and a DC motor position control system. The explanation of these systems is as follows:
2.2. Test systems
2.2.1. 3rd order system
A majority of practical systems are usually higher order systems with oscillatory transient response. Therefore, the first system considered for performance evaluation is a 3rd order system, mathematically represented as follows:
The transient response of this system is sluggish in nature Ogata and Yang (2002).
2.2.2. Ball and hoop system
The ball and hoop system is a bench mark control problem and its transient response exhibits a complex dynamics which is modeled as a fourth order system. The transfer function of system is represented by equation (7) as below:
2.2.3. DC motor position control system
The transfer function of DC motor position control system is given by following equation:
3. Artificial bee colony with predator effect algorithm
Artificial bees colony with predator effect (ABCPE) algorithm mimics the idea of honeybee swarm’s collective intelligence for foraging activity. ABCPE owes employed bees to search for food source, onlooker bees for selection of the best quality food source, and the scout bees identify new food source Karaboga and Basturk (2007). The food source position in the feasible search domain represents the possible solution of the problem, whose quality is indicated by the nectar amount. The predation psychological feature imposes an extremely high fitness cost Bednekoff (2007). Hence, selection process has to prefer foraging activity such that forage gains balance-out the predation risk Brown et al. (1999). The predator-prey foraging game analysis indicates that the predator opt prey hunting in the high quality areas Hugie and Dill (1994). Therefore, the prey has to negotiate between forage advantage and predation risk Sih (1998).
In ABCPE, the employer bees and onlooker bees visit the most promising locations to maximize their foraging success. As the predators opt high quality foraging arena for prey bee, the bees often prefer to visit less rewarding locations to trade-off foraging benefits and predation risk Jones and Dornhaus (2011). An experimental study on the bumble bees’ foraging behavior, associated with predation risk, shows that the bees experiencing a simulated attack on a most rewarded foraging locations were more likely to visit little degraded arena on consequent forage trips. The predator effect has been successfully mathematically modeled and analyzed for multi-behavioral strategies Mitchell (2009), swarm-based optimization Silva et al. (2002) and behavioral strategies in predators and prey Haynes and Sen (1995). Silva et al. (2002) suggested a predator’s mathematical model, wherein Px
j
represents the predator’s position in the jth dimension of N
D
dimensional search space, is randomly initialized as follows:
The predator’s physiology is to visit high rewarded areas identified and this behavior is reflected by a mathematical expression as:
The ABC algorithm mimics the honey bee activity specific to the foraging interests only represented by mathematical equation (11). More detail of ABC algorithm is presented in Appendix A. The updated position of ith honey bee among population of N
P
honey bees has been represented by xb
ij
. It is related to present position x
ij
as follows:
In the proposed ABCPE, in order to trade-off the foraging gains and predation risk, the employer bees and onlooker bees have been modeled to change their foraging preferences in the presence of predators, as the predators are attracted towards high quality foraging arena to locate prey bee. Therefore, the mathematical equation to represent new bee position xp
ij
has been updated considering predation effect as follows:
The bees maximize their foraging success by visiting the safer foraging locations. A greedy search-based decision approach has been applied to replace the foraging position vector
The process explained above has been employed in both employer bee phase and onlooker bee phase, as shown in Algorithm 1 pseudo code. The ABCPE solution approach starts with a uniformly distributed, randomly generated population of bees and a predator, both having N D dimension. The population size has been represented by N P . The iterative process to improve the quality of solutions, indicated by a maximization process using objective function equations (2)–(5), proceeds until termination criteria has been satisfied. The ABCPE algorithm to solve problem in-hand is as follows:
4. Results and discussions
The artificial bee colony with predator effect algorithm based solution approach to solve the PID controller design problem has been explained in the previous section. The solution approach described in pseudo code has been implemented in MatLab 2019, i5 processor 8 GB RAM. The solution approach has been applied to solve test systems namely 3 rd order system, ball and hoop system and DC motor position control system considering the performance index listed by equations (2)–(5), respectively. The boundary range for decision variables is [0, 20]. In order to obtain the solution of problem, the population size N B has been fixed at 10. The number of iterations considered are 200. The detailed discussion of key observations related to solution obtained for three different systems has been presented. The observations are depicted using a comparison of tuning parameters, graphical representation of transient response, examination of transient behavior specifications, stability analysis and convergence behavior in the following section.
4.1. 3rd order system
Comparison of controller parameters of 3 rd order system.
