Our tutor gave us an OSBM and we'd to determine a TBM on site by following a group of 'flying levels'. The equipment I used was a dumpy level, a tripod stand and a staff. We started out by setting up our equipment up, we'd to make certain the stand was at an appropriate height that suited you and that the dumpy level was made level by adjusting it therefore the bubble was in the centre. Someone then stood at the idea with the personnel which we were asked to evaluate, in our circumstance it was the drains. We made take note of of the measurement then moved the individual with the personnel moved to another point. We then were required to modify the dumpy level to make it level again before we had taken another dimension. We retained the dumpy level in the same place before staff got so far away that when we searched through the dumpy level it looked over the staff. That is when we moved the dumpy level; this would be our first change point. It continued until we reached the TBM.
My Collimation method looks like;
When our group completed a linear study surrounding a parcel we first create our ranging poles, these are cylinder formed timber poles which are usually 2. 5mm long. We then used a fibreglass tape to measure the distance of every thing from each pole. The precision of some measurements may be affected by a range of different reasons, for example;
Errors can also appear whilst scheduling and measuring. Types of some mistakes could be, miscounting, misreading and saving the wrong dimension. If these flaws do not get noticed early enough then your survey will have to be redone. The ultimate way to avoid these errors is to double check that what you have written is the same as the measurement you have just read. However, not absolutely all errors are right down to the person executing the review. Some errors may occur scheduled to poor equipment. For instance, utilizing a tape that has widened due to exposure to a high temperature or a tape that has been permanently extended whilst trying to prevent it from sagging. You are able to prevent this by assessing the tape to a typical metallic tape. Some errors that are small. The surveyor could be brief sighted therefore his readings are damaged. The only way to beat this error is perfect for the surveyor to repeatedly check their readings.