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Computational fabrication relies on time-synchronized operation of various machine components. Designing machines for novel workflows is of interest to the computational fabrication community, but designing control systems for these machines, especially with diverse actuators and sensors, remains challenging. We present MAXL, a modular, extensible machine control architecture that enables synchronous control of heterogeneous components. We contribute (1) a design pattern for a distributed trajectory object with one author and multiple readers, (2) high- and low-level APIs for interfacing this trajectory object to modular hardware and to digital fab applications (3) a simple time-synchronization algorithm and queuing scheme for distributing the trajectory object, and (4) an extensible hardware implementation of MAXL. We demonstrate MAXL’s utility in developing new computational fabrication applications by integrating it into two motion control applications; one for time-synchronized data output (light-painting), and the other for time-synchronized data retrieval (from an accelerometer). Finally, we discuss how MAXL can be extended for use in future machine applications.

Objectives The exertion of self-control has been associated with impaired performance on subsequent physical tasks also requiring self-control. However, the effect in well-trained individuals, and of nutritional intervention strategies to reduce the impact of self-control exertion are unknown. This study, therefore, explored the effect of self-control exertion on endurance performance, and pacing strategies, in well-trained individuals. A further aim was to examine the potential for a caffeine mouth rinse to attenuate any decrements in performance due to self-control exertion. Method Following familiarization, fifteen trained male cyclists completed four simulated 10 km cycling time-trials on a cycle ergometer. Prior to each time-trial, participants completed a congruent Stroop task, or an incongruent Stroop task, to manipulate self-control. They also received either a caffeine (containing 40 mg of dissolved caffeine) or placebo mouth-rinse prior to, and every 2 km during, the cycling time-trial. The participants' performance time, subjective measures (perceived pain, motivation, task importance, and RPE), heart rate, and blood lactate concentration were recorded throughout the time-trials. Data were analysed using three-way (self-control*caffeine*split time) repeated measures ANOVA. Results There was no effect of self-control or caffeine on overall 10 km performance time (all p > 0.05). However, following self-control exertion, split time was significantly slower at 3 km (p = 0.031) and 5 km (p = 0.034), and tended to be slower at 1 km (p = 0.088) and 7 km (p = 0.078). There was no effect of the caffeine mouth rinse, nor did this interact with self-control, to affect split times (all p > 0.05). Prior self-control exertion and a caffeine mouth rinse did not influence perceptions of pain, motivation, and task importance in well-trained individuals (all p > 0.05). Conclusions Findings suggest that prior self-control exertion affects self-regulatory pacing strategies d