The transient response for all the performance indices corresponding to tuning parameters obtained using ABCPE algorithm listed in Table 1, has been graphically depicted in Figure 1. For the comparison purpose a standard method namely frequency response analysis approach for reference tracking has been applied using PID tuner application tool available in Matlab 2019. The comparison of transient response plots show that the parameters obtained by ABCPE algorithm offers advantage of less oscillatory and faster response with smaller steady state error. Transient response of 3rd order system.
Comparison of transient response specifications of 3rd order system.
The stability analysis of 3rd order system along with the proposed ABCPE control method and with existing methods has been carried out here in this section. The Nicholas stability plot of the given system with various controllers is shown in Figure 2. To obtain the stability plot of the system, the open loop transfer function given in equation (6) and the tuned parameter values of PID controller given in Table 1 have been used. In the case of DE-CHAOS and SOMA, the system is showing a phase margin (PM) of 30.8° and 79.5°, respectively. However, in the case of proposed ABCPE method, the PM has been improved considerably to a value of 84.4°. Stability plot of 3rd order system.
Comparison of controller parameters of ball and hoop system.
Ball and Hoop System.
The transient response for all the performance indices’ corresponding to tuning parameters obtained using ABCPE algorithm, listed Table 3, has been graphical depicted in Figure 3. The comparison of transient response plots show that the parameters obtained by ABCPE algorithm offers advantage of smaller overshoots and acceptable transient behavior specifications. Transient response of ball and hoop system.
Comparison of transient response specifications of ball and hoop System.

Stability plot of ball and hoop system.
4.2. DC motor position control system
Comparison of controller parameters of DC motor position control system.
Figure 5 graphically depicts the transient response for all the performance indices corresponding to tuning parameters obtained using ABCPE algorithm, listed in Table 5. The comparison of transient response plots show that the parameters obtained by ABCPE algorithm offers advantage of negligible overshoots as shown in Table 6. Transient response of DC motor position control system. Comparison of transient response specifications of DC motor position control system.
The Nicholas chart for stability analysis is plotted in Figure 6. In the case of DE-CHAOS and SOMA, the overall system shows the PM of 70.2° and 74.6°, respectively, while with ABCPE PM is 86.2° which proves the dominance of ABCPE control method. Stability plot of DC motor position control system.
4.3. Convergence behavior and robustness analysis
The convergence behavior analysis of the proposed ABCPE algorithm for different objective functions is presented from Figures 7–10, for all the three test systems. It has been observed from the convergence plots that ABCPE swiftly moves toward the optimal solutions at a uniform pace under the influence of predator effect. Convergence plot of ABCPE for IAE performance index. Convergence plot of ABCPE for ISE performance index. Convergence plot of ABCPE for ITAE performance index. Convergence plot of ABCPE for MSE performance index.



Statistical observations of 3rd order system.
Statistical observations of ball and hoop system.
Statistical observations of DC motor system.
Convergence behaviour of ABCPE for various performance index.
5. Conclusion
An ABCPE algorithm has been proposed to design PID controller to improve the transient and steady state response of the systems. The performance of the proposed solution approach has been verified using three different test problems namely, 3 rd order system, ball and hoop system and DC motor position control system. The error based performance index such as IAE, ISE, IATE and MSE have been used in the ABCPE algorithm’s performance analysis. The controller designed using proposed method has been compared with the other design methods presented in the literature. The experimental simulations confirm that the ABCPE-based solution approach has been able to search control parameters smaller in magnitude thereby facilitating controller's practical implementation possible. The transient behavior comparison shows the supremacy of ABCPE over other methods. The ABCPE approach has successfully determined the tuning parameters that results in smaller overshoots, lesser rise time and settling time for all the considered test systems. The stability analysis of the proposed algorithm has been carried out using the Nicholas plot which reveals an improvement in the PM of systems under consideration using the proposed ABCPE algorithm. It clearly shows the improved PM of the systems under consideration when the proposed ABCPE has been applied. The exhaustive analysis shows that the ABCPE has the ability to obtain feasible solutions with lesser computational efforts, which is a desirable feature for online tuning of controllers. Finally, the convergence behavior and robustness analysis proves the effectiveness of proposed solution approach to solve the controller design problem.
Footnotes
Author contributions
The first author has specialization in the field of hybrid optimization algorithms and he has contributed for the development of ABCPE algorithm. The second author has expertise in the field of control engineering and they are responsible for PID controller tuning part. The last author has contributed in the compilation of the manuscript.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Ethical statement
Appendix
