After we know the theory of the motors inside the drill and also understand how the input energy producing the output power, modifications and improvements will be part of our interest as well. In this part, we will separate into 2 sections where the 1st section will be the improvements and modifications had done onto the surgical drill. The 2nd section will be about the future improvements and modifications that can be done on the surgical drill.By looking back the history or timeline of surgery drilling, although there is no strong evidence, but seems like the first drilling surgery is known as trepanning. Trepanning also known as trephination and trephining, in other words, making a burr hole. This hole is drilled or scraped into the human skull. As dura mater is being exposed, treatment of disease related to intracranial disease can be proceeding. The oldest evidence will be the 120 prehistoric skulls found at burial site in France date to 6500 BC. By looking at this evidence, we can say that driller is exists since or before 6500 BC.As time passes, surgical drill encounters a big change where modifications and improvement is being made on it to fulfill the need of the surgeon. There are some drastic changes in surgical drill. The first one will be drill had evolutes from mechanical power to current energy powered and further to battery powered in this 21st era. Without any doubt, the surgical drill had become cordless and its battery is rechargeable. Not only that, the surgical drill also can be powered by battery and also alternating current from the plug to prevent the condition where the battery is run off. For commercialize purposes, extra battery pack is also available for emergency used. Besides that, as time passes, various types of drill bits are invented for different use. As for convenient, innovator invented surgical power tool where drill bits can be change and make it a multi functional surgical tools. Nowadays, there are also disposable drill bits (one time use) beside than the reusable drill bits to ease the problems of sterilization. The dimension and weight of the surgical driller is change from heavy, big and bulky to lightweight, small and easy handling. This not only eases the storage purposes but also improved in handling and maneuver characteristics. The handgrip of the driller also being improved as to prevent slip is happening. As the surgical drill is being used in different part of the body, different speed is required and thus the surgical drill had an option where the speed is adjustable to certain revolution per minute (rpm) based on the torque power needed. There are some drawbacks occurred in this surgical drill, but they are accompanied by solutions. The first draw back will be the long vibration will caused fretting corrosion. As to prevent it, connection between the battery pact and the electronic circuit is needed. Thermal injury or thermal necrosis to the bone surrounding is another drawback of the surgical drill. This can be solved by improving the drill bits design. Last but not least, a significant improvement will be the present of safety lock on the drill bits to prevent it from misplaced and dropped out during the drilling process.Above is the advancement of the surgical drill from long time ago until today. But this doesnt mean the stop of the improvements and modifications. There are some modifications we can do on current surgical drills. As for the battery powered surgical drill, there will be a phenomena where the battery pack tends to slip out as during drilling process due to the vibrations and gravitational effect. This can be improved by modified the design such as adding a locking switch between the battery pack and the surgical driller. Although lightweight surgical drill is what we needed, but different people especially surgeon will have different requirement in weight of the driller. Heavy driller might be more suitable for certain surgeon in handling a surgical driller. Therefore, we can actually adopted the special features of gaming mouse where the weight of the mouse can be adjust by adding or removing weights in the custom weight system. Apart from that, we also can replace the drill alignment devices by having laser pointer on the surgical drill. This can ease the procedure of surgery as well as increase the accuracy and precision of the drilling point. Just like other machines, surgical driller also face problem of overheating. We can maintain the temperature of the surgical driller at the normal optimum functional range of temperature by having heat remover or just by improve the design. Besides, we also can improve the surgical driller by having alarm system. This alarm system will warn the surgeon if the drill bits is not inserted correctly or wrong speed and power is chosen for that particular types of drill bits. Wrong speed of the surgical driller used on patients might cause extra unwanted avoidable damage to the patients.Advancement and improvements of surgical driller will be needed for future and it is important for us to have more features on the surgical drill which helps us in medical field